3I/ATLAS is only the third object known to have entered our solar system from another planetary system — after the cigar-shaped space-rock 'Oumuamua, discovered passing through the solar system in Oct. 2017, and the first interstellar comet 2I/Borisov, spotted in our stellar backyard in August 2019. The brief presence of these bodies in the solar system offers a unique glimpse into the chemical makeup around other stars.

Scientists had expected 3I/ATLAS to brighten as it made its closest approach to the sun, or reached perihelion, on Wednesday (Oct. 29). After all, this is a phenomenon common to comets originating from the shell of icy bodies at the edge of the solar system called the Oort Cloud. It happens because radiation from the sun causes solid ice to transform straight into gas, a process called sublimation. This gas then erupts from the shell of the comet, casting off solid dust and growing the halo around a comet, the coma, and its characteristic cometary tail. The dust reflects light, thus boosting the brightness of the comet. 3I/ATLAS, however, brightened way faster than anticipated.

"The reason for 3I’s rapid brightening, which far exceeds the brightening rate of most Oort cloud comets at similar r [radial distance], remains unclear," the scientists behind the research, Qicheng Zhang of Lowell Observatory in Flagstaff, Arizona, and Karl Battams, an astrophysicist at the Naval Research Laboratory (NRL) in Washington DC, write in a paper discussing the observation published on the research repository site arXiv.

The rapid brightening of 3I/ATLAS was observed by STEREO-A and STEREO-B, the twin spacecraft that make up Solar Terrestrial Relations Observatory (STEREO), by the sun observing Solar and Heliospheric Observatory (SOHO), and the weather satellite GOES-19. The space-based observations were necessary because ground-based instruments won't be able to observe the interstellar comet again until it passes out from the other side of the sun into its "postperihelion" phase, escaping the glare of starlight in mid- to late-November 2025.

The team proposes a few different mechanisms that could account for the unexpectedly rapid brightening of this comet from beyond the solar system. It could be the result of the speed at which 3I/ATLAS is approaching the sun; alternatively, it could tell scientists something about the comet itself. That is exciting because if the internal composition of 3I/ATLAS is different from that of the nuclei of Oort cloud comets, it could mean that the planetary system from which it originates also has a different chemical makeup.

"Oddities in nucleus properties like composition, shape, or structure — which might have been acquired from its host system or over its long interstellar journey — may likewise contribute [to the rapid brightening]," Zhan and Battams continued. "Without an established physical explanation, the outlook for 3I's postperihelion behavior remains uncertain, and a plateau in brightness — or even a brief continuation of its preperihelion brightening — appears as plausible as rapid fading past perihelion."

The authors also suggest that sublimation could be occurring differently than expected for 3I/ATLAS because the interstellar comet was still dominated by the sublimation of carbon dioxide at an unusually close distance from the sun, around three times the distance between Earth and our star. This may have resulted in cooling that had until now suppressed the sublimation of water ice to steam.

Clearly, 3I/ATLAS continues to baffle and intrigue scientists in equal measure, and it is a fairly certain bet that once it escapes the glare of the sun, we will discover even more curiosities surrounding this interstellar intruder.

"Continued observations may help provide a more definitive explanation for the comet's behavior," the duo of scientists concluded.

A paper about these results can be viewed on the pre-print repository arxiv.

Satellite footage caught the hurricane in rotation on Tuesday (Oct. 28) as it wreaked destruction across the Caribbean. Imagery from the GOES-19 satellite shows "mesovortices" surrounding the hole, according to the National Oceanic and Atmospheric Administration (NOAA).

Metavortices refer to "small-scale rotational features" around the eye of the storm; they form in circumstances of "extreme differences in wind speed and direction," Weather.com states.

Emergency authorities told the Associated Press that Melissa is one of the most powerful Atlantic Ocean hurricanes ever recorded. Human-driven climate change has caused an overall intensification of extreme weather, including hurricanes.

Melissa hit Jamaica on Oct. 28 as a Category 5 storm (the strongest type of storm) with winds of 185 miles per hour (295 kilometers per hour).

Desmond McKenzie, deputy chair of Jamaica's disaster risk management council, declined to share how many people have died, although authorities separately told AP at least four deaths occurred in southwest Jamaica. Roughly 72% of the island has no power and 65% of mobile phone sites are down.

In Haiti, AP added, at least 25 people were killed and 18 others missing following flooding. Cuba had no reported deaths after Melissa hit as a Category 3 on Wednesday (Oct. 29), but "many communities were still without electricity, Internet and telephone service because of downed transformers and power lines," AP stated.

As of Thursday (Oct. 30) morning, Melissa was classified as a Category 2 storm with top sustained winds nearing 105 mph (169 kph) and is situated roughly 515 miles (830 kilometers) southwest of Bermuda, which remains under hurricane warning at the time of AP's report.

Built from data collected by the Murchison Widefield Array (MWA) telescope in Western Australia, the image combines observations from two massive surveys — known as GaLactic and Extragalactic All-sky MWA (GLEAM) and GLEAM-X (GLEAM eXtended) — to produce a portrait that is twice as sharp, 10 times more sensitive and twice as wide as its predecessor released in 2019, according to a statement from the International Centre of Radio Astronomy Research (ICRAR).

"This vibrant image delivers an unparalleled perspective of our galaxy at low radio frequencies," Silvia Mantovanini, a PhD student from ICRAR’s Curtin University team and lead author of the study, said in the statement. "It provides valuable insights into the evolution of stars, including their formation in various regions of the galaxy, how they interact with other celestial objects and ultimately their demise."

Over 18 months, the team used about one million computing hours at the Pawsey Supercomputing Research Centre in Australia to process and merge data from the two surveys into the final image, cataloging nearly 100,000 radio sources.

The map — a full, zoomable version of which you can find here — captures a wide range of radio wavelengths, or "colors" of radio light across the Southern Galactic Plane, offering an unprecedented look at the Milky Way's hidden structure. By observing the galaxy in low-frequency radio light, astronomers can peer through the dense clouds of dust and gas that block visible wavelengths, exposing supernova remnants — the immense, expanding shells of gas and radiation that mark the explosive death of a star — and regions of ionized gas where new ones are being born.

"You can clearly identify remnants of exploded stars, represented by large red circles," Mantovanini said in the statement. "The smaller blue regions indicate stellar nurseries where new stars are actively forming."

This expansive view of the Milky Way may also shed new light on pulsars — rapidly spinning neutron stars whose powerful radio pulses and unpredictable behavior remain a mystery, the researchers said.

The newly released image is fully interactive. Viewers can pan across the bright horizontal band charting the star-packed Southern Galactic Plane and zoom in on the Milky Way’s turbulent stellar activity, glowing nebulae, compact pulsars and even distant background galaxies beyond our own.

"This low-frequency image allows us to unveil large astrophysical structures in our galaxy that are difficult to image at higher frequencies," Natasha Hurley-Walker, associate professor at Curtin University and co-author of the study, said in the statement. "No low-frequency radio image of the entire Southern Galactic Plane has been published before, making this an exciting milestone in astronomy."

This map sets the stage for the Square Kilometre Array Observatory’s SKA‑Low telescope — the world’s largest low-frequency radio array — which, after it's completed within the next decade, will probe the Milky Way and beyond with unprecedented sensitivity and detail.

Their findings were published Oct. 28 in the Publications of the Astronomical Society of Australia.

What is it?

Founded in 1964, the Kitt Peak site was chosen by the National Science Foundation to house a national observatory capable of delivering clear, dark-skied views of the cosmos. There, more than two dozen optical and radio telescopes now share the peak with ancient desert winds and perhaps, in the spirit of Halloween, a few ghost stories yet untold.

Over the decades, the observatories on Kitt Peak have helped map dark matter, chart distant galaxies and train generations of astronomers.

Where is it?

Kitt Peak is in the Baboquivari Mountains of southern Arizona, 56 miles (90 kilometers) southwest of Tucson on land owned by the Tohono O'odham Nation. The telescope complex sits at an elevation of about 7,000 feet (2,100 meters).

Why is it amazing?

The vivid orange sky at Kitt Peak National Observatory is more than just a Halloween color; it shows the dry air and lack of light pollution at the site, two things needed for pristine astronomy. As even the tiniest speck of dust, or nearby city lights can break equipment or make noise in readings, remote areas like Kitt Peak offer sanctuary to astronomers peering deep into space.

Want to learn more?

You can learn more about ground-based telescopes and observatories.

The supernova at the heart of this research, designated SN 2024bch, erupted around 65 million light-years away from Earth and was first observed in February 2024. It is an example of a Type II supernova, an explosion that occurs when nuclear fusion ceases in the solid iron core of a massive star, causing it to collapse, sending shockwaves into the star's outer layers, leading to them being ejected.

Scientists have always assumed that when this stellar ejecta violently slams into dense gas surrounding the dying star, known as the circumstellar medium, this generates narrow emission lines in the light or spectra seen from Type II supernovas. However, SN 2024bch seems to be "anti-social", in that its ejected matter seems to not interact violently with a surrounding gas shell. However, these narrow lines are still apparent in its spectra.

The team behind this research, hailing from the National Institute for Astrophysics (INAF), studied this supernova for 140 days, using a range of ground-based telescopes and the Swift spacecraft, discovering the narrow emission lines in its spectra. This feature has previously been considered a test for discovering if a dying star is interacting with its environment.

However, in the case of SN 2024bch, the released energy doesn't seem to be the result of ejected matter mixing with a dense gas shell. Instead, the INAF researchers suggest a different mechanism to account for the energy, termed Bowen fluorescence.

"We applied a non-traditional and unprejudiced perspective," Leonardo Tartaglia, team leader and INAF researcher, said in a translated statement." For the first time in this type of transient, we demonstrate that the primary mechanism is Bowen fluorescence, a phenomenon known since the first half of the 20th century that had never been considered in the study of similar objects. Our scenario describes all the evolutionary phases of the supernova with great precision."

Bowen fluorescence is akin to an echo but of high-energy light rather than sound. In this case, intense ultraviolet light from the supernova excites surrounding helium atoms, and these atoms then transfer energy to other elements like oxygen and nitrogen also present around the dying star. It is this transfer of energy that generates the narrow spectral lines seen by the team.

This revelation means scientists might have to rethink Type II supernova models, which would result in some of these cosmic explosions being ruled out as a source of neutrinos, virtually massless, chargeless "ghost particles" that stream through space at near light-speed.

This could have ramifications for a powerful method of investigating the cosmos called multimessenger astronomy, which involves studying events and objects in electromagnetic radiation along with gravitational waves or neutrinos.

"Our study highlights that, for at least a fraction of these transients, interaction is not the primary driver of emissions, and this has important implications for multi-messenger astronomy," Tartaglia said. "Showing no evidence of interaction, supernova SN 2024bch lacks the physical conditions necessary for the emission of high-energy neutrinos."

The team's research has been accepted for publication in Astronomy & Astrophysics.

They're spooky tricksters in their names, as they have nothing to do with planets at all and are rather the gory scenes of stars dying. The term "planetary nebula" actually comes from an accident. Long ago, astronomers using early-iteration telescopes thought these objects looked like planets because of how rounded they appeared. We now know this to be untrue, of course, but the planetary nebulas continue to be disguised by their own titles.

But once you've moved on from this trick, the ruse is softened by the absolute treat it is to view one of these enchanting bundles of gas and dust. Indeed, the planetary nebula seen above, known as the Red Spider Nebula and imaged by the James Webb Space Telescope (JWST), is a terrific example of the rich scientific detail and aesthetic beauty these objects can offer.

To be clear, this image isn't exactly accurate in its color, because the JWST doesn't capture images like a normal camera. Rather, it collects infrared light emitted by different parts of objects (light that's invisible to us), then sends that information back to scientists. Astronomers can put together a picture using that data, then color it artificially to make various sections stand out.

What you're looking at here is the aftermath of a sun-like star that eventually reached the end of its life and poofed out into a cool red giant star. This will happen to our sun one day as well: It will bubble out to over 200 times its regular size and destroy everything in its path, including (perhaps) Earth.

Eventually, the outer layers of such a red giant begin to shed off until the raw core of the star is revealed. As a result, you get something like what we see in the image here.

To break the Red Spider Nebula down a little bit, at the very center is a single star that you can see, but the European Space Agency explains in a statement that there is likely also a second companion star that we just can't make out in this particular view. The reasoning there is that the specific shape of this nebula, aka its hourglass look, indicates a possible double star situation. The JWST's infrared capabilities also show a "shroud of hot dust" surrounding the visible star, ESA explains.

The lobes of the Red Spider Nebula are three light-years long each, inflated by gas from the central star shooting outward for thousands of years. The S-shape you can make out if you go from the northeast to the southwest part of the reddish area within the nebula comes from light emitted by ionized iron atoms, which refers to iron that has either gained or lost a quantity of its electrons. In fact, on that note, the blue lobes we see are representative of H2 molecules (involving two hydrogen atoms) emitting light.

Yet one of the most striking aspects of this scene comes not from the nebula itself but rather from the spectacular backdrop of stars behind it. Back when the JWST's first images were released, scientists were overjoyed to see how much detail the observatory picks up when peering into the universe, whether or not it was requested to collect that detail. That quirk of the JWST never faded, as the telescope naturally cocoons its targets in only the most deserving frames.

The twinkliest of the stars in this frame also have eight points if you look closely (two of the points are horizontal through the center and shorter than the other six), characteristic of a JWST image due to the way the telescope's hexagonal mirror works.

An iconic signature like that may make it difficult for the JWST to give us a trick like the planetary nebula crew, but at least it nails the treats.

What is it?

The Copernicus program is an initiative by the European Union to monitor Earth. It comprises several families of "Sentinel" satellites, each operated by the European Space Agency and tasked with different sensing capabilities: land, ocean and atmosphere.

Because the data is freely available to researchers under the Copernicus program, scientists can support disaster management, build better early warning systems, and have better insights into how global warming and climate change are affecting hurricanes.

Where is it?

Hurricane Melissa made landfall in Jamaica on Oct. 28, 2025.

Why is it amazing?

Hurricane Melissa underwent a period of rapid intensification, becoming one of the most powerful storms in the Atlantic in 2025. When it made landfall in Jamaica on Oct. 28, 2025, it was the most powerful storm in the country's history. Monitoring how storms change is crucial because intensification rates are hard to predict, and stronger storms mean higher risk of catastrophic damage.

Understanding and analyzing the processes behind hurricane intensification, via the use of satellites like Sentinel-2, can help to improve hurricane forecasting and, in the process, save lives.

Want to learn more?

You can learn more about Earth-monitoring satellites and the European Space Agency.

Using the James Webb Space Telescope, researchers applied a new technique called 3D eclipse mapping, or spectroscopic eclipse mapping, to track subtle changes in various light wavelengths as WASP-18b moved behind its star. These variations allowed scientists to reconstruct temperature across latitudes, longitudes and altitudes, revealing distinct temperature zones throughout the planet's atmosphere.

"If you build a map at a wavelength that water absorbs, you'll see the water deck in the atmosphere, whereas a wavelength that water does not absorb will probe deeper," Ryan Challener, a postdoctoral associate in Cornell’s Department of Astronomy and lead author of a study published on the research, said in a statement. "If you put those together, you can get a 3D map of the temperatures in this atmosphere."

WASP-18b is located about 400 light-years from Earth; it has roughly 10 times Jupiter's mass and completes an orbit of its host star in just 23 hours. Because it's so close to its star, temperatures in the planet's atmosphere reach nearly 5,000 degrees Fahrenheit (2,760 degrees Celsius). Those scorching conditions made it an ideal candidate for testing the new method of 3D temperature mapping.

The map revealed a bright central hotspot surrounded by a cooler ring on the planet's dayside — it has a tidally locked orbit, meaning that one side of the planet is always facing its star — demonstrating that the exoplanet's winds fail to distribute heat evenly across the atmosphere.

Remarkably, the hotspot showed lower water vapor levels than WASP-18b's atmospheric average. "We think that's evidence that the planet is so hot in this region that it's starting to break down the water," Challener said. "That had been predicted by theory, but it’s really exciting to actually see this with real observations."

This new 3D eclipse mapping technique will open many doors in exoplanet observations, as it "allows us to image exoplanets that we can't see directly, because their host stars are too bright," said Challener. As 3D eclipse mapping is applied to other exoplanets observed by Webb, "[w]e can start to understand exoplanets in 3D as a population, which is very exciting," he added.

The team's research was published in the journal Nature Astronomy on October 28, 2025.

Perihelion for 3I/ATLAS takes place on Oct. 30, when the interstellar interloper will be 1.35 astronomical units (125 million miles, or 202 million kilometers) from the sun. (One astronomical unit is the average Earth-sun distance — about 93 million miles, or 150 million km.)

Perihelion is the point in an object's orbit where it is closest to the sun. For comets on highly eccentric orbits, as opposed to planets on near-circular orbits, the effect of perihelion can be dramatic. As a comet nears the sun, the growing warmth causes ices on its surface to sublimate and it begins outgassing, growing a cloud called a coma around its nucleus. Comets voyaging near the sun also commonly sprout two tails — a dust tail and an ion tail made of charged particles stripped away from the comet by the solar wind. This activity makes the comet brighter and hence more noticeable, and at perihelion this outgassing, in theory, is at its most active.

As an interstellar object that is just passing through our solar system, 3I/ATLAS is not orbiting the sun. Nevertheless, its trajectory brings it closer to the sun and then farther away again, meaning it also has a perihelion approach.

Unfortunately, 3I/ATLAS moved into solar conjunction at the end of September. When this happened, it became lost in the sun's glare as it moved around the back of the sun, out of sight from Earth. It will not reappear in Earth's morning sky until later in November or the beginning of December, meaning that telescopes on Earth and in Earth orbit or at the L2 Lagrange point — a gravitationally stable spot on the other side of our planet from the sun — will miss out on seeing 3I/ATLAS at perihelion.

All is not lost, however, as we have a flotilla of spacecraft exploring the solar system that will have much better viewing angles than we get here on Earth. The small armada of spacecraft at Mars, for example, have a view of the hemisphere of the sun that 3I/ATLAS is currently rounding. In fact, our Mars missions had a ringside seat to 3I/ATLAS' closest approach to the Red Planet on Oct. 3, when it was 0.19 AU (17.6 million miles, or 28.4 million km) distant.

Other spacecraft that will be able to watch 3I/ATLAS at perihelion include NASA's Psyche mission to the asteroid of the same name and the Lucy mission to Jupiter's Trojan asteroids. Meanwhile, the European Space Agency's Jupiter Icy moons Explorer (JUICE) probe, which recently conducted a flyby of Venus on its elongated journey to the Jovian system, will be closest as it heads in the general direction toward 3I/ATLAS. Unfortunately, because JUICE is currently using its primary antenna as a sun-shield to protect its instruments, it won't be able to transmit the data from its observations of 3I/ATLAS back to Earth until next February.

Scientists are most interested in studying the chemistry of the comet at perihelion, because the gases and dust that come off the comet reveal its composition. Astronomers have already found that 3I/ATLAS contains more carbon dioxide than ordinary comets in the solar system, and a higher abundance of nickel. These differences reveal the chemistry of the molecular cloud of gas that spawned the comet and its home star system over seven billion years ago, allowing astronomers to make direct comparisons between the chemistry of the solar system and of the original home of 3I/ATLAS. At perihelion, more molecules could be revealed: So far, there has been a dearth of iron, but will iron emission from the comet pick up at perihelion?

When 3I/ATLAS does re-emerge from the sun at the back end of November, it could still be quite active — comets are unpredictable at the best of times — but, given its distance from Earth, it is expected to be quite faint, at a predicted magnitude 12. Astro-imagers and users of smart telescopes will be able to capture it, and it will of course be easy prey for the likes of the Hubble and James Webb space telescopes.

Segue 1 is an ultra-faint dwarf galaxy located about 75,000 light-years from Earth, making it a very close neighbor of the Milky Way. Advanced modeling technologies revealed that the galaxy appears to be dominated not by dark matter as long believed, but rather by a central black hole roughly 450,000 times the mass of the sun, according to a statement from the University of Texas McDonald Observatory.

"Our work may revolutionize the modeling of dwarf galaxies or star clusters to include supermassive black holes instead of just dark matter halos," Nathaniel Lujan, a graduate student at the University of Texas at San Antonio and lead author of the study, said in the statement.

Segue 1 is one of the Milky Way’s faintest companions, containing only a few hundred to a few thousand stars — far too few to generate enough gravity to stay intact. Astronomers have long assumed massive dark matter halos provide the gravity needed to keep such small galaxies intact.

However, when researchers modeled the motions of stars within Segue 1, the only simulations that matched observations from the W.M. Keck Observatory were those featuring a heavyweight black hole at the galaxy’s core. The models showed that the stars located near the center were traveling in quick, tight circles, which is a tell-tale sign of an immense gravitational pull generated by a black hole.

"The black hole in Segue 1 is significantly larger than what is expected,” Karl Gebhardt, a professor of astrophysicists at the University of Texas at Austin and co-author of the study, said in the statement. “If this large mass ratio is common among dwarf galaxies, we will have to rewrite how these systems evolve."

The newly discovered black hole outweighs all the galaxy's stars combined by about a factor of ten, which is uncommon among most galaxies in the universe, according to the statement.

Given Segue 1's proximity to the Milky Way, the researchers suggest that the dwarf galaxy may have once been larger, but lost most of its stars over time to the Milky Way’s tidal forces.

Segue 1 could also be a nearby counterpart to a newly discovered class of galaxies called "little red dots" — compact, early galaxies that formed with massive black holes and only a sprinkling of stars. While those distant systems are almost impossible to study directly, Segue 1 offers astronomers a rare chance to examine similar processes unfolding much closer to home.

Either way, the discovery challenges long-standing ideas about how small galaxies form and evolve — and reveals that even the faintest corners of the cosmos can harbor big surprises.

Their findings were published Oct. 14 in the Astrophysical Journal Letters.

What is it?

CMEs are among the most awe-inspiring explosions in the solar system. These vast eruptions hurl immense clouds of magnetized plasma from the sun's corona into interplanetary space, sometimes at millions of miles per hour.

Yet many of these powerful outbursts occur where we can't see them directly, on the far side of the sun, hidden from Earth's telescopes. These events still shape the solar wind environment that later sweeps past our planet or impacts other worlds, such as Venus and Mars.

That's where the Compact Coronagraph (CCOR-1) instrument aboard NOAA's GOES-19 weather satellite comes in. CCOR-1 blocks the sun's bright disk to capture faint white-light structures in the outer corona, tracking CMEs as they expand into space.

Where is it?

The CCOR-1 on NOAA's GOES-19 satellite orbits around 22,000 miles (36,000 kilometers) above Earth's equator.

Why is it amazing?

When aimed toward Earth, these sorts of eruptions can set off brilliant auroras, disrupt satellites and disturb power systems. Although no direct effects were felt on Earth with this particular CME, the event showed how powerful our sun can truly be.

CCOR-1's imagery offered a glimpse of "the storm we missed," one that, if rotated just a few days earlier, could have driven a major geomagnetic disturbance.

Want to learn more?

You can learn more about the solar cycle and weather satellites.

But much is unknown about the availability of water ice on the moon, or even what data is missing that could help fine-tune lunar exploration by both robotic probes and human explorers. That's why an upcoming meeting of international experts will meet to discuss today's state of knowledge regarding volatiles in the lunar polar regions.

The goal of the gathering in Honolulu, Hawaii is to help prepare for an onslaught of upcoming robotic and crewed expeditions by multiple nations to explore for, investigate and ultimately utilize lunar polar volatiles. This seminal meeting, the 2nd Lunar Polar Volatiles Conference, will take place Nov. 12-14 and invite attendees from throughout U.S. academia, and will also include presentations from China, Canada, and a number of private space companies.

What's missing?

"I think there are at least three aspects regarding lunar polar volatiles that we are missing," said conference organizer, Shuai Li of the Hawaii Institute of Geophysics and Planetology, University of Hawaii at Manoa.

First is the need for a comprehensive survey of major volatiles possibly present in the lunar permanently shadowed regions, or PSRs. That survey is critical and missing, Li told Space.com.

"For instance, water ice could be the most abundant volatile but we still have no robust mapping of it, particularly at many regions that may only harbor a few weight percent, or even less water ice," said Li. Other notable volatile species such as hydrogen sulfide, carbon monoxide or carbon dioxide could be much lower abundance than water ice.

"We do not have direct observations of such volatile species," Li said.

Secondly, there is a lack of knowledge on how volatiles distribute vertically, including water ice.

And thirdly, said Li, is the need for sampling of those volatiles to understand their origins and how they formed and sequestered on the moon.

Just getting started

Norbert Schörghofer, senior scientist at the Planetary Science Institute and resident in Honolulu, Hawaii, is a co-organizer of the upcoming gathering.

"In my view, the field of 'lunar polar volatiles' is just getting started," said Schörghofer. Many missions, such as the recently reinstated Volatiles Investigating Polar Exploration Rover, or VIPER, have been delayed, "and we don't have nearly enough data to assess the abundance and distribution of water ice on the moon," he told Space.com.

Most importantly we need definitive proof of ice on the moon, Schörghofer said.

Wanted: definitive and reproducible evidence

Back in October 2009, NASA's Lunar Crater Observation and Sensing Satellite (LCROSS), was purposely put on a "slam dunk" trajectory to confirm the presence of water ice in a permanently shadowed crater at the lunar south pole.

"LCROSS measured six percent, but that's not a lot of ice and it was a single-shot experiment," said Schörghofer. "And the spectroscopic detections of ice exposed on the surface from lunar orbiters are hopelessly incoherent. We need definitive and reproducible evidence," he told Space.com.

Schörghofer observed that there has been major progress regarding water inside of rocks, based on the return samples from China's Chang'e-5 and Chang'e-6 near side and far side missions.

"However, there has been shockingly little progress about ice, due to the lack of landed missions to the polar regions. Scientists are trying to tease out information about ice from data that were collected for other reasons, from instruments that were never designed to detect lunar volatiles, so we ended up with a lot of 'maybe' observations," said Schörghofer.

International collaboration

In terms of new research by multiple nations, how is international cooperation evolving? Is there a need for more collaboration between countries?

"Very slow in progress, but we can see the growth," responded Li.

A great step in collaboration has been between the US and South Korea's Korean Pathfinder Lunar Orbiter (KPLO) called Danuri that carries ShadowCam, an ultrasensitive camera provided by NASA/Arizona State University/Malin Space Science Systems to look inside PSRs on the moon.

Over the next decades, lunar exploration will be largely driven by the US and China, said Schörghofer.

"International collaboration is nice to have and broadens the scientific interest in the moon. The degree of cooperation will undoubtedly increase, but ultimately we are looking at a competition between two superpowers," Schörghofer said.

Share findings

There remains a lot of uncertainty about how much ice there is on the moon, and where exactly it is.

"Reserves, in the sense of known and readily recoverable resources, are hence arguably quite small at this point of time," Schörghofer said. "What we need is definitive measurements of the ice content," he emphasized.

"There is definitely a need for more collaboration internationally," Li added. "For instance, there will be many missions to the lunar south pole in the coming years. It will be super beneficial to all countries if they can share their findings about lunar volatiles, not only for science but also for in-situ resource utilization purposes," he concluded.

The sun is getting into the Halloween spirit once again. NASA's Solar Dynamics Observatory (SDO) captured a hauntingly festive view of our star on Oct. 28, looking like a cosmic jack-o'-lantern grinning down at Earth.

In the image, captured by SDO's Atmospheric Imaging Assembly (AIA), dark coronal holes and bright active regions combine to form what appears to be glowing eyes, a nose and a mischievous smile carved across the solar surface.

That "mouth" however, is more than just a decoration. It's actually a vast coronal hole, an area on the sun's surface where the magnetic field opens up, allowing charged particles (solar wind) to stream freely into space. This particular hole is currently spewing a high-speed solar wind stream toward Earth, which could spark minor (G1) to moderate (G2) geomagnetic storm conditions from Oct. 28 through Oct. 29, according to space weather forecasters.

If geomagnetic storm conditions intensify, auroras can spread beyond their usual polar locations, into mid-latitudes. 22 years ago this week, the infamous Halloween storms of 2003 saw a barrage of powerful solar eruptions trigger spectacular auroras and disrupt satellites and power systems worldwide.

SDO has been watching the sun since 2010, providing continuous, high-resolution views that help scientists understand how the sun's magnetic energy drives space weather, which in turn affects our lives here on Earth.

This isn't the first time the observatory has spotted a spooky face on the sun. Back in 2014, it captured this eerie jack-o'-lantern-like grin.

Siddharth Patel, a 12-year-old who lives in London, Ontario (west of Toronto), spotted two possible asteroids in September as part of a citizen science program that partners with NASA, according to the Toronto Star.

The two suspected space rocks are called 2024 RX69 and 2024 RH39 and are cataloged in the Minor Planet Center, which is a branch of the International Astronomical Union that reports and tracks asteroids and other small, naturally occurring space objects.

Siddharth told the Star he pursues his love of astronomy — he's been using a telescope since age five, supported by parents with no space background — after finishing school activities.

"Space was not really taught in schools," he said. "I really started doing things about space after I came back from school, because school is the academic time. And after that is the time when I pursue my interests and dreams."

While confirming the asteroids' orbits may take as long as a decade, Patel has another big project on his mind: becoming an astronaut. He recently joined the youth-focused Royal Canadian Air Cadets to learn how to fly a plane, the Star reported. This is following the pathway of notable Canadian Space Agency astronauts such as Jeremy Hansen (who will fly around the moon as part of NASA's Artemis 2 mission next year) and Chris Hadfield, the first Canadian to command the International Space Station.

Siddharth found the asteroids through the International Astronomical Search Collaboration, which uses images from the Hawaiian Pan-STARRS facility and the Arizona-based Catalina Sky Survey for asteroid searches. While Siddharth's two space rocks reside in the main asteroid belt between Mars and Jupiter, the collaboration can also find near-Earth asteroids and trans-Neptunian objects (which orbit the sun beyond Neptune), according to NASA.

The provisional asteroid discoveries aren't Siddharth's only space accolades. His image of Comet C/2023 A3 (Tsuchinshan-ATLAS) alongside the Milky Way received the People's Choice Award in DarkSky International's 2025 Capture the Dark photography contest.

"I love taking photos through my telescopes," Siddharth told the Canadian Broadcasting Corp. "When I go to somewhere dark, or someplace that has lots of stars, it really ignites my sense of wonder. I've learned how mysterious space really is."

The method, developed by researchers at the State University of Campinas in Brazil, uses images of dune surfaces to estimate the force acting on each grain of sand. By combining laboratory experiments, computer simulations and artificial intelligence (AI), the team generated detailed force maps that reveal the physics of dune formation.

Dunes, particularly crescent-shaped "barchan" dunes, form wherever wind or water flows over loose sand — from deserts and seabeds on Earth to the dusty plains of Mars. Scientists can track their movement to infer prevailing winds and environmental conditions, but measuring the forces driving each grain’s motion has, until now, been impossible, according to a statement from the university.

"To measure the force acting on each grain, you'd need to place a tiny accelerometer on each one, which simply doesn't exist," the researchers said in the statement.

To overcome this challenge, the team recreated miniature underwater dunes in a laboratory setting and ran detailed 3D simulations to calculate the exact forces acting on each grain. They then trained a convolutional neural network — a form of AI used for image recognition — to link dune images with corresponding "force maps" from the simulations. Once trained, the AI could infer the distribution of forces directly from visual data. When tested on new images, it accurately predicted the forces at play, even for dune shapes it hadn't seen before.

"Any granular system that can be seen in an image — whether ice, salt or synthetic particles — can be analyzed as long as there’s a simulation capable of accurately reproducing the behavior of the material," Renato Miotto, a postdoctoral researcher and lead author of the study, said in the statement.

The ability to extract such detailed physical information from images alone could have wide-ranging applications. On Earth, it may help engineers better predict coastal erosion, river sediment transport or the behavior of granular materials in industrial systems. This can also be applied to other planets imaged from orbit, like Mars, whose dunes evolve under the same basic physics as those on Earth.

"In the case of Mars, it’s possible to infer, from widely available images, the intensity of winds in the past and the evolution of dunes in the future," Erick Franklin, professor and co-author of the study, said in the statement.

This method therefore offers a new window into studying the Red Planet's atmospheric history and surface evolution. Their findings were published Aug. 1 in the journal Geophysical Research Letters.

The detection of the baby black holes and information about the four parent black holes that forged them came courtesy of ripples in spacetime, or gravitational waves, caused by the violent cosmic events that gave birth to them. Those waves were registered by the LIGO (Laser Interferometer Gravitational-Wave Observatory), Virgo, and KAGRA (Kamioka Gravitational Wave Detector) gravitational wave detectors.

The LIGO-Virgo-KAGRA collaboration detected the first merger, designated GW241011, on Oct. 11, 2024. It was the result of a black hole with around 17 times the mass of the sun crashing into its partner black hole with a mass around seven times that of our star. The event was calculated to have happened around 700 million light-years from Earth. Decoding the resultant gravitational wave signal revealed a couple of things: The masses of the black holes involved as well as the fact that the larger of the pair is one of the most rapidly spinning black holes ever observed.

Less than one month after this groundbreaking detection, on Nov. 11, 2024, the gravitational wave instruments "heard" another newborn black hole screaming after the violent collision of its progenitors. This signal, GW241110, originated from a collision between black holes with 16 and eight times the mass of the sun and occurred about 2.4 billion light-years away. This signal revealed that one of the black holes involved was spinning in the opposite direction of its orbit around the other black hole, the first time such a characteristic has been seen for merging binary black holes.

"Each new detection provides important insights about the universe, reminding us that each observed merger is both an astrophysical discovery but also an invaluable laboratory for probing the fundamental laws of physics," Carl-Johan Haster, an assistant professor of astrophysics at the University of Nevada, Las Vegas (UNLV), said in a statement. "Binaries like these had been predicted given earlier observations, but this is the first direct evidence for their existence."

Both events indicate the existence of so-called second-generation black holes.

"GW241011 and GW241110 are among the most novel events among the several hundred that the LIGO-Virgo-KAGRA network has observed," Stephen Fairhurst, LIGO Collaboration spokesperson and a Cardiff University professor, said in the statement. "With both events having one black hole that is both significantly more massive than the other and rapidly spinning, they provide tantalizing evidence that these black holes were formed from previous black hole mergers."

Black holes: the second generation

The idea that the detected black holes are second-generation comes from the difference in size between the larger black holes and their smaller companions in the two mergers. The more diminutive black holes appear to have been almost half the mass of their companions. The orbit-opposing orientation of the larger black hole's spin in the merger that produced the signal GW241110 is also evidence of a prior merger having produced that dominant black hole.

The process of black hole growth by collision after collision is known as "hierarchical merger." This is believed to occur in densely populated regions like star clusters, where black holes are more likely to meet and coalesce over and over again, resulting in subsequently larger black holes.

GW241011 offers scientists the opportunity to probe the limits of Albert Einstein's 1915 theory of gravity, general relativity, from which the concept black holes and gravitational waves both emerged.

For instance, the rapid rotation of the black hole involved in this particular merger deforms the object, and that leaves a unique impression in the gravitational waves it emits. This means that this event can be compared to general relativity and the predictions physicist Roy Kerr made using Einstein's theory concerning rotating black holes. The black holes of GW241011 conformed to Kerr's solution to general relativity, the study team explains, helping verify it as well as Einstein's magnum opus theory itself in extreme circumstances. This includes confirming for the third time within a gravitational wave signal (GW241011) the "hum" of a higher harmonic, akin to the overtones of musical instruments.

The LIGO-Virgo-KAGRA collaboration also thinks these gravitational wave signals could be key to unlocking something predicted but never before seen — something outside the limits of general relativity.

Plus, the two black hole mergers behind these signals have the potential to reveal more about an unrelated scientific field: particle physics.

Scientists can use rapidly rotating black holes to test the hypothesized existence of ultralight bosons, or particles that exist beyond the Standard Model of particle physics. Should they exist, ultralight bosons should draw the rotational energy from spinning black holes. How much energy these particles extract and how much they slow black holes down is dependent on their mass.

The revelation that the progenitor black hole of the merger behind GW241011 is still rotating at a rapid rate after millions (or even billions) of years since the merger that created it seems to rule out a range of ultralight boson masses.

"The detection and inspection of these two events demonstrate how important it is to operate our detectors in synergy and to strive to improve their sensitivities," Francesco Pannarale, co-chair of the Observational Science Division of the LIGO-Virgo-KAGRA Collaborations and professor at Sapienza University of Rome, said. "The LIGO and Virgo instruments taught us yet some more about how black hole binaries can form in our universe, as well as about the fundamental physics that regulates them at the very essence.

"By upgrading our instruments, we will be able to dive deeper into these and other aspects with the increased precision of our measurements."

The team's research was published on Tuesday (Oct. 28) in the Astrophysical Journal Letters.

The meteoritic debris found among the 1,935.3 grams (68.3 ounces) of lunar regolith sampled by Chang'e 6 belongs to a class of carbon- and water-rich meteorites known as CI (carbonaceous-Ivuna) chondrites. On Earth, these meteorites account for less than 1% of all collected space rocks; their most notable example is the Ivuna meteorite that fell in Tanzania in 1938. Out in space, however, it's a different story, with the asteroids Ryugu and Bennu, visited recently by Japan's Hayabusa2 mission and NASA's OSIRIS-REx, respectively, both displaying similarities to CI chondrites.

And these meteorites may also be relatively abundant on the moon.

"Based on the limited exogenous materials identified on the moon, CI chondrites seem to be more common there than on Earth," Mang Lin, a professor of isotope chemistry at the Guangzhou Institute of Geochemistry of the Chinese Academy of Sciences, told Space.com. "However, the current dataset is too small to draw any firm conclusions, and we'll need more measurements in the future to test this."

Chang'e 6 landed in the South Pole-Aitken Basin on the moon in June 2024 to bring back the first ever sample from the lunar far side. CI chondrites are fine-grained and highly porous, so they break apart easily and react with oxygen and water, which explains why they are so rare on Earth: because they break down or are chemically altered quickly. On the bone-dry moon, however, conditions are suited to preserving the chondrites.

Lin was part of a team led by Jintuan Wang and Zhiming Chen, both of whom also work at the Guangzhou Institute of Geochemistry, who identified unusual olivine-bearing fragments in Chang'e 6's sample. Through mass spectrometry, they found that the fragments contain levels of iron, manganese and zinc that imply that they are not native to the moon; a measurement of oxygen isotopes in the fragments subsequently confirmed that they are CI chondrites.

CI chondrite meteorites typically carry a wealth of volatiles, which are substances such as water and carbon dioxide that can exist as ice in the outer solar system and which have low boiling points. As such, they and other types of carbonaceous chondrites in general are considered as a possible source of water on Earth and the moon.

Yet their apparent presence in such significant quantities on the moon has come as a surprise to lunar scientists, and it suggests that there may have been more impacts of carbonaceous chondrite asteroids in the Earth-moon system in the distant past than had been thought. It's evidence that material formed in the cold of the outer solar system frequently found its way in-system to deliver water and other volatile gases to the inner planets.

"CI chondrites are certainly an important [water] carrier to consider because of their high volatile content," said Lin. "That said, there were probably multiple sources of water for both Earth and the moon, and we'll need more data in the future to really quantify how much each source contributed."

The findings were published on Oct. 20 in Proceedings of the National Academy of Sciences.

What is it?

Mounted on ESO's Visible and Infrared Survey Telescope for Astronomy (VISTA), 4MOST is designed to provide spectra for thousands of celestial sources at once, enabling astronomers to study the composition, temperature and motion of stars and galaxies across huge areas of the night sky.

Unlike traditional telescopes that observe one or a few objects at a time, 4MOST's engineering allows it to conduct massive, simultaneous surveys, seeing more things at one time. The instrument's wide hexagonal field of view covers a large portion of the sky in each observation, making it ideal for studying cosmic evolution and dark energy.

Where is it?

4MOST and the VISTA telescope are located at the Paranal Observatory in Chile.

Why is it amazing?

During its first observations, 4MOST turned its hexagonal gaze toward a region in the southern sky that includes two popular celestial targets: the Sculptor Galaxy (NGC 253) and the global cluster NGC 288. Each of the colored dots in the image represents a distinct object whose light was captured and analyzed by one of 4MOST's 2,400 fibers.

From each target, the instrument collected a spectrum, a detailed fingerprint of light that reveals key physical properties such as chemical composition, temperature, radial velocity and more.

Over the next decade, 4MOST will deliver millions of spectra, helping scientists tackle some of astronomy's biggest questions.

Want to learn more?

You can read more about the European Southern Observatory's recent research, as well as other telescopes in Chile.

It has previously been theorized that binary systems are hostile to the formation of complex planetary arrangements, meaning this discovery could change how we think about planet formation and the stability of worlds after formation. What makes the planets of TOI-2267 even more exciting is they also break some previously held exoplanet records.

Furthermore, the binary star nature of this system, located around 190 light-years from Earth, means these exoplanets could experience dual starsets reminiscent of the famous scene in Star Wars: A New Hope in which Luke Skywalker gazes dreamily out at the stars of his homeworld, Tatooine.

"Our analysis shows a unique planetary arrangement: two planets are transiting one star, and the third is transiting its companion star," Sebastián Zúñiga-Fernánde, study team member and a researcher at the University of Liège (ULiège), said in a statement.

"This makes TOI-2267 the first binary system known to host transiting planets around both of its stars."

Record breakers!

Binary star systems come in a range of shapes, sizes and arrangements. TOI-2267 is a "compact binary." This means the stars that comprise this system orbit each other in close proximity. This closeness causes gravitational instability that existing planetary formation models have suggested should result in an environment unsuitable for planet formation.

Yet, planets have formed in TOI-2267.

"Our discovery breaks several records, as it is the most compact and coldest pair of stars with planets known, and it is also the first in which planets have been recorded transiting around both components," Francisco J. Pozuelos, study team co-leader and a researcher at the Instituto de Astrofísica de Andalucía (IAA-CSIC), said in a statement.

Pozuelos and colleagues got their first hints about these three distant Earth-like worlds when they examined data from TESS using their detection software, SHERLOCK. This early indication of planets in the TOI-2267 system prompted the team to get ready for more observations with several other observatories. This included SPECULOOS, a network of robotic telescopes comprised of SPECULOOS Southern Observatory at the Paranal Observatory in Chile and SPECULOOS Northern Observatory at the Teide Observatory in Tenerife, and a pair of telescopes in Belgium called TRAPPIST (Transiting Planets and Planetesimals Small Telescope).

These facilities are specially adapted to investigate small exoplanets around cool and faint stars, meaning they were vital in allowing the team to characterize TOI-2267, and thus, discovering its surprising nature.

"This system is a true natural laboratory for understanding how rocky planets can emerge and survive under extreme dynamical conditions, where we previously thought their stability would be compromised," Pozuelos said.

The queries raised regarding planet formation by this system could be an investigation that is right in the wheelhouse of the James Webb Space Telescope (JWST) as well as the next generation of ground-based observatories. These instruments should allow astronomers to precisely measure the masses, densities and possibly even the atmospheric chemistry of the newly discovered planets of TOI-2267.

"Discovering three Earth-sized planets in such a compact binary system is a unique opportunity," Zúñiga-Fernández concluded. "It allows us to test the limits of planet formation models in complex environments and to better understand the diversity of possible planetary architectures in our galaxy."

The team's research was published on Friday (Oct. 24) in the journal Astronomy & Astrophysics.

The comet, called 3I/ATLAS, is the third known interstellar object that has come through our solar system. As it flies deeper into the solar system before leaving our cosmic neighborhood some time between Nov. 27, 2025 and Jan. 27, 2026, the International Asteroid Warning Network is kicking off a campaign to observe the comet.

The project will serve as a training ground to not only predict the orbit of 3I/ATLAS, but to perform astrometric measurements (meaning, tracking the comet's speed and motion in Earth's sky, relative to objects like stars.) This will be used to inform future observations of comets or asteroids that may be a threat to Earth.

The network notes that comets are especially hard to observe, because their tails and "atmospheres" (comas) make it difficult to estimate overall brightness — which in turn affects pathway predictions.

Knowing the pathway of an object allows astronomers to predict how close it will come to Earth. In this case, 3I/ATLAS is coming nowhere near us. But its relative proximity (roughly 1.8 astronomical units, or sun-Earth distances, at its closest) is good enough for observations by small telescopes.

"The campaign will target comet 3I/ATLAS (C/2025 N1) to exercise the capability of the observing community to extract accurate astrometry," read a notice of the project Tuesday (Oct. 21) at the Minor Planet Center, which is a branch of the International Astronomical Union that catalogs and tracks small objects in space.

Citizen scientists are welcome to join in. If you're interested, register at this link no later than Nov. 7—as the notice provides no time of day, we recommend registering as soon as feasible. The schedule includes a workshop on Nov. 10, and periodic teleconferences through and after the observing period.

The International Asteroid Warning Network calls itself a "worldwide collaboration of asteroid astronomers and modelers" and was formed following recommendations from the United Nations and its space mission planning advisory group "for an international response to the near-Earth object (NEO) impact threat."

NASA, like other parts of the U.S. government, is allowed to perform essential duties despite the ongoing government shutdown. Comet and asteroid observations are considered a priority item as there is a small chance one could pose a threat to Earth, so NASA continues to track and publish information about them.

The agency has undertaken decades of searching to see if there are any potentially hazardous objects threatening our planet. Despite dedicated examinations of the sky, no imminent threats have been found. But NASA and its network of partner telescopes continue the search — just in case.

Darryl Z. Seligman is an Assistant Professor of Physics and Astronomy at Michigan State University.

In a surprising discovery, our team has detected glowing nickel vapor in the gas surrounding the incoming interstellar comet 3I/ATLAS at an extraordinary distance from the sun, where temperatures remain far too cold for metals to normally vaporize. This unexpected finding provides new insights into the chemistry of materials from beyond our solar system.

On July 1, 2025, a routine sky survey by the Asteroid Terrestrial-impact Last Alert System (ATLAS) detected what would soon prove to be only the third confirmed interstellar object ever discovered. Unlike its predecessors — the enigmatic 'Oumuamua and comet Borisov — this new visitor, designated 3I/ATLAS, was caught early in its journey through our solar system, giving astronomers an unprecedented opportunity to watch an interstellar comet come to life as it approaches the sun.

What makes interstellar objects so scientifically valuable is that they carry chemical and physical information from the star systems where they formed, potentially billions of years ago. They're like cosmic time capsules, delivering samples from distant exoplanetary systems we could never otherwise visit and study directly. The discovery of 3I/ATLAS opens the door to a completely new branch of study in astrophysics.

For our international team using the Very Large Telescope (VLT) in Chile, 3I/ATLAS presented an extraordinary chance to track the chemical awakening of this ancient interstellar object in real-time. Our observations using both the X-shooter and UVES spectrographs on the VLT revealed a trajectory that suggested it formed billions of years ago, potentially making it significantly older than our own solar system.

From dormant to dynamic

As 3I/ATLAS journeys toward the sun, we've witnessed a fascinating sequence of chemical activation. Our first significant detection came on July 20, when our spectrographs recorded spectral lines consistent with atomic nickel vapor in the comet's tenuous atmosphere at a distance of 3.88 astronomical units (AU) from the sun, nearly four times Earth's distance from the sun.

This nickel detection was unexpected at such large distances, where temperatures remain extremely cold. As the comet continued its approach, we observed that the amount of nickel vapor coming off of the comet was strengthening significantly. Our measurements indicated that there was a substantial increase in the amount of nickel atoms coming off of the comet as it approached the sun.

About three weeks later, by mid-August, when 3I/ATLAS had reached about 3.07 AU from the sun, we detected the spectral signature of cyanogen (CN) gas, a common molecular emission in solar system comets.

Chemical clues from another world

What makes these observations particularly intriguing and puzzling is the detection of nickel without concurrent detection of iron above our instrumental limits. This unusual chemical signature suggests the nickel is potentially being released through processes that work at much lower temperatures, rather than through the direct transformation of solid metal directly into gas (a process called sublimation), which would normally require much higher temperatures.

The evidence points to the possibility that nickel atoms might be bound within special types of molecules that break apart easily when exposed to sunlight. These could include molecules where nickel is attached to carbon monoxide or other organic compounds, which can release nickel atoms at much lower temperatures than would be needed for metal to vaporize directly.

These findings, when considered alongside observations from the James Webb Space Telescope (JWST), provide complementary evidence for understanding this comet's unusual chemistry. JWST observations revealed that the cloud of gas surrounding the comet, called the coma, contains much more carbon dioxide (the same gas that makes soda fizzy) than water, a ratio that is unusual compared with most solar system comets. JWST also detected water ice particles and carbon monoxide gas in the comet's coma, suggesting a complex mix of frozen materials that are warming up and creating the activity we observe.

Such observations suggest the nickel may be bound in molecules that break apart under solar radiation, releasing both metals and gases in chemical reactions. But the detailed balance of carriers, their release mechanisms, and how iron and other metals fit into the picture remain active areas of analysis.

Cosmic implication

As 3I/ATLAS continues its journey toward perihelion (its closest approach to the sun) on Oct. 29, we're gathering valuable data on the chemistry of material from another star system. The chemical signatures we're observing may reflect both the comet's ancient origins and its long journey through interstellar space.

These observations help us understand whether the building blocks of planetary systems are similar throughout the galaxy or if they vary significantly between different stellar environments. By comparing 3I/ATLAS with solar system comets and the previous interstellar visitor 2I/Borisov, we're building a more complete picture of the materials that form planets around different stars.

The beauty of science lies in following the evidence where it leads us, even when findings challenge our expectations. Our observations of 3I/ATLAS reveal natural astrophysical processes that, while unusual, can be explained through chemistry and physics. The universe continues to surprise us with its diversity and complexity, reminding us why methodical, evidence-based research remains our most reliable path to understanding cosmic mysteries.

Future outlook

Our international team, including scientists from Chile, Belgium, the U.K., Canada, New Zealand, the United States, and Italy, continues to monitor 3I/ATLAS as it approaches perihelion. We expect further increases in activity and potentially new chemical species to emerge as temperatures rise.

With coordinated observations from ground-based telescopes and space observatories, we hope to unlock more secrets from this cosmic messenger before it departs our solar system forever, carrying its ancient material back into the vast interstellar void.

Central to Europe's efforts are two major initiatives: the Argonaut lunar lander and LUNA, a lunar simulation and training facility.

What is it?

Argonaut is ESA's dedicated lunar lander program, Europe's planned autonomous, versatile and reliable transport system to the moon. The Argonaut will deliver up to 1.6 tons (1.5 tonnes) of cargo to virtually any location on the lunar surface.

The lander's cargo will include essential supplies for the astronauts, food, water and oxygen, along with scientific instruments, communication systems, power generation units and even rovers.

Unlike the Apollo missions of the past, Argonaut is being designed to survive the two-week lunar night, when temperatures plummet to -274 degrees Fahrenheit (-170 degrees Celsius).

Where is it?

This image was taken in the LUNA facility near Cologne, Germany.

Why is it amazing?

To test the robustness of Argonaut, the ESO and German Aerospace Center (DLR) established LUNA, an advanced lunar analog facility in Germany. This "moon on Earth" serves as both a research laboratory and astronaut training ground, designed to mimic many of the extreme conditions found on the surface of the moon.

The deep floor of the LUNA testbed allows for sampling and drilling up to nine feet (three meters) below the surface, enabling scientists and engineers to test technologies for resource extraction, mobility and construction. The facility also replicates the moon's intense sunlight, harsh shadows and dust-laden environment, providing a realistic setting for testing equipment like Argonaut.

Want to learn more?

You can learn more about lunar simulations and lunar landers.

The European Space Agency (ESA) staged the exercise at its mission control center in Darmstadt, Germany, to test how its satellites and operations teams would respond to a solar superstorm rivaling the 1859 Carrington Event — the most powerful geomagnetic storm ever recorded, capable of causing severe electronic disruption. The simulation was designed to test spacecraft operations and space weather preparedness ahead of the upcoming Sentinel-1D mission, set to launch in November.

"Should such an event occur, there are no good solutions. The goal would be to keep the satellite safe and limit the damage as much as possible," Thomas Ormston, Deputy Spacecraft Operations Manager for Sentinel-1D, said in a statement from ESA.

In the simulation, the sun unleashed a triple threat. First came an enormous X-class solar flare, whose radiation hit Earth within eight minutes, disrupting communications, radar and tracking systems. A barrage of high-energy protons, electrons and alpha particles followed, striking spacecraft in orbit, triggering false readings, data corruption and potential hardware damage.

Then, about 15 hours later, a massive coronal mass ejection (CME) slammed into Earth's magnetic field. The planet's upper atmosphere swelled, increasing drag on satellites by up to 400%, knocking them from predicted orbits, heightening the risk of collisions and shortening the spacecraft's longevity.

On the ground, the same storm could overload power grids and pipelines with geomagnetic energy. The simulation forced ESA's mission controllers to make real-time decisions, offering insight on how to plan, approach and react when such an event occurs.

"The immense flow of energy ejected by the sun may cause damage to all our satellites in orbit," Jorge Amaya, Space Weather Modelling Coordinator at ESA, said in the statement. "Satellites in low-Earth orbit are typically better protected by our atmosphere and our magnetic field from space hazards, but an explosion of the magnitude of the Carrington event would leave no spacecraft safe."

The exercise demonstrated how a severe solar storm could cascade across systems, from satellite failures to degraded navigation, to the loss of critical communications. ESA scientists warned that such an event is inevitable.

"The key takeaway is that it's not a question of if this will happen but when," Gustavo Baldo Carvalho, Lead Simulation Officer of Sentinel-1D, said in the statement.

To prepare for the inevitable, ESA is expanding its monitoring network and preparing for the 2031 Vigil mission — a new spacecraft that will sit at the sun-Earth L5 point to give earlier warnings of incoming solar eruptions. The goal, officials say, is to ensure that spacecraft and ground infrastructure can recover quickly.

As the collapsed core of a massive star, a neutron star is a small but incredibly dense object, packing up to three times the mass of our sun into a small volume. Models predict that neutron stars are about a dozen or so miles across, but their exact radius has always been unclear.

"Measuring the properties of neutron-star matter is indeed very hard and this is because while we can measure the mass of a neutron star very accurately, it is very hard to measure its radius accurately," Luciano Rezzolla, a professor of theoretical astrophysics at the University of Frankfurt, told Space.com.

Rezzolla and his Frankfurt colleague, Christian Ecker, have now made things a little clearer with their new study into the compactness of neutron stars.

There are several reasons why it's difficult to determine the radius of a neutron star. One obstacle is that all the known neutron stars are very far away, but the main challenge revolves around what physicists call the equation of state. This describes the density and pressure within the interior of a neutron star, from which the radius and other properties can be accurately derived.

The trouble is, the conditions inside a neutron star are so extreme that they push our understanding of nuclear physics to the limit. A spoonful of neutron star material can weigh billion tons. Under that intense pressure, atoms are crushed and positively charged protons merge with negatively charged electrons to produce an object full of neutrons.

But at the heart of a neutron star, exotic physics may prevail: for example, "strange" matter particles called hyperons may exist, or perhaps the immense gravity causes even neutrons to mush together and force the quark particles they are made from flow almost freely. There's no way to test any of this, however, because scientists are unable to replicate the conditions inside a neutron star in a laboratory on Earth. It's just too extreme.

So, rather than there being one equation of state for neutron stars, there is a whole list of possible equations of state, one for each model describing possible conditions inside a neutron star.

To assess how compact a neutron star can become, Rezzolla and Ecker considered tens of thousands of equations of state. To make things more manageable, however, they looked at only the most massive neutron star possible in each case.

"A well-known result in general relativity is that for each equation of state there is a maximum mass allowed," said Rezzolla. "Any mass larger than the maximum mass would lead to a black hole. We know from observations that the maximum mass allowed should be somewhere between two and three solar masses."

Rezzolla and Ecker were surprised to find that an upper limit exists for the compactness of a neutron star, and that based on this, the ratio between the neutron star's mass and its radius is always smaller than 1/3.

This ratio can be determined thanks to what are known as geometrized units, which are commonly used in the physics of general relativity and allow mass to be expressed in length rather than weight.

"Because we set an upper limit on the compactness, we can set a lower limit on the radius," said Rezzolla. "Once we measure a neutron star's mass, we could say that its radius should be larger than three times its mass."

Rezzolla and Ecker also found that this ratio holds for all equations of state regardless of what their maximum mass is. This might at first seem surprising since one would automatically think that the most massive neutron stars would be the most compact because they'd have stronger gravity trying to make them contract. Instead, the exotic nuclear physics at play within neutron stars seems to override this and balance things out.

The relation is derived partially from the principles of quantum chromodynamics, or QCD, which is the theory of how the strong force binds particles called quarks to form particles such as neutrons. The strong force is carried by particles called gluons (the name coming from the fact that they glue quarks together) and QCD is the quantum field theory that governs them, giving them a quantum number whimsically known as "color charge."

Rezzolla and Ecker applied certain standard assumptions based on QCD to derive their compactness relation — they describe it as QCD leaving an "imprint" on the interior structure of neutron stars. This means that if it ever becomes possible to measure the radius of a neutron star precisely, then any deviation from this relation would be a big clue that something is amiss with our understanding of QCD.

"If we were to see a violation of this result, such as a neutron star with a compactness greater than 1/3, then this would indicate that there is something wrong in the QCD assumptions that we have employed," said Rezzolla.

It may be that we won't have to wait too much longer to be able to make an accurate observation of a neutron star's radius, whereby this relation and QCD could subsequently be tested. Rezzolla describes the prospects as "optimistic" and cites the NICER (Neutron star Interior Composition Explorer) experiment on the International Space Station, and also measurements from gravitational wave events, some of which involve the merger of a black hole with a neutron star. Only in one case so far, GW 170817, have two neutron stars been involved in a merger.

"If we could only see more events like GW 170817, we could set much tighter constraints on the possible radii of neutron stars,” said Rezzolla.

Rezzolla and Ecker's research is published in a on the pre-print paper repository arXiv.

Led by scientists at Rice University in Houston, the study suggests Jupiter's early growth cut off the flow of gas and dust toward the inner solar system, preventing the material that would one day form Earth, Venus and Mars from spiraling into the sun. In doing so, scientists say the planet's gravity not only stabilized the inner planets' orbits but also shaped the structure of the solar system, carving out rings and gaps that influenced how, and when, rocky bodies formed.

"Jupiter didn't just become the biggest planet — it set the architecture for the whole inner solar system," study co-lead Andre Izidoro, an assistant professor of Earth, environmental and planetary sciences at Rice University, said in a statement. "Without it, we might not have Earth as we know it."

Using computer simulations, Izidoro and his colleagues modeled how Jupiter's rapid growth in its first few million years affected the swirling disk of gas and dust that surrounded the newborn sun. The results show that Jupiter's massive gravity created ripples in the disk, disturbing the gas and forming ring-like bands of material that acted like "cosmic traffic jams," the statement says.

Scientists say those dense rings trapped small dust grains that would otherwise have spiraled into the sun, allowing them to clump together to form the rocky building blocks of planets.

According to the new study, as Jupiter grew and opened a wide gap in the disk, it effectively divided the solar system into inner and outer zones, preventing material from mixing freely between them. This barrier preserved the distinct footprints of elements called "isotopic" signatures found in meteorites — one type from the inner solar system, another from the outer — while also creating new regions where planetesimals could form much later.

"Our model ties together two things that didn't seem to fit before — the isotopic fingerprints in meteorites, which come in two flavors, and the dynamics of planet formation," Baibhav Srivastava, a graduate student at Rice University who co-led the study along with Izidoro, said in the same statement.

The study also explains why some primitive meteorites formed millions of years later than the first solid bodies in the solar system.

These later-born meteorites, known as chondrites, are considered among the most pristine materials in existence because they contain tiny molten droplets, called chondrules, that preserve the chemical record of the solar system's earliest days.

"The mystery has always been: Why did some of these meteorites form so late, 2 to 3 million years after the first solids?" Izidoro said in the statement. "Our results show that Jupiter itself created the conditions for their delayed birth."

By shaping the disk and halting the inward flow of material, Jupiter likely caused a second generation of planetesimals to form later, some of which became the chondritic meteorites that still fall to Earth today, the study notes.

The same kinds of rings and gaps predicted in the team's models are now observed in young star systems with the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile, supporting the idea that giant planets sculpt their surroundings as they form.

"Our own solar system was no different," Izidoro said in the statement. "Jupiter's early growth left a signature we can still read today, locked inside meteorites that fall to Earth."

The findings are detailed in a paper published Oct. 22 in the journal Science Advances.

The comet, called 3I/ATLAS, is sending out a jet of material towards the sun as our nearest star warms up some of its surface. The composite image shows the nucleus or icy, rocky central core of 3I/ATLAS as a large and black dot, along with a white glow — the comet's coma, or atmosphere. The jet is marked in purple and is blasting off towards the direction of the sun, which is typical behavior of comets in the solar system as well.

3I/ATLAS is only the third known interstellar object that has come through our solar system, and is rapidly hurtling towards the sun for its closest approach on Oct. 30. The comet will come within 1.8 astronomical units (sun-Earth distances) of our planet, making it visible in small telescopes before disappearing again into the dark.

Astronomers received notice of the jet Oct. 15 in the Astronomer's Telegram, an announcement service for the astronomy community with editor-in-chief Robert Rutledge, an associate professor at Montreal's McGill University.

Footage of the jet was captured on Aug. 2, and combines 159 exposures of 50 seconds each. It was taken with the Two-meter Twin Telescope at Teide Observatory in Tenerife, which is in the Canary Islands.

"This is the usual," Miquel Serra-Ricart, astrophysicist and chief science officer at the Light Bridges private research institution, which co-manages Teide, told our sister site LiveScience in an email. Serra-Ricart was the individual who posted the new images, which are not yet peer-reviewed; he pointed out that the comet’s tail is also pointing away from the sun, which is typical of these icy objects.

While comets do warm up when they get close to the sun, they don't warm up in all spots in the same fashion. The areas facing the sun heat up fastest, and if there is a weaker area on the surface of the comet, sublimated gases under the surface can burst through — causing these sun-facing jets.

Serra-Ricart estimated the jet could be as far as 6,200 miles (10,000 km) from 3I/ATLAS' surface, which is more than twice the equivalent distance across the largest part of the United States. The jet is likely made up of carbon dioxide and dust particles—just like what was spotted by NASA's James Webb Space Telescope back in August.

These jets can begin to fan out as the nucleus of the comet rotates. Some of the material will stay in the coma, while the rest will fall into the comet's tail after pressure from the sun — known as the solar wind — forces it there. Solar system comet C/2020 F3 NEOWISE, which was visible to the naked eye, showed just that kind of behavior back in 2020 in Hubble Space Telescope images.

Three billion years ago, a sun-like star reached the end of its life, throwing off its outer layers following its red giant phase to leave behind its inert core, which we see today as the white dwarf called LSPM J0207+3331, located 145 light-years away. But what happened to its planets?

Spectroscopic observations of LSPM J0207+3331 by several telescopes, including the Magellan Baade 6.5-meter telescope in Chile and the 10-meter Keck I telescope on Hawaii's Mauna Kea, have revealed that fragments of planets and asteroids have survived for three billion years.

For one of those fragments, however, its time is at an end. The spectroscopic observations have shown that gravitational tidal forces from the white dwarf have torn it apart, scattering debris from the planetary body onto the surface of the white dwarf. The measurements identified 13 elements from this doomed object, including aluminum, carbon, chromium, cobalt, copper, iron, magnesium, manganese, nickel, silicon, sodium, strontium and titanium, in mostly Earth-like abundances.

The white dwarf features a hydrogen-rich envelope, and in general any elements deposited onto the white dwarf should sink into this hydrogen envelope and disappear from view. For so many elements to still be visible implies that their accretion onto the white dwarf must have happened relatively recently — within the past 35,000 years.

It could even be ongoing – LSPM J0207+3331 could still be dismantling this object, which is estimated to have been 120 miles (193 kilometers) across, a piece at a time as you read this.

Heavy elements from destroyed planets and asteroids have been detected on white dwarfs before, but after three billion years this process of debris falling onto the white dwarf should have ended.

"The amount of rocky material is unusually high for a white dwarf of this age," said Patrick Dufour of the Trottier Institute for Research on Exoplanets at Université de Montréal in a statement.

LSPM J0207+3331 is also ringed by a probable debris disk rich in silicates and which was discovered as an excess mid-infrared glow by NASA's Wide-field Infrared Survey Explorer (WISE). The hypothesis is that the object that has recently been ripped apart by the white dwarf could have originated from this debris disk of material that survived the death of the star. Future James Webb Space Telescope (JWST) observations of this disk could allow researchers to determine its mineralogy and constrain its total mass, which will provide further clues as to the nature of the object that the white dwarf has destroyed.

What is not yet clear is why has this object met its doom now, and not at any time in the previous three billion years?

"This discovery challenges our understanding of planetary system evolution," added Érika Le Bourdais, also of Montréal and the lead author of the research. "Ongoing accretion at this stage suggests white dwarfs may also retain planetary remnants still undergoing dynamical changes."

When a sun-like star begins to die and expands into a red giant, its inner planets are consumed and destroyed. However, bodies orbiting far enough away, such as asteroids, comets and gas giant planets, can survive, after a fashion. The changing gravitational field as a star sheds mass can disrupt the planets' orbits, resulting in many collisions between asteroids, comets and surviving planets and moons over billions of years that can grind solid bodies down to dust and small chunks. It's this material that fills the debris disk around LSPM J0207+3331, and what is surprising is that substantial solid bodies still exist in that disk, and that something must have happened to cause one of those solid bodies to fall towards the white dwarf.

"Something clearly disturbed this system long after the star's death," said John Debes of the Space Telescope Science Institute. "There's still a reservoir of material capable of polluting the white dwarf, even after billions of years."

What has destabilized the debris is unclear. Any surviving gas giant planets could be responsible, with multi-planet interactions having possibly gradually destabilized orbits of smaller bodies over billions of years. "This could point to long-term dynamical processes we don’t yet fully understand," said Debes.

Proving this idea won't be easy, however.

Gas giant planets would be too far from the white dwarf and likely too cool to be bright enough to be imaged, although the JWST might be able to have a go. More likely, the European Space Agency's Gaia astrometric mission may have been able to detect a wobble in the motion of the white dwarf on the sky caused by the gravity of orbiting gas giant planets pulling on it. The first batch of exoplanet data from Gaia is expected to be released in December 2026 – perhaps then the mystery might be solved?

The findings have been published on Oct. 22 in The Astrophysical Journal.

A satellite image captures the demolition of the historic East Wing of the White House in order to make room for a planned new ballroom.

The image was taken by Planet's SkySat satellite constellation on Oct. 23, 2025 from high above the White House in Washington, D.C. It shows the East Wing of the White House reduced to a pile of rubble as construction continues on the new Trump ballroom, a planned 90,000-square-foot (8,360-square-meter) event space that will have room for over 900 guests.

When complete, the ballroom will be nearly twice the size of the White House itself. The addition will cost $300 million, according to the Associated Press.

President Trump issued a statement via social media that says the ballroom is "being privately funded by many generous Patriots, Great American Companies," as well as by the President himself.

According to a list provided by the White House, donors include a number of individual donors as well as corporations such as Amazon, Google, Microsoft and Lockheed Martin, who manufacture the Orion spacecraft for NASA's Artemis program.

The construction has faced criticism from groups such as the National Trust for Historic Preservation, a privately funded nonprofit organization devoted to preserving historic buildings and locations within the United States. In a letter published Oct. 22, Carol Quillen, President and Chief Executive Officer of the National Trust, urged the Trump Administration and the U.S. National Park Service to stop the demolition until the administration's plans could go through the "legally required public review processes."

Quillen also wrote that the National Trust is "deeply concerned that the massing and height of the proposed new construction will overwhelm the White House itself" and "may also permanently disrupt the carefully balanced classical design of the White House with its two smaller, and lower, East and West Wings."

The East Wing of the White House was built in 1902 by President Theodore Roosevelt as a formal entrance for guests and visitors. It was later expanded in 1942 under the Franklin D. Roosevelt administration in order to conceal the construction of an emergency bunker. A small movie theater was added that same year.

In the 1930s, First Lady Eleanor Roosevelt began using the East Wing to host guests, according to the New York Times, beginning a long tradition of the first ladies using the wing for official functions and their own offices.

First Lady Melania Trump has yet to issue a statement on the East Wing's demolition, and has declined requests for comment from media outlets.

Rubin's mission is to survey the entire southern sky every three nights, using its 8.4-meter Simonyi Survey Telescope and a record-breaking 3.2 gigapixel LSST Camera, the largest digital camera.

What is it?

This image captures the Rubin Observatory beneath a dazzling sweep of the southern Milky Way galaxy, with the Large Magellanic Cloud glowing softly to the left. The Milky Way's arc above mirrors the vast field Rubin will soon observe in exquisite detail, night after night, as it builds the most comprehensive record of the changing night sky ever attempted.

Where is it?

The Rubin Observatory is located at the summit of Cerro Pachón in the Chilean Andes mountains.

Why is it amazing?

Now that it's fully operational, Rubin is embarking on a 10-year-long survey, known as the Legacy Survey of Space and Time (LSST), which will record the positions, brightness and motions of billions of celestial objects. The amount of data it will collect is so large that astronomers working at the observatory need an electronic 'data butler' to help manage the telecope's images.

Using its camera, Rubin will detect up to 10 million transient changes in the sky every single night, from asteroids to supernovas.

Want to learn more?

You can learn more about the Vera C. Rubin Observatory and other ground-based telescopes.

The asteroid, called 2025 SC79, has a pathway within the orbit of Venus that zips around the sun in only 128 days, making it the second-fastest unique asteroid orbit in the solar system, according to a statement from Carnegie Science. 2025 SC79 is also a pretty big asteroid: roughly 0.4 miles (700 meters) long, or roughly the length of a skyscraper.

Carnegie astronomer Scott Sheppard, a noted discoverer of small moons around Jupiter, Saturn, Uranus and Neptune, spotted the asteroid on Sept. 27 hiding in the sun's glare. While 2025 SC79 will make no close approaches to Earth for the foreseeable future, finding hidden asteroids is essential for protecting our planet, Sheppard emphasized in the statement. "The most dangerous asteroids are the most difficult to detect," Sheppard said. "Most asteroid research finds these objects in the dark of night, where they are easiest to spot. But asteroids that lurk near the sun can only be observed during twilight—when the sun is just about to rise or set. If these 'twilight' asteroids approach Earth, they could pose serious impact hazards."

Sheppard and his team also previously found the fastest-known asteroid, 2021 PH27, which circles the sun in only 113 days — less than a third of a year on Earth. His research into twilight asteroids, which includes financial support from NASA, uses the Dark Energy Camera at the National Science Foundation's (NSF) Víctor M. Blanco 4-meter telescope in Chile.

The new asteroid was confirmed by NSF's Gemini Observatory (which has locations in Hawaii and Chile) as well as Carnegie Science's twin Magellan Telescopes in Chile. News of 2025 SC79's discovery was brought to the astronomy community Oct. 15 in a circular from the Minor Planet Center, a branch of the International Astronomical Union that shares information on small, natural bodies in space.

Follow-up observations of 2025 SC79 will need to wait several months as it is now behind the sun, from Earth's perspective. "Future research of this object will reveal details about its composition—and how it survives the intense heat of its proximity to the Sun—as well as its possible origin," Carnegie officials stated.

Sheppard added following up observations of this type of asteroid has a lot of merit, because it helps astronomers understand how perturbations in small-body orbits, caused by gravity of other objects like planets, can make the pathway veer over the eons. "Understanding how they [asteroids] arrived at these locations can help us protect our planet, and also help us learn more about solar system history."

Astronomers keep close watch on asteroids in the sky, including "potentially hazardous" asteroids that in the statistical sense, are deemed a little more worrisome. After decades of careful searching, however, no imminent threats to our planet have been found.

NASA and a network of telescopes keep searching just in case—with the work being deemed so essential that findings continue to be published this month despite the ongoing U.S. government shutdown.

Scientists say they may be one step closer to confirming the existence of this elusive material, thanks to new simulations suggesting that a faint glow at the center of the Milky Way could be dark matter's long-sought signature.

"It's very hard to actually prove, but it does seem likely," Moorits Muru of the Leibniz Institute for Astrophysics Potsdam in Germany, who led the new study, told Space.com.

Dark matter, which makes up about 27% of the matter in the universe, remains one of the biggest riddles in cosmology. It doesn't absorb or reflect light, making it completely invisible to telescopes. Despite decades of experiments, from underground particle detectors to orbiting space observatories, scientists have never detected it directly. Now, however, new computer simulations from Muru's team may have brought us a step closer to decoding the mystery.

The findings, show that dark matter near the Milky Way's center might not form a perfect sphere as scientists long thought. Instead, it appears flattened, almost egg-shaped, and that shape closely mirrors the pattern of mysterious gamma rays observed by NASA's Fermi Gamma-ray Space Telescope.

This builds on research dating back to 2008, when Fermi first spotted a broad, hazy glow of high-energy light near the galactic core, stretching across some 7,000 light-years. The signal was far brighter than existing models could explain.

Some scientists proposed that these rays could be the by-product of invisible dark matter particles known as WIMPs (short for weakly interacting massive particles) colliding and annihilating one another. Others argued they came from fast-spinning stellar remnants known as millisecond pulsars — ancient, rapidly spinning neutron stars that emit beams of radiation like cosmic lighthouses.

The pulsar theory made sense because the gamma-ray glow appeared flattened and bulging, much like the Milky Way's star-filled central region. If dark matter were behind the glow, scientists had expected a smoother, rounder pattern.

Muru and his team decided to put both ideas to the test. Using powerful supercomputers, they recreated how the Milky Way formed, including billions of years of violent collisions and mergers with smaller galaxies. Those violent events, the researchers found, left deep "fingerprints" on the way dark matter is distributed in the galactic core.

When this complex history is factored in, the simulated dark matter halo no longer looks spherical. Instead, it takes on a flattened, egg-like form — matching the pattern of gamma-ray emission Fermi has observed, the new study reports.

"We're showing that dark matter also has this flattened shape," Muru said. "So, it does match the [gamma ray] excess much better than expected before."

The finding suggests that dark matter could still be a strong contender behind the Milky Way's mysterious glow. But it doesn't completely rule out pulsars, the researchers say. Both possibilities, the team concludes, are now "essentially indistinguishable."

If the excess truly arises from dark matter collisions, it would mark the first indirect evidence that WIMPs, a leading dark matter candidate, really exist.

Definitive answers could come by the late 2020s, when the Cherenkov Telescope Array Observatory (CTAO) begins scanning the skies from its twin sites in Chile and Spain. The facility will be able to observe gamma rays at much higher resolution than Fermi, researchers say, potentially helping them distinguish between a swarm of pulsars, which have higher energies, and lower-energy annihilating dark matter particles.

Muru added that gamma-ray observations of smaller dwarf galaxies orbiting the Milky Way, whose cores also host dark matter in dense pockets, could further test both possibilities.

"That's where we hope to measure the signal," said Muru. "We're really looking forward to these observations."

Scientists are convinced dark matter is out there. The quest to detect it arguably remains both one of the most frustrating and most exhilarating challenges in modern physics.

"For some reason, it still eludes us," Muru said. "And I think the mystery makes it even more interesting."

The results were detailed in a paper published Oct. 16 in the journal Physical Review Letters.

Galaxy clusters — the largest gravitationally bound structures in the universe — act as cosmic signposts that trace the distribution of dark matter and the mysterious dark energy driving the universe's accelerated expansion. Each containing hundreds to thousands of galaxies, these clusters' characteristics such as size depend on how cosmic structures form and evolve. Thus, they're a powerful test of cosmological models.

The new catalog of galaxy clusters was assembled using six years of data collected by the Dark Energy Survey (DES). The project leveraged a powerful Dark Energy Camera (DECam) mounted to the 4-meter Blanco Telescope in Chile to provide one of the most detailed looks yet at how matter clumps together across cosmic time, according to a statement from the University of Chicago.

Observations from the DES revealed tens of thousands of clusters spanning billions of light-years, giving scientists a vast dataset to measure how structure grows. The DES team used optical and near-infrared observations from the DECam to detect faint galaxies and estimate their distances, building a 3D picture of the cosmic web.

One of the main goals was to see whether the universe today behaves as predicted by the leading cosmological model, known as Lambda-Cold Dark Matter (LCDM). For years, scientists have debated a mild mismatch — the so-called "S8 tension" — between how strongly matter appears to clump in the present-day universe versus how it should based on early-universe data from the cosmic microwave background.

"Our results find that the Lambda-CDM model describes the observable universe well," Chun-Hao To, lead author of the study from the University of UChicago, said in the statement.

Because dark matter and dark energy cannot be observed directly, scientists use massive clusters to better understand these mysterious forces, which are known to push galaxies together or apart. And because clusters are so massive, it's easier to see the effects of dark matter and dark energy on them than it would be on smaller objects, the researchers said.

Creating the new catalog required careful modeling of how clusters overlap and how their masses are estimated. Future telescopes like the Vera C. Rubin Observatory and NASA’s Nancy Grace Roman Space Telescope will probe much deeper. As those observatories come online, astronomers expect to expand the catalog dramatically, tracking how clusters formed across more of the universe’s history.

For now, the new DES galaxy cluster catalog offers one of the clearest maps yet of the cosmic landscape. Their findings were published Sept. 18 in the journal Physical Review D.

Now, 2060 Chiron, better known as just Chiron, is the latest celestial body to join the party. In analyzing observations of Chiron taken by Brazil's Pico dos Dias Observatory in 2023, astronomers have just spotted four rings plus diffuse material around this icy centaur, which was first sighted in 1977.

Centaurs are a class of celestial objects that are a cross between comets and asteroids, located between Jupiter and Neptune. Chiron, which orbits the sun between Saturn and Uranus, is composed of rock, water ice, and organic compounds, and it's approximately 125 miles (200 kilometers) in diameter.

Its rings — thought to be made of water ice and rocky material, potentially from a collision between Chiron and another celestial body — circle the centaur at approximately 170 miles (273 km), 202 miles (325 km), 272 miles (438 km) and 870 miles (1,400 km) from its center. The distant fourth ring, researchers note, might not ultimately be stable enough to be considered a ring, so further observations are necessary.

What's special about Chiron's rings is that they're still forming; this marks the first time astronomers have ever seen a ring system under formation. By comparing the 2023 observations to previous ones from 2022, 2018, and 2011, researchers determined that the ring system has been evolving rapidly.

"It is an evolving system that will help us understand the dynamical mechanisms governing the creation of rings and satellites around small bodies, with potential implications for various types of disk dynamics in the universe," astronomer Braga Ribas of the Federal University of Technology-Parana and the Interinstitutional Laboratory of e-Astronomy in Brazil, who co-authored a study on the research, told Reuters.

The team's research was published in the Astrophysical Journal Letters on October 14, 2025.

The planet, known as GJ 251c, orbits a red dwarf star 18.2 light-years away in the constellation of Gemini, the Twins. The planet's mass is four times greater than that of Earth, making it a 'super-Earth' — a rocky planet larger and more massive than our own.

"While we can't yet confirm the presence of an atmosphere or life on GJ 251c, the planet represents a promising target for future exploration," said Suvrath Mahadevan, who is a professor of astronomy at Penn State University, said in a statement.

In the habitable zone, sometimes referred to as the Goldilocks zone, conditions are just right for liquid water to exist on the surface of a planet with an appropriate atmosphere.

GJ 251c was discovered thanks to observations spanning over 20 years, during which scientists looked for a slight wobble of the world's parent star incurred by the planet's gravity. As the star wobbles ever so slightly toward and away from us, we see a Doppler shift in its radial velocity that can be measured with a spectrograph.

One other planet is known to exist in the system, GJ 251b, which was discovered in 2020 and orbits its star every 14 days at a distance of 7.6 million miles (12.2 million kilometers). Using archive data from telescopes worldwide, a team of astronomers, including Mahadevan, was able to refine the accuracy of the radial velocity measurements for planet GJ 251b

The team then combined this refined data with brand new, high-precision observations from the Habitable-Zone Planet Finder (HPF), which is a near-infrared spectrograph on the Hobby-Eberly Telescope at McDonald Observatory in Texas. This revealed a second planetary signal belonging to a four-Earth-mass world orbiting the star every 54 days. That was then confirmed by measurements with the NEID spectrograph on the 3.5-meter WIYN telescope at Kitt Peak National Observatory in Arizona.

Though it may sound straightforward, in reality, the challenge of detecting the planet was formidable.

Stars are constantly roiling and churning as convective bubbles burst through to their visible surfaces and prominences splutter into space. This creates a noisy background of what's called asteroseismic activity that manifests as Doppler shifted lines in the star's spectrum. Picking out the Doppler shifted radial velocity signals from this noise is tricky, requiring a great deal of modeling what a planetary signal should look like.

"This is a hard game in terms of trying to beat down stellar activity as well as measuring its subtle signals, teasing out slight signals from what is essentially this frothing, magnetospheric cauldron of a star-surface," said Mahadevan.

Now that we know about the planet, astronomers can plan future observations.

GJ 251c is probably a little bit too far away from its star for the James Webb Space Telescope (JWST) to search for signs of an atmosphere around it. The next generation of 30-meter-class telescopes might be able to detect the planet's atmosphere via a method of searching for light reflected off its surface or atmosphere, but it will likely require the Habitable Worlds Observatory, which is a planned giant space telescope that is hoped to launch in the 2040s, to fully characterize GJ 251c.

"We are at the cutting edge of technology and analysis with this system," said Corey Beard of the University of California, Irvine, who participated in the research. "We need the next generation of telescopes to directly image this candidate."

Although GJ 251c is described by Mahadevan as being "one of the best candidates in the search for an atmospheric signature of life," referencing how we will search for biosignatures in the planet's atmosphere, there remains an elephant in the room: its star.

At 36% of the mass of our sun, the star GJ 251 is a red dwarf. Astronomers have now found numerous rocky planets in the habitable zone of red dwarfs, including Proxima Centauri b, TRAPPIST-1e and f, and Teegarden's Star b. However, red dwarfs are notorious for having violent tempers that bely their diminutive stature, releasing regular powerful flares that can over time strip a planet of its atmosphere. For example, the JWST's observations of the inner three planets of TRAPPIST-1 find no evidence for an atmosphere, while its observations of the fourth planet, e, are so far inconclusive. Some astronomers are now growing skeptical that Earth-like worlds can thrive around red dwarfs.

What GJ 251c has going for it is that it is slightly farther away from its star than habitable zone planets found around other red dwarfs are. This is thanks to its star being a little more massive than those other stars and therefore hotter, pushing the habitable zone farther out. It is possible that GJ 251c is far enough away from its star to have avoided the worst of its temper tantrums, and, if armed with a thick atmosphere and strong planetary magnetic field, it could have resisted the star's stellar wind from stripping its atmosphere away.

However, at present, this remains guesswork. "We made an exciting discovery," said Mahadevan, "But there’s still much more to learn about this planet."

The findings were reported on Oct. 23 in The Astronomical Journal.

The photo, shared by NOAA's Space Weather Prediction Center on X, shows our planet silhouetted by the solar corona.

What is it?

The image was taken by GOES-19, the newest in the Geostationary Operational Environmental Satellite series operated by NOAA. Launched in 2024 and declared operational in early 2025, GOES-19 continuously monitors Earth's weather and the turbulent space environment surrounding it.

Where is it?

GOES-19 sits around 22,000 miles (36,000 kilometers) above Earth's equator, in geostationary orbit. At this altitude, orbital speed matches Earth's rotational speed, allowing satellites to "hover" over patches of the planet.

Why is it amazing?

Among the instruments GOES-19 uses is CCOR-1, short for Compact Coronagraph 1, an experiment designed to capture real-time images of the sun's outer atmosphere, known as the corona. Normally invisible to the human eye, the corona glows faintly in visible light and extends millions of miles into space. It is from this region that coronal mass ejections (CMEs), vast bursts of plasma and magnetic field, erupt into the solar system, sometimes striking Earth and disturbing satellites, power grids and communication networks.

Though this image may look like a space selfie gone wrong, it shows that CCOR-1 is working as designed; it's sensitive enough to capture faint solar structures even when an object as bright as Earth enters its view. Earth's photobomb also provides a useful calibration test, helping scientists understand how CCOR-1 handles stray light, reflections and the brightness contrast between celestial objects.

Want to learn more?

You can learn more about coronagraphs and weather satellites.

After the Gemini North Telescope in Hawaii imaged a faint potential companion to Betelgeuse, Carnegie Mellon University (CMU) researchers used NASA’s Chandra X-ray Observatory and the Hubble Space Telescope to examine Betelgeuse in more detail. And the timing was perfect — Betelbuddy, as the tiny companion is nicknamed — was at its maximum distance from its much larger, much brighter neighbor. (Betelgeuse is about 700 times the size of our sun and thousands of times brighter.) Finally, researchers made detailed, concrete observations.

"It turns out that there had never been a good observation where Betelbuddy wasn't behind Betelgeuse," Anna O’Grady, a postdoctoral fellow at CMU,"said in a statement. "This represents the deepest X-ray observations of Betelgeuse to date.”

Impressively, capturing an image of Betelbuddy was only the start of the discoveries. The researchers had anticipated the companion to be a white dwarf or a neutron star, but they saw no signs of accretion, a distinct signature of both types of objects. Instead, they suspect it might be a young stellar object about the size of our sun.

And herein lies the next major discovery. The size ratio between Betelgeuse and Betelbuddy challenges what we currently know about binary stars. Typically, binary stars have similar masses. But Betelgeuse is about 16 to 17 times the mass of our sun, whereas Betelbuddy has about the same mass as our sun.

"This opens up a new regime of extreme mass ratio binaries,” O’Grady said. "It's an area that hasn’t been explored much because it's so difficult to find them or to even identify them like we were able to do with Betelgeuse."

This is only the start of the tale of Betelgeuse and Betelbuddy, and we can't wait to see where it takes us next.

The team's research will be published in The Astrophysical Journal on Oct. 10.

What is it?

In a recent image released by the European Space Agency, the Copernicus Sentinel-2 satellite captured an image of Chile's Laguna San Rafael National Park. Spanning approximately 10,500 square miles (17,000 square km), the park lies along Chile's Pacific coast and in the Patagonian region. Its ice fields feed into 28 outlet glaciers, including the two largest glaciers seen in the image: San Rafael and San Quintin.

Where is it?

The Copernicus Sentinel-2 satellite is located around 477 miles (768 km) above Earth.

Why is it amazing?

Along with this recently taken image, the European Space Agency produced a similar image for comparison, taken in February 1987. Looking at the two satellite images, it's easy to see the retreat of the glaciers over time, as the Earth's climate continues to change.

The glaciers' retreats have changed the landscape significantly, widening lakes and producing new bodies of water, proglacial lakes, a growing pool of meltwater. Simultaneously, their shrinking contributes directly to rising sea levels, one of the most profound and far-reaching consequences of climate change.

Want to learn more?

You can learn more about glacier melting and global warming.

Previous research has found that the surface of Mars is rich in ice. Most of these deposits are located at its poles, just as seen on Earth. However, recently the Mars Odyssey and the ExoMars Trace Gas Orbiter spacecraft detected elevated levels of hydrogen near the ground on the equatorial regions of Mars. This ice could have lasted for long spans of time if buried under dust or volcanic debris, and still might exist below the surface of equatorial regions on the Red Planet.

Scientists are now wondering how this ice might have originated in this unexpected area. Prior work noted one possible origin of this ice was volcanism, which could disgorge large amounts of water vapor.

Using computer models of the Martian climate, researchers simulated explosive volcanic eruptions that previous research found happened on the Red Planet between 4.1 billion and 3 billion years ago. The models suggested that the eruptions released water vapor into high altitudes, which could have frozen in the cold Martian atmosphere and later fallen as ice. Just one single three-day eruption could have resulted in ice deposits up to 16 feet (5 meters) thick in the area right around a volcano, they found.

"Imagine how much ice could be delivered after repeated eruptions over the course of millions of years," study lead author Saira Hamid, a planetary scientist at Arizona State University in Tempe, told Space.com. "Explosive volcanism could repeatedly seed low latitudes with ice and ash, producing buried or insulated ice deposits that help explain the excess hydrogen signals measured near the equator."

Hamid cautioned that the hydrogen that spacecraft have detected around the Martian equator might not come from deposits of ice, but a range of minerals, among other possibilities. Future research can look for signs of ash-covered ice in the equatorial regions of Mars to support or refute the chances of ice there, she noted.

If these equatorial ice pockets exist on Mars, they could prove valuable for human explorers there. "Our work suggests volcanic regions may be high-priority targets," Hamid noted.

In addition, volcanic eruptions could have spewed out sulfuric acid into the Martian atmosphere. This could have generated sunlight-reflecting aerosols that cooled the Red Planet, plunging it into a global winter that could in turn have let ice accumulate for a prolonged time.

But these ancient Martian volcanic eruptions might have also generated heat and chemicals "that could create short-lived habitable environments," Hamid said. "Those regions might have offered transient but potentially life-supporting conditions. Understanding where and how these ice–ash deposits formed could help guide the search for past or even preserved biosignatures on Mars."

The scientists detailed their findings October 14 in the journal Nature Communications.

That's the new prediction from two European researchers whose computer code allows them to identify when spacecraft can align with a comet's tail and the sun. Completely harmless to the spacecraft, the event provides a rare and fortuitous alignment — and a unique opportunity to directly sample material from a comet from beyond our region of the cosmos.

"We have virtually no data on the interior of interstellar comets and the star systems that formed them," Samuel Grant of the Finnish Meteorological Institute, who led the research, told Space.com. "Sampling the tail in this way is the closest we can currently get to a direct sample of such an object, and thus a different part of the galaxy."

Despite this huge opportunity, however, there are a number of things that could work against Europa Clipper detecting charged particles from 3I/ATLAS. For instance, the U.S. government shutdown persists. This is an issue because Europa Clipper is currently in cruise mode as it continues its journey to Jupiter and not all of its instruments are activated. The alignment between Europa Clipper, the comet and the sun falls into place between Oct. 30 and Nov. 6, and if the shutdown is not resolved by then, it's unclear whether scientists can awaken Europa Clipper to make the measurements even if they want to.

If the measurements can be made, though, they will provide insights into the composition of the interstellar comet, allowing comparisons with comets from our own solar system.

Comet anatomy

Comets possess two tails formed from particles and dust lifted off a comet's surface, or outgassed due to rising temperatures on the comet as it nears the sun. The heat causes pockets of gas just beneath the surface to expand and burst out.

A comet's dust tail is the most prominent and follows the trajectory of the comet. No spacecraft is currently in position to fly through 3I/ATLAS' dust tail and sample it.

The ion tail, however, is another matter.

"We study cometary bodies because they act as time capsules, sealing in material from their formation billions of years ago," said Grant. "This material is ejected on approach to the sun, a portion of which is transported away from the sun by the solar wind to form the ion tail."

Because it is driven by the solar wind, which is radiating out from the sun, the ion tail always points away from the sun.

Between Oct. 30 and Nov. 6, Europa Clipper will be in position to potentially receive some of those ions transported by the solar wind towards the spacecraft at several hundred miles per second.

Along with Grant, Geraint Jones — of the European Space Agency and principal investigator of the Comet Interceptor mission — was able to predict the ion tail crossing thanks to their Tailcatcher program, which is computer code that can track the movements of packets of solar wind material.

"We use the velocity measured at [a packet's] arrival to trace back the path it took to travel from the sun to the spacecraft, and we can compare this path to the position of the comet," said Grant.

Their calculations indicate that Europa Clipper could intercept some of the solar wind packets that came close enough to the comet to steal away some of the ions in its ion tail.

The solar wind carries ions of its own from the sun, so how can scientists differentiate between solar-wind ions and ions stolen from the comet?

"Cometary ions can be distinguished in a number of ways, most simply by chemical abundances — cometary ions include significant amounts of heavier species, particularly water-group ions, compared to the proton and helium-dominated solar wind," said Grant. "Additionally, the act of loading additional mass into the solar wind causes a general slowing and deflection of the ambient solar wind flow."

Probability of a particle shower

A successful detection also relies on properties intrinsic to the solar wind. First, the solar wind has to be flowing in the right direction; although it always flows from the sun, it is not always perfectly radial and sometimes it can flow at an angle, in which case it might miss Europa Clipper.

The wind also has to be strong enough at the right time to be able to carry the heavier ions all the way out to Europa Clipper. The comet is at perihelion — its closest point to the sun — on Oct. 29, when it will be at a distance of 126 million miles 200 million kilometers), inside the orbit of Mars. Meanwhile, Europa Clipper is currently over 186 million miles (300 million kilometers) from the sun having conducted a flyby of Mars earlier this year.

On the plus side, as 3I/ATLAS edges closer to the sun, activity on the comet will continue to ramp up. If this trend continues, then, at perihelion, the ion tail will be at its broadest, increasing the chances of Europa Clipper being able to detect some of its ions.

The European Space Agency's Hera spacecraft, on its way to the double asteroid system of Didymos and Dimorphos, will also be in a position to intercept solar wind packets carrying cometary ions between Oct. 25 and Nov. 1. However, Hera has no instruments for measuring the solar wind's charged particles and magnetic field. Europa Clipper does, since part of its mission is to study Jupiter's magnetic and radiation environment and its impact on Europa.

Yet, neither Grant nor Jones are members of the Europa Clipper team, and therefore have no say on how or whether the team makes the measurements.

But even if Europa Clipper misses out this time, Tailcatcher has been used to successfully predict ion tail crossings before, such as when the European Space Agency's Solar Orbiter spacecraft detected ions from the comet C/2019 Y4 in 2020. Its history of successful predictions means that it will undoubtedly be able to identify tail crossings in the future — perhaps even for the next interstellar comet, whenever that might turn up.

Indeed, the possibility of tail crossings adds an extra dimension to studying comets. In 2029, the European Space Agency will launch the Comet Interceptor mission, which will hold station in space until scientists identify a comet worthy of being visited by the spacecraft. Interstellar comets are high on the list.

"Comet Interceptor's primary objective is to fly close enough to an interstellar or long-period comet as to directly sample the coma and head of the tail," said Grant, who is not a member of the Interceptor team. "It would be an amazing opportunity if another spacecraft was able to cross upstream of the tail at a similar time."

Grant and Jones' prediction of the ion tail crossing is reported in a pre-print posted to the arxiv pre-print paper repository.

Experiments at NASA's Jet Propulsion Laboratory (JPL) in Southern California, coupled with computer simulations performed by researchers at the Chalmers University of Technology in Sweden, have shown how molecules of liquid ethane and methane, which fill the seas and lakes on Titan, can mix with crystals of hydrogen cyanide, which is frozen in the moon's frigid minus 179 degrees Celsius temperature.

Hydrogen cyanide is what's described as a polar molecule, in the sense that it has one side with a positive electric charge and another side that is negative. This means that it prefers to link up with other polar molecules, with opposite charges attracting.

On the other hand, methane and ethane, which are both hydrocarbon compounds (i.e. they are formed of atoms of hydrogen and carbon) are non-polar molecules, meaning that their electric charge is symmetrical, with both positive and negative charges on each side of their molecular structure.

Ordinarily, polar and non-polar substances don't mix. It's a little like oil remaining separate from water.

Hydrogen cyanide is formed in Titan's atmosphere via reactions with ultraviolet light from the sun, which breaks down hydrocarbons and reforms them as other molecules. Given that non-polar hydrocarbons are common throughout Titan's atmosphere and surface, scientists at JPL wanted to know what happens to the hydrogen cyanide after its creation. Yet their laboratory experiments mixing hydrogen cyanide with methane and ethane, performed at a temperature of minus 292 degrees Fahrenheit (minus 180 degrees Celsius), produced some surprising results that they didn't understand. So they approached chemist Martin Rahm and his group at Chalmers, who had prior expertise with hydrogen cyanide at cold temperatures, in their search for answers.

"This led to an exciting theoretical and experimental collaboration between Chalmers and NASA," said Rahm in a statement. "The question we asked ourselves was a bit crazy: Can the measurements be explained by a crystal structure in which methane or ethane is mixed with hydrogen cyanide? This contradicts a rule in chemistry, 'like dissolves like,' which basically means that it should not be possible to combine these polar and non-polar substances."

Rahm's computer simulations found that methane and ethane can penetrate into frozen hydrogen cyanide's crystal lattice, forming a new and stable structure called a "co-crystal."

"This can happen at very low temperatures, like those on Titan," said Rahm. "Our calculations predicted not only that the unexpected mixtures are stable under Titan's conditions, but also spectra of light that coincide well with NASA's measurements."

Titan is the only moon in the solar system to possess a thick atmosphere, and its hydrocarbon chemistry is similar to the prebiotic soup that scientists think existed on Earth before life began. Although the cold temperatures on Titan seem to preclude the kinds of chemical reactions that could lead to life as we know it, Titan's astrobiological worth is as a starting point, presenting what the molecular inventory might have been like on early Earth. Despite its toxicity to life now, hydrogen cyanide in particular is one of the building blocks of amino acids, which are used to construct proteins, and nucleobases in RNA and DNA.

"Hydrogen cyanide is found in many places in the universe, for example in large dust clouds, in planetary atmospheres and in comets," said Rahm. "The findings of our study may help us understand what happens in other cold environments in space. And we may be able to find out if other non-polar molecules can also enter the hydrogen cyanide crystals and, if so, what this might mean for the chemistry preceding the emergence of life."

Either way, the findings suggest even closer interactions between Titan's atmosphere, its frozen surface of ice dunes, and its lakes and seas of methane and ethane, than anyone had anticipated. When it arrives at Titan in 2034, NASA's new rotorcraft, called Dragonfly, will be making stops on the surface and sampling materials, including hydrogen cyanide ice, where it will be able to verify the new results and look for even more complex and unexpected chemistry.

The findings were published in July in the journal PNAS.

The study, published Tuesday (Oct. 14) in the journal Nature Geoscience, suggests that tiny chemical clues of this proto-Earth have survived deep within Earth's rocks, essentially unaltered, for billions of years. The findings provide a rare window into the planet's original building blocks and could offer scientists clues about what Earth and its neighboring worlds were like in their earliest eras.

"This is maybe the first direct evidence that we've preserved the proto-Earth materials," Nicole Nie, an assistant professor of Earth and planetary sciences at MIT who co-led the new paper, said in a statement.

Roughly 4.5 billion years ago, the young solar system was a swirling cloud of gas and dust that formed the first asteroids and planets, including the young Earth, then a hot, molten sphere likely bubbling with oceans of lava.

Less than 100 million years later, a Mars-sized asteroid collided with the proto-Earth in an event so violent it melted and remixed nearly the entire planet, creating the moon in the process. It was the last event to cause large-scale melting of Earth's mantle, the new study notes, and scientists have long suspected that this "giant impact" wiped away nearly all chemical traces of what came before.

But Nie and her colleagues uncovered a subtle imbalance in potassium isotopes in ancient rock, specifically a deficit of potassium-40. This anomaly, the researchers argue, is a potential fingerprint of material that survived from the proto-Earth itself.

"We see a piece of the very ancient Earth, even before the giant impact," Nie said in the statement. "This is amazing because we would expect this very early signature to be slowly erased through Earth's evolution."

Potassium occurs naturally in three isotopes — potassium-39, potassium-40 and potassium-41, which are slightly different versions of the same element with varying numbers of neutrons but the same number of protons.

In 2023, Nie's team analyzed meteorites that formed at different times and locations across the solar system that had been collected from around Earth. The researchers found subtle potassium isotopic differences among them, which meant that the different isotopes could "be used as a tracer of Earth's building blocks," Nie said in the statement.

In the new study, the team hunted for similar potassium anomalies in Earth's oldest and deepest rocks. These were samples collected from Greenland, Alexo in Canada's Abitibi belt and the Winnipegosis komatiite belt in Manitoba; Hawaii's Kama'ehuakanaloa and Mauna Loa volcanoes; and the Newberry volcano in the Cascade Range of the northwestern United States.

"If this potassium signature is preserved, we would want to look for it in deep time and deep Earth," Nie said in the statement.

The researchers found that these ancient materials contained even less potassium-40 than expected, suggesting that the rocks "were built different," Nie said in the statement.

To detect such a minute signal, the researchers dissolved the powdered rocks in acid, isolated the resulting potassium, and then used an ultra-sensitive mass spectrometer to precisely measure the ratios of the element's three isotopes, according to the new study.

The researchers also ran computer simulations to test whether known geological or cosmic processes, such as asteroid impacts, convection of materials from Earth's mantle to its surface, or large-scale planetary melting could explain the potassium isotope ratios they observed. But in every scenario that was modeled, the simulated compositions contained slightly more potassium-40 than what the actual rock samples from Canada, Greenland and Hawaii contained.

This deficit represents the primitive proto-Earth mantle that largely escaped the mixing caused by the giant impact and still exists deep within Earth today, the researchers say.

While meteorites studied in the team's earlier work also showed potassium anomalies, they did not exhibit the exact same deficit, suggesting that the materials that originally formed the proto-Earth have yet to be discovered.

"Scientists have been trying to understand Earth's original chemical composition by combining the compositions of different groups of meteorites," Nie said in the same statement.

"But our study shows that the current meteorite inventory is not complete, and there is much more to learn about where our planet came from."

What is it?

Orbiting above Earth's atmosphere, Hubble observes galaxies like NGC 6951 in visible and infrared light, capturing details that ground-based telescopes cannot. Its images have illuminated how galaxies form, evolve and recycle their material through generations of star birth and death.

In Hubble's recent image, NGC 6951 unfurls its graceful spiral arms, covered in red nebulae glowing with hydrogen gas, a key fuel for new stars.

Where is it?

The spiral galaxy NGC 6951 is located 70 million light-years from Earth, in the constellation Cepheus.

Why is it amazing?

Crossing the core of NGC 6951 is a bar of stars, a common feature in elongated spiral galaxies that acts as a kind of galactic conveyor belt, channeling gas inward toward the nucleus. That flow of gas gives rise to one of the galaxy's most captivating features: a circumnuclear starburst ring about 3,800 light years wide that encircles the galactic heart.

Within this ring, the conditions are just right for an intense burst of star formation. The bar funnels cold gas to the central region, where it collects and compresses, triggering the birth of new stars at a significant rate. Using Hubble's data, astronomers have identified more than 80 possible star clusters inside this ring, many less than 100 million years old, though the spiral galaxy itself has likely persisted for over a billion years.

Want to learn more?

You can learn more about the Hubble Telescope and the process of stellar evolution.

Update for Oct. 21: Due to cloudy weather, this livestream was rescheduled for Oct. 24, beginning at 1:30 p.m. EDT (1730 GMT).

Two comets, C/2025 A4 (Lemmon) and C/2025 R2 (SWAN), are about to reach their closest approach to Earth and you can watch the action unfold live online.

Astronomer Gianluca Masi and his Virtual Telescope Project will host a special livestream on Oct. 24 beginning at 1:30 p.m. EDT (1730 GMT) to watch as both comets make a close pass to Earth, making them well placed for observations.

"So far, living in the Northern hemisphere, I could admire C/2025 A6 Lemmon only,
but C/2025 R2 SWAN is quickly joining the show and we are ready to amaze every
astronomy lover with our live feed!" Masi told Space.com in an email.

You can watch the cosmic show live here on Space.com courtesy of the Virtual Telescope Project or on the project's website or YouTube channel, weather permitting.

Rare double-comet encounter

Having two right comets visible in the sky around the same time is a rare cosmic treat. During the event, Comet Lemmon (C/2025 A6) will pass about 56 million miles (90 million kilometers) from Earth, while Comet Swan (C/2025 R2) will soar even closer, at roughly 24 million miles (39 million km). Both are expected to peak in brightness between Oct. 20 and Oct. 21.

Comet C/2025 A6 (Lemmon) was discovered in January 2025 and has been steadily brightening as it soars through the inner solar system. Lemmon is visible in a pair of binoculars or small telescopes in the western evening sky after sunset, slowly climbing higher each night as it moves northward.

Comet C/2025 R2 (SWAN) was discovered in September 2025 by the Solar and Heliospheric Observatory's SWAN instrument. It is best viewed in the predawn sky, when the comet appears low on the eastern horizon as it continues its journey away from the sun.

If you're hoping to spot the comets yourself, check out our guides to the best binoculars and best telescopes for beginners, as well as our how to photograph comets guide. And don't forget to explore our night sky guide for more celestial highlights this month.

Editor's note: If you capture a photo of Comet Lemmon or Comet SWAN and would like to share it with Space.com, send your images and comments to spacephotos@space.com.

A new study from NASA and Penn State University suggests fragments of biomolecules from ancient microbes could survive in Martian ice for tens of millions of years — long enough for future missions to potentially find them, according to a statement from the university.

In laboratory experiments simulating Mars conditions, researchers froze samples of E. coli bacteria in two different environments: pure water ice and a mixture of water and ingredients found in Martian soil, including silicate-based rocks and clay. The samples were cooled to minus 60 degrees Fahrenheit (minus 51.1 degrees Celsius) — the temperature of icy regions on Mars — and then exposed to radiation levels equivalent to what they would experience over 20 million years on Mars. The results were extended through modeling to represent 50 million years of exposure, according to the statement.

"Fifty million years is far greater than the expected age for some current surface ice deposits on Mars, which are often less than two million years old, meaning any organic life present within the ice would be preserved," Christopher House, co-author of the study and professor of geosciences, said in the statement. "That means if there are bacteria near the surface of Mars, future missions can find it."

The researchers found that the amino acids — the building blocks of proteins — survived far better in pure ice than in ice mixed with sediment. More than 10% of the original amino acids remained intact after the simulated 50-million-year exposure, while those in the soil mixture degraded 10 times faster and did not survive. When tested under even colder temperatures similar to those on Europa, an icy moon of Jupiter, and Enceladus, an icy moon of Saturn, the researchers found it further reduced the rate of deterioration.

Therefore, the researchers suggest that in pure ice, radiation byproducts such as free radicals become trapped and immobilized, slowing the chemical breakdown of biological molecules. In contrast, the minerals in Martian soil appear to create thin films of liquid that allow destructive particles to move and cause more damage.

"These results suggest that pure ice or ice-dominated regions are an ideal place to look for recent biological material on Mars," Alexander Pavlov, lead author and a space scientist at NASA Goddard Space Flight Center, said in the statement.

This can help better plan which areas to target during future Mars missions and how to design tools capable of drilling into subsurface ice deposits — most of which are believed to be less than two million years old, meaning any biomolecular traces from a more recent habitable period could be preserved in the frozen ice.

Their findings were published Sept. 12 in the journal Astrobiology.

Scientists spotted the heavy water (which we'll get into in just a moment) in the planet-forming disk of gas and dust around the young star V883 Orionis by ALMA, the Atacama Large Millimeter/submillimeter Array, which is a network of 66 radio dishes in Chile. V883 Ori is located 1,350 light-years away and is a member of a cluster of stars born out of the famous Orion Nebula.

Now, here's what heavy water is.

Ordinary water is formed of two atoms of hydrogen and one atom of oxygen. Hydrogen is made from a single proton orbited by an electron. However, the nuclei of some atoms of hydrogen feature one proton and one neutron, too. We describe atoms with extra neutrons as an isotope of that element, and the isotope of hydrogen with one neutron is called deuterium. Its atomic mass is slightly higher than regular hydrogen, thanks to that extra neutron.

Heavy water, therefore, supplants its two regular hydrogen atoms with two deuterium atoms. We have heavy water in our own solar system, found for example in comets — and the ratio of heavy water to ordinary water in a cometary body can tell us about its formation history.

"Until now, we weren't sure if most of the water in comets and planets formed fresh in young disks like V8783 Ori, or if it is pristine, originating from ancient interstellar clouds," said John Tobin of the National Radio Astronomy Observatory in the United States in a statement.

The ALMA observations provided the answer. Violent shocks and outbursts from young stars destroys heavy water in a planet-forming disk, allowing it to reform as regular water. If this had happened around V883 Ori, the ratio of heavy water to regular water would be low, similar to what we find in our solar system.

Instead, however, the ratio as measured by ALMA in V883 Ori's disk is the same as what is observed in clumps of molecular gas before they have formed stars or planets. In fact, the ratio is two orders of magnitude higher than what it would be if the water had been broken apart and reformed in the disk.

"Our detection indisputably demonstrates that the water seen in this planet-forming disk must be older than the central star and formed at the earliest stages of star- and planet-formation," said Margot Leemker, of the University of Milan, who led the study. "This presents a major breakthrough in understanding the journey of water through planet formation, and how this water made its way to our solar system and possibly Earth, through similar processes."

This means the water is older than the star — it could actually be billions of years older, having sat in the molecular cloud that became the Orion Nebula all that time as ice coating tiny dust grains.

V883 Ori is only half a million years old, and water was first detected in its circumstellar planet-forming disk in 2023. No planets have yet been detected in that disk, although any comets that may have formed already will mirror this high ratio of heavy water. The star's young age means there hasn’t been enough time yet for its ancient water to have been reprocessed by heating in the disk, but that time will soon come, as outbursts from the young star have already been observed — for example, in 2016, when ALMA studied the outburst's effect on the snow line, or where water turns from vapor to ice, in V883 Ori’s disk.

"The detection of heavy water … proves the water's ancient heritage and provides a missing link between clouds, disks, comets and ultimately planets," said Tobin. "This finding is the first direct evidence of water’s interstellar journey from clouds to the materials that form planetary systems — unchanged and intact."

The results were published on Oct. 15 in the journal Nature Astronomy.

The Mauve telescope, developed by London-headquartered start-up Blue Skies Space, is the size of a small suitcase and carries an off-the-shelf ultraviolet spectrometer modified to monitor flaring stars. It is one of the payloads that will launch on SpaceX's upcoming Transporter-15 mission, currently set for no earlier than November 2025.

Just like our sun, other stars in the universe produce flares — flashes of high-energy radiation from the dark, magnetically dense regions known as sunspots. Each flare sends a wave of energetic particles into the star's surroundings. When such a wave washes over Earth, the radiation, consisting of X-ray and extreme ultraviolet light, interferes with radio transmissions, causing blackouts. The flare also disturbs the ionosphere — the electrically charged layer of Earth's atmosphere at altitudes above 20 miles. This interference affects the accuracy of the navigation and positioning signal from satellites such as the U.S. GPS system.

But the sun is not a very active star. Research suggests that many of its siblings are much more temperamental. The bursts of radiation that some stars produce are so intense and so frequent that they virtually sear any object in their vicinity, preventing any possible life from emerging. By tracking the flaring of hundreds of stars, Mauve will help astronomers pick out those that are more likely to host habitable exoplanets.

"Mauve will allow us to understand the behavior of stars when they are emitting large amounts of energy," Marcell Tessenyi, the founder and CEO of Blue Skies Space, told Space.com. "It will also help us understand what sort of impacts these stars might have on their neighboring planets. We will be able to understand which stars are likely to be damaging for a life environment and which would be benign."

The last dedicated mission to observe stellar ultraviolet light, the International Ultraviolet Explorer, ended in 1996. The legendary Hubble Space Telescope can perform such measurements, but availability of observing time is limited, Tessenyi said. Hundreds of science teams from all over the world compete for observing time on the veteran space telescope, pursuing a multitude of challenging astronomical research projects that can't be accomplished by any other star-watching machine.

Since scientific interest in exoplanets is on the rise, Blue Skies Space decided to cover the increasing demand for observations of stellar flares with a small, low-cost telescope and sell the resulting data to scientists worldwide through a yearly subscription model.

"The space agencies do a fantastic job at delivering very high-quality space telescopes, but sometimes it can take a long time," Tessenyi said. "And when these satellites are operational, like the Hubble Space Telescope or James Webb, people have to apply and hope they get the observing time they need. But not all science requires a very large and complicated satellite."

With the low-cost Mauve (the company refused to disclose the exact cost of the mission), Blue Skies Space is pioneering a new approach to astronomical research from space. Although the new commercial space ethos of building satellites fast and cheap has dominated Earth imaging from space for years, deep-space astronomy has so far been headed mostly in the opposite direction — trending toward more complex machines worth billions of dollars.

Mauve, built in less than three years, is Blue Skies Space's first satellite to launch, although it was conceived after another mission, called Twinkle, which is still in the works. Twinkle, expected to make it to space later this decade, is a larger satellite, weighing 330 pounds (150 kilograms in mass) and carrying an 18-inch (45 cm) telescope. Like Mauve, Twinkle will look for exoplanets around nearby stars and gather information about their chemical composition. But Mauve, Tessenyi said, will help the researchers zoom in on the most promising stellar systems, to make Twinkle's work easier.

Tessenyi said that despite initial scepticism among scientists whether the new space way could work for astronomy, Blue Skies Space has seen a lot of interest in both of their missions. Nineteen universities from all over the world have already signed up for the data, which will begin streaming to Earth early next year.

Mauve will orbit Earth at an altitude of 310 miles (500 kilometers) for at least three years. If the project is successful, Blue Skies Space might add more satellites to its fleet in the future. The company is already studying a concept of a successor to Mauve, a more potent UV-observer Mauve+.

"We finance the satellites upfront, put them into space, and once the mission is operational, we make data available to users and over time we recover the cost of the construction and operations," Tessenyi said. "If the satellite is a success and we make a surplus, we reinvest that into our subsequent satellites and we grow the company to deliver more satellites using this model."

Its twin, Gemini South, is located in the Atacama Desert in Chile. Together, these telescopes form a powerful duo that allows astronomers to observe the entire sky from both hemispheres.

What is it?

In this long-exposure image, the lines of light in the night sky are caused by both stars and satellites moving across the heavens. Satellite streaks in particular are becoming a growing issue for telescopes like Gemini North and Gemini South, as they can affect the accuracy of measurements.

Where is it?

The Gemini North telescope is located on top of Mauna Kea in Hawaii.

Why is it amazing?

In recent years, the growing number of satellites in orbit has increased dramatically as private companies like SpaceX and Amazon launch large satellite constellations to deliver global broadband internet and other services. While these networks bring important technological advances, their presence also means more bright objects moving in the sky.

For observatories like Gemini North and Gemini South, this poses a serious issue. The reflected light from satellites can contaminate astronomical images, obscuring faint celestial objects or creating unwanted artifacts in valuable data. These disruptions make it harder to study phenomena like distant galaxies, near-Earth asteroids and the subtle signatures of exoplanet atmospheres.

To help mitigate this problem, the U.S. National Science Foundation's NOIRLab, which helps run both Gemini North and Gemini South, co-hosts the Center for the Protection of the Dark and Quiet Sky (CPS), a global collaboration that coordinates research and advocacy efforts to preserve our natural view of the cosmos.

Want to learn more?

You can learn more about satellite pollution and working to protect dark skies.

Planetary scientists have long puzzled over strange, sinuous trenches etched into desert dunes on the Red Planet. The channels look freshly dug, complete with raised rims and winding paths, yet Mars today is too cold, too dry and too lifeless for running water — or giant worms — to be the cause.

Instead, a new study suggests that the gullies are sculpted by slabs of dry ice that form during the Martian winter. As spring approaches and temperatures warm, the sand heats up and blocks of ice break off, sliding and sublimating their way through the Martian sand, according to a statement from Utrecht University.

Inside a Mars simulation chamber, researchers placed carbon dioxide (CO2) ice blocks atop small sand dunes under low pressure and frigid temperatures to mimic the Red Planet's environment. As the ice warmed, it began to sublimate, turning directly from solid to gas. Gas trapped beneath the block built pressure until it vented explosively, lifting and propelling the ice downslope. As it glided, the block plowed a narrow trench and pushed sand aside into small levees — forming miniature versions of the gullies seen across Mars from orbit.

"It felt like I was watching the sandworms in the film 'Dune,'"Lonneke Roelofs, lead author of the study and an Earth Scientist from Utrecht University, said in the statement. "In our simulation, I saw how this high gas pressure blasts away the sand around the block in all directions."

The study helps rule out other possible sources behind these gullies, such as liquid water, which would have implications for potential Martian habitability. Instead, the dry-ice process offers a purely physical, water-free explanation — proof that Mars can still reshape itself today, even without rivers or rainfall. Studying the formation of structures on other planets also offers new insight for understanding Earth's landscape by looking at underlying processes through a different lens, the researchers said.

"We tried out various things by simulating a dune slope at different angles of steepness. We let a block of CO2 ice fall from the top of the slope and observed what happened”, Simone Visschers, co-author of the study and master student at Utrecht University, said in the statement. "After finding the right slope, we finally saw results. The CO2 ice block began to dig into the slope and move downwards just like a burrowing mole or the sandworms from 'Dune.' It looked very strange!"

While no sandworms roam the Martian deserts, its dunes may indeed come alive each spring — when slabs of dry ice briefly tunnel through the sand and etch new gullies across the planet's surface.

Their findings were published on Oct. 8 in the journal Geophysical Research Letters.

When a star becomes caught in the vice-like gravitational grip of a massive black hole, tidal forces set about stretching and tearing the star apart. Such events, referred to as "tidal disruption events," or TDEs, are relatively common. They liberate a huge amount of energy as the star is ripped apart and its remains form a disk of debris around the black hole.

In this case, the optical flare of the TDE was spotted in 2024 by the Zwicky Transient Facility on the 48-inch Samuel Oschin Telescope at Palomar Observatory in California. Constant monitoring of the TDE, designated AT 2024tvd, at radio wavelengths over the next 10 months by an array of telescopes identified two distinct radio flares — for some reason, delayed by 80 and 194 days after the onset of the TDE respectively.

Even more surprising, however, was the location of the TDE: about 2,600 light years from the center of its host galaxy. Most TDEs take place in the center of a galaxy, where a supermassive black hole lurks.

Only three have ever been seen off-center.

"This is truly extraordinary," Itai Sfaradi of the University of California, Berkeley, said in a statement. "Never before have we seen such bright radio emission from a black hole tearing apart a star, away from a galaxy's center, and evolving this fast. It changes how we think about black holes and their behavior."

Sfaradi and his Berkeley colleague, Raffaella Margutti, led an international team to track the development of the TDE using the Very Large Array in New Mexico, the Allen Telescope Array in California and the Submillimeter Array in Hawaii, as well as the Atacama Large Millimeter/submillimetre Array (ALMA) in Chile and the Arcminute Microkelvin Imager Large Array (AMI-LA) at Cambridge University’s Mullard Radio Astronomy Observatory.

It was AMI-LA that was key to capturing the surprisingly fast development of the radio emission — fast in the sense that its energy rose and changed quickly. These radio waves are produced when an outflow of material slams into gas that surrounds the black hole. This gas could be the ordinary interstellar medium, or debris from the destroyed star.

Why these outflows were so delayed following the TDE remains a mystery. The first radio flare also came with a detected X-ray component, leading Sfaradi’s team to suspect that this outflow was accretion-driven: in other words, some of the debris in the accretion disk flowing onto the black hole was spat back out by the black hole's magnetic fields.

The second flare is even more puzzling.

Either it was a jet of material moving at half the speed of light that was launched 170 days after the TDE and took 24 days to reach the surrounding gas, or a jet moving at almost the speed of light that was launched after 190 days. What connection this second outburst has with the first, and whether it was produced by the accretion of the same material, remains unclear.

As for the black hole, Sfaradi's best guess is that it is an intermediate mass black hole — that is, a black hole with a mass between 1,000 and 100,000 times the mass of our sun. It could have found itself outside of the galaxy's center in one of two ways. Either it was a participant in a triple black hole interaction at the center of its galaxy that saw it thrown out, or it was once the central black hole of a smaller galaxy that collided and merged with a larger one, and the black hole is now wandering like a violent rogue through its new galaxy, obliterating any unfortunate stars that get in its way.

The results were published on Oct. 13 in The Astrophysical Journal Letters.

What is it?

Launched in 2021 as part of a long legacy of Earth-observing satellites, Landsat 9 is a joint mission of NASA and the U.S. Geological Survey (USGS). The satellite is equipped with state-of-the-art sensors. It captures high-resolution images in both visible and infrared light, allowing scientists to track environmental changes across continents, from shrinking glaciers and shifting coastlines to urban expansion and desert dynamics.

In this image, Landsat 9 reveals the Mazartagh Ridge rising around 600 feet (180 meters) above the surrounding sands, acting as a natural barrier against the relentless winds that sweep China's Takla Makan Desert.

Where is it?

This photograph was taken from 438 miles (705 km) above Earth in Landsat 9's orbit.

Why is it amazing?

The Hotan River, a dark green thread flowing from north to south in this image, carries glacial meltwater deep into the desert until it merges with the Tarim River.

Despite flowing through one of the world's most arid regions, the Hotan feeds ribbons of vegetation sprouting around its banks. Beyond its ability to sustain life, the Hotan's sediments once contained nephrite jade in both white and green varieties, making the region a key stop along the historic Silk Road, where traders once exchanged jade, silk and stories of far-off lands.

Want to learn more?

You can learn more about waterways and images of Earth from space.