Comet C/2025 K1 — NOT interstellar 3I/Atlas — breaks up as it passes closest to the Sun

The broken apart nucleus of Comet 3I/Atlas
Click for original image.

CORRECTION: I originally posted this story thinking the comet imaged was the interstellar Comet 3I/Atlas. It is not. It is a different one. I have changed to post below to correct my error.

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Sometime on November 11, 2025, the nucleus of interstellar C/2025 K1 broke into three pieces as it passed through its closest and hottest point to the Sun.

The image to the right, cropped and reduced to post here, comes from images of the break-up taken by the Virtual Telescope project, which gathers data from many small telescopes remotely.

From the first link, translated by Google from the Italian:

Its trajectory led it, in early October, to pass through a point of minimum distance from the Sun (perihelion) quite close to our star, about 0.33 astronomical units, just outside the orbit of Mercury. Because of this “short” distance from the Sun, it experienced high solar irradiation, which caused a significant increase in the temperature of the surface and internal layers of the nucleus.

These are precisely the conditions under which a “breakup” event is expected: depending on the internal properties of the nucleus—namely, its porosity, its state of cohesion, its composition, and the percentage of ice—it is possible that the increase in temperature could cause significant “outgassing,” a sudden and violent outflow of gaseous and dusty material, and the consequent fragmentation of the nucleus, sometimes into a few pieces of roughly similar size, sometimes into a cloud of fragments and debris that spread along the trajectory of the original comet.

…”From an initial quick analysis of the images, we can confirm that there are certainly two fairly similar pieces, whose brightness maxima are separated by approximately 2,000 km (distance projected on the star field); “Furthermore, we can intuit the presence of a third, smaller and fainter fragment to the left of the pair,” observes Mazzotta Epifani.

It will be interesting to see if the same thing happens to interstellar Comet 3I/Atlas as it makes its own pass close to the Sun.

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Saturn’s rings, warped by one of Saturn’s moons

Daphne inside Saturn's rings
Click for original image.

Cool image time! Rather than post another Mars image, I decided today to dig into the archive left from the Cassini orbiter that circled Saturn from July 1, 2004 until September 15, 2017. The picture to the right, cropped to post here, was taken on September 13, 2017, only two days before the orbiter burned up in Saturn’s atmosphere. From the caption:

This image of Saturn’s outer A ring features the small moon Daphnis and the waves it raises in the edges of the Keeler Gap. The image was taken by NASA’s Cassini spacecraft on Sept. 13, 2017. It is among the last images Cassini sent back to Earth. The view was taken in visible light using the Cassini spacecraft wide-angle camera at a distance of 486,000 miles from Saturn. Image scale is 2.7 miles [per pixel].

The moon is traveling downward in this image. As it moves past the outer ring, its gravity causes that edge to ripple, producing the waves.

The scale will give you an idea of how big the rings of Saturn are. The Keeler Gap is at the outer edge of the A ring of Saturn, which is the outermost ring that is clearly visible using ordinary amateur telescopes. That edge however is more than 90,000 miles from Saturn. And grayish bands to the right of Daphne and the Keeler Gap are only the outer half of the A ring, which is by itself about 9,000 miles wide.

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The edge of Mars’ north polar ice cap

The fringe of Mars' perennial ice cap
Click for original image.

Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken on September 29, 2025 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).

The picture shows what the science team labels as a “fringe of perennial ice.” For this picture, north is down. The white stuff on the top half of the image is that perennial ice, while the dark material at the bottom is likely a mixture of dust and debris that is still impregnated with ice.

Mars is a very icy world. Orbital data now suggests that above 30 degrees latitude there is a lot of near surface ice, though it is often mixed in with the red planet’s ample dust, blown there for eons. This location however shows us a place where that ice is on the surface, and is generally pure.

That does not mean however this will be a good location to establish a colony.
» Read more

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Curiosity looks downhill at past travels

Curiosity looks downhill
Click for original image.

Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken on November 6, 2025 by the left navigation camera on the Mars rover Curiosity.

The picture looks north across Gale Crater, its distant rim about 20-30 miles away barely visible in the dusty atmosphere. In the foreground can be seen Curiosity’s recent tracks, showing how the science team had it travel back and forth several times, probably to check out several different interesting nearby ground features, as well as see how the ground changed by that travel. The rover has been traveling in an area called boxwork, a series of small intercutting ridges and hollows. Several of those ridges can be seen just beyond the tracks.

The red dotted line indicates my rough estimate as to the rover’s route uphill to get to this point, traveling up and to the left and following ridges just out of view.
» Read more

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Crazy layers inside a Martian crater

Crazy layers in a Martian Crater
Click for original image.

Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken on September 30, 2025 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).

The scientists label this image with the term “layers”, but to my eye this is kind of an understatement. The geology in the top half of this picture is more than simply layers, it is an example of that unique Martian geological feature dubbed “brain terrain”, but on steroids.

No one yet knows what causes brain terrain, though scientists think it is related to the sublimation of near surface ice. Normally the tubelike formations are much smaller, only ten to thirty feet long, not hundreds of feet as we see here.

In this case the location of these features makes their formation even more puzzling, as there is no near surface ice found here.
» Read more

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Webb tracks volcanic eruptions on Io

Different Webb infrared detections of Io over time
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Using the Webb Space Telescope, scientists have tracked two different volcanic eruptions on Io that too place from 2022 to 2023, detecting sulfur monoxide both from those eruptions as well as sulfur from the magnetic plasma torus produced as the planet travels through Jupiter’s strong magnetic field. From the paper’s abstract:

Volcanic thermal emission was detected from Loki Patera and Kanehekili Fluctus [two volcanic vents]. The main changes in the shape of the thermal emission spectra since [Webb] observed Io in November 2022 were consistent with the continued cooling of emplaced lava flows in the Kanehekili Fluctus region, and the crust that had formed on the surface of the lava lake in Loki Patera. Images of Io in the SO 1.707 μm emission band [sulfur monoxide] show a concentration above Kanehekili Fluctus and in two regions in the northern hemisphere. The emissions are sourced from SO molecules ejected from volcanic vents. We further detected, for the first time, sulfur line emissions at 1.08 and 1.13 μm. These emissions are distributed homogeneously across a band in Io’s northern hemisphere. They are mainly produced through excitation by electrons from the plasma torus, penetrating Io’s atmosphere.

The top image to the right shows the heat signature above the two volcanoes, one to the southwest and the second to the northeast. The middle image shows the sulfur monoxide emissions detected by Webb above those volcanoes from their on-going eruptions. The bottom image shows the more diffuse sulfur emissions, mostly in the northern hemisphere, believed produce by interactions with the plasma torus.

This research also relied on data obtained by both the Keck telescopes in Hawaii and the Hubble Space Telescope.

There are of course uncertainties with these results. For example, the conclusion that the more diffuse sulfur is produced by interactions with the plasma torus is not as certain. First, those sulfur emissions still appear closely linked to the volcanoes, which suggests this still could be a source.

Second, the observations also cover only two data points in time, in 2022 and 2023. To get a more precise map of the activity on Io we really need an orbiter there observing the planet on a continuous basis, something that is at this time impossible, not only because no mission is planned but because the hostile radiation environment this close to Jupiter makes the engineering quite challenging. It is this reason why Europa Clipper is not going into orbit around Europa when it arrives there in 2031. Better to orbit Jupiter and only periodically dip into that harsh radiation environment.

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This typical cliff on Mars just happens to match the walls of the Grand Canyon

A typical Martian cliff, comparable to the Grand Canyon
Click for original image.

Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken on August 23, 2025 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).

The label the science team gave this image, “remnant fan”, suggests the focus of research here is the fingerlike ridges on the floor of the canyon, emanating out from the cliff. These appear to be the remains of an ancient mass-wasting event, similar to an avalanche but different in that instead of it being a pile of surface material falling down the cliff, the cliff itself breaks free and slumps downward. In this case the event was so long ago that most of the slumped material has eroded away, leaving only those ridges, likely resistant to erosion because of the impact of the material from above.

If you look at the top of cliff, you can see evidence that another mass wasting event is pending. Note how the plateau floor near the cliff has dropped about 100 feet. This drop suggests that this part of the cliff has started to slump and break away from the plateau.
» Read more

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Someone is apparently considering putting a helicopter on Starship when it goes to Mars

Potential Starship helicopter location

In my regular trolling through the images sent down from Mars Reconnaissance Orbiter (MRO), I sometimes come across things that imply truly exciting future missions. That happened when in 2019 I found a bunch of photos each labeled as a “candidate landing site for SpaceX Starship”. Without fanfare SpaceX had begun researching locations for where it intended to land Starship on Mars, in the northern lowland plains, research that it later solidified considerably.

Similarly, I have found MRO images in 2022 suggesting scientists were thinking of running a helicopter mission inside Valles Marineris, the largest canyon in the solar system. Another image in 2024 suggested that a helicopter mission might go to another region in Mars’s southern cratered highlands.

The image to the right, cropped, reduced, and sharpened to post here, is another new example of a potential Martian helicopter mission. It was taken on August 19, 2025 and is labeled provocatively “Characterize Possible Rotorcraft Landing Site.” Unlike the previous two proposed helicopter locations, however — which appeared to be aimed at uncertain NASA funding — this image’s location suggests it is far more certain, and might launch far sooner than you can imagine.
» Read more

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ISS study suggests that weightlessness impacts the eyes of men more than women

Eye flattening while in space
Astronauts who experienced changes in their
eyes (SANS) while on long missions in space

The uncertainty of science: A recent study of 30 astronauts during long term stays on ISS suggests that weightlessness impacts the shape of the eyes more in men than in women.

You can read the paper here.

In addition to changes in fluid around the brain, the team also found that a form of eye compression, a hallmark of Spaceflight Associated Neuro-ocular Syndrome known as globe flattening, was the most consistent eye change among crew members. “By far the most prevalent sign of eye changes that we observed was globe flattening, suggesting that this should be the primary monitoring target for ocular health,” Seidler said. “Interestingly, eye changes were more prevalent in males than females.”

Globe flattening, when the back of the eyeball becomes slightly indented or pushed inward, might sound minor, but it can have significant effects on vision and raise concerns for long-duration space missions.

Surprisingly, there was no strong link between brain structural changes and eye changes, suggesting that the effects on the eyes and brain may arise from distinct mechanisms rather than shared physiological cause

For the eye research, the sample was so small, 28 individuals of which only 9 were females, the researchers readily admit in their abstract that and “interpretation of these findings should be tempered by the fact that our sample included a relatively small number of females.” Nonetheless, the research did suggest that, regardless of sex, about half of all humans will experience these eye issues during long missions in weightlessness.

The results underscore the need to do artificial gravity experiments in orbit, to find out the minimum amount of gravity needed to mitigate or even eliminate these health issues. Otherwise, interplanetary travel is going to be seriously hampered, if not impossible.

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New orbital radar data confirms large ice deposits in Phelgra Mountains near Starship landing zone

Overview map

A new paper published this week used the SHARAD radar instrument on Mars Reconnaissance Orbiter (MRO) to confirm that the glacial features found everywhere within the Phlegra Mountains where one of Starship’s four prime landing sites is located contains significant quantities of very accessible pure water ice.

The red dots on the map to the right mark two of those prime landing sites, with one inside the Phelgra Mountains in a region directly studied by this paper. The numbered black dots were other images taken by MRO for SpaceX, reported here in 2020. From the paper’s abstract:

We examined mid-latitude landforms on Mars that resemble Earth’s debris-covered glaciers in a region called Phlegra Montes. Our study site is a 1,400-km-long mountain range in the northern hemisphere of Mars that houses numerous debris-covered glaciers also called Viscous Flow Features (VFFs). Using data from the SHallow Radar (SHARAD) instrument, we detected eight new glaciers and estimated the thickness and volume of ice within them as well as the thickness of the debris on top insulating the ice. Our findings suggest that the region holds around 1.2 trillion cubic meters of ice below the surface. We detected two notable types of glaciers for the first time on Mars using SHARAD: (a) a glacier system with terrace-like steps and (b) a perched “hanging” glacier on the eastern side of the mountains

The study also found that the layer of dust and debris that covers these glaciers and protects them from sublimating away ranges from 6 to 25 feet in thickness, well within reach of any future colonists.

This study only confirms what all the orbital data for the past two decades has suggested, that Mars is an icy world like Antarctica, not a dry desert like the Sahara. As the researchers themselves note in the very first line of their paper, “Mars is a frozen world where water ice is abundant above, at, and under the surface.”

Their research also confirms that SpaceX has made a good choice for its Starship prime landing sites. Though it will likely not make its first landing at site #3, because it is inside the mountains and thus more risky, expect a landing there not long thereafter.

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The alien landscape of Mars’ north polar ice cap

The strange terrain of Mars' north polar ice cap
Click for original image.

Cool image time! The picture to the right, cropped to post here, was taken on August 24, 2025 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).

The camera team labels this simply as a “terrain sample,” which usually means it was not taken as part of any specific research request, but to fill a gap in the camera’s schedule in order to maintain its proper temperature. When they need to do this, they try to find interesting things to photograph, and mostly succeed.

At first glance the picture to the right does not appear that interesting. If anything it shows an endless expanse of mottled terrain, with no features of any interest at all. This sameness however is what makes this picture and landscape intriguing. What caused it to look this way?
» Read more

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Ispace signs deals with companies in India and Japan

The Japanese lunar lander startup Ispace today announced it has signed partnership deals with two different companies, OrbitAid in India and Toyota in Japan.

The startup OrbitAid is India’s first “on-orbit refueling company”. It will provide Ispace’s landers with standardized docking ports as well as refueling capabilities.

The two companies aim to demonstrate the critical capabilities required for mission extension in the cislunar environment, enabling long-duration lunar operations and paving the way for a sustainable lunar economy. The integration of OrbitAID’s SIDRP interface is expected to not only optimize refueling, recharging, and data transmission capabilities but also support ispace’s efforts to enhance the performance and reliability of its landers. By enabling lunar refueling, both companies plan to facilitate deep-space exploration beyond Earth’s orbit.

Toyota meanwhile will provide technical support to Ispace as it develops its own second generation lunar rover, dubbed Lunar Cruiser. Ispace is already prepping a smaller rover that will fly on its next lunar landing mission.

Ispace has been signing on a range of customers and commercial partners in recent months, even though its only two attempts to land on the Moon both failed just before touch down. It has contracts with NASA, ESA, and JAXA for future missions. These new deals appear designed to strengthen and extend its capabilities beyond simply landing on the Moon, but also to provide interplanetary spacecraft as well.

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Astrobotic’s Griffin lunar lander delayed again

Moon's south pole, with landers indicated

According to an update on the status of Astrobotic’s Griffin lunar lander posted on October 24, 2025, the company has now delayed the launch from the fall of 2025 to July 2026, apparently because the spacecraft is not yet assembled and its many components are still undergoing testing.

For example, none of Griffin’s four propellant tanks have yet been installed. Nor apparently has its core structure been fully integrated, with “tanks, ramps, attitude control thrusters, and solar panels” only now having completed “fit checks.”

The map to the right indicates the location where Griffin is supposed to land, about 100 miles from the Moon’s south pole. Nova-C, Intuitive Machines first attempt to soft land on the Moon, landed at the green dot, but failed when it fell over at landing. Intuitive Machines second lunar lander, Athena, also fell over when it landed in the same region that is now Griffin’s target landing zone.

Griffin has experienced repeated delays since the contract was issued to Astrobotic in 2020. The mission was originally supposed to launch in November 2023, carrying NASA’s Viper rover. In July 2022 however it was delayed one year to November 2024 because Astrobotic said it needed more time.

Sometime after the failure of Astrobotic’s first lunar lander, Peregrine, in January 2024, NASA once again delayed the Griffin mission, pushing it back another year to November 2025.

In July 2024 NASA canceled Viper, removing it as a payload from Griffin, because Viper was significantly overbudget and would not be ready for that fall 2025 launch. NASA however did not cancel Griffin. It appears however that Astrobotic wasn’t ready either for a launch in November, and thus this further delay.

Whether it will be ready by July remains unknown. Based on Astrobotic’s own update I have serious doubts. For a spacecraft that was supposed to originally launch in 2023, Griffin seems woefully unready now, two years past that date.

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Weird “What the heck?!” pedestal crater on Mars

A
Click for full image.

Cool image time! The picture to the right, cropped and reduced to post here, was taken on August 26, 2025 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). While the full image shows what the camera team labels as the “ridges” that cover this area, the most prominent feature in the whole landscape is this half-mile-wide pedestal crater, sitting about 50 to 100 feet above the surrounding terrain.

What makes this strange butte so weird is the plateau on top, criss-crossed with ridges and hollows in a manner that defies any obvious geological explanation.

Pedestal craters are not uncommon on Mars, and in fact a bunch of others are found throughout this region. The theory for their formation is that they formed when the surface here was much higher. The impact made the crater floor more dense and resistant to erosion, so as the surrounding terrain wore aware the crater ended up being a butte.

However, pedestal craters usually have relatively smooth tops, making this crater another example of a “What the heck?” image.
» Read more

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The second known asteroid discovered orbiting closer to the Sun than Venus

Using ground-based telescopes scanning the morning and evening sky, an astronomer has discovered only the second known asteroid circling the Sun within the orbit of Venus.

The manner of the discovery itself, by Scott Sheppard of the Carnegie Institution, also illustrated our modern world.

He first observed it using the Cerro Tololo Dark Energy Camera the night before leaving on a hiking trip. Because the object was moving fast, he knew it must be very close to the Sun, so he’d need to image it again and soon to confirm its orbit before it became lost in the Sun’s glare.

“I had to schedule new observations to re-observe the object while deep in the forest of Pennsylvania,” he says. “It is just amazing that even camp sites today have good Wi-Fi access — that allowed me to download the new second observations of this asteroid and determine its unique orbit that is interior to Venus.”

Astronomers have found so few asteroids close to the Sun because the Sun’s glare makes observations difficult. Some scientists like to speculate to the press that there could be a large unknown population, with some posing a threat to Earth. The computer predictions however say the population is small, because the push of the Sun’s light and radiation should easily shift their orbits outward or make them unstable.

The two asteroids so far found confirm these models in a counter-intuitive way. The new asteroid is estimated to be a little less than a half mile across, while the previously discovered asteroid is thought to have a diameter of more than a mile. Their larger size makes it harder for the Sun’s light and radiation to shift their orbit.

In other words, this inner population of asteroids is likely to be low in number, but made up of larger objects.

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A somewhat typical volcanic vent on Mars

Overview map

With today’s cool image we begin with the overview map to the right. The white dot marks the location, within the region on Mars dubbed the Tharsis Bulge, where four of its biggest volcanoes are located on a surface that has been pushed significantly above the red planet’s mean “sea level.”

The small rectangle in the inset shows the area covered by the cool image below. The focus is on a two-mile-long and half-mile-wide depression that sits on a relatively flat landscape of few craters.

If you look at the inset closely, you will notice this depression is surrounded by a dark borderline on all four sides, ranging in distance from three to thirteen miles. The grade to that borderline is downhill in all directions, with the drop ranging roughly from 800 to 1,000 feet.

So what are we looking at? » Read more

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Small fresh impact on Mars’ youngest major lava flow

Monitoring a fresh impact on Martian lava
Click for original image.

Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken on August 26, 2025 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).

The camera team labels this “Monitoring New Impact Site.” The fresh impact, indicated by the three dark patches just left and up from center, is actually not that fresh. It was first photographed by MRO on September 27, 2008. This newer picture is to see if anything significant had changed in the subsequent seventeen years.

In comparing the two pictures, the only change that is obvious is that the patches have faded and become less distinct. Nothing else appears different.

The surrounding terrain however is interesting in its own right. The landscape is remarkably flat, though it has that meandering ridge coming out from that lighter patch in the lower right. What are we looking at?
» Read more

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Meandering channel in Mars’ southern cratered highlands

Meandering channel on Mars
Click for original image.

Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken on August 30, 2025 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).

Dubbed a “channel” by the MRO science team, it shows us a meandering canyon with a floor that seems filled with corroded linear features seen frequently on Earth glaciers. Here, the linear ridges appear broken, in many places missing, and in other places so broken their linear nature disappears.

If this was on Earth and I was a global warming activitist, I would immediately claim that the glacier has been evaporating away due to a warming climate caused by SUVs and Republican intransigence. This however is on Mars, where there are no SUVs or Republicans. So what is going on?
» Read more

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If there is any microbiology on Mars, new research says it will be found in the red planet’s ample ice

The uncertainty of science: New research that attempted to simulate conditions in the ice on Mars has determined that ancient microbes are more likely survive there for very long periods, as much as fifty million years, rather than the red planet’s dry sediments.

The research team, led by corresponding author Alexander Pavlov, a space scientist at NASA Goddard — who completed a doctorate in geosciences at Penn State in 2001 — suspended and sealed E. coli bacteria in test tubes containing solutions of pure water ice. Other E. coli samples were mixed with water and ingredients found in Mars sediment, like silicate-based rocks and clay.

The researchers froze the samples and transferred them to a gamma radiation chamber at Penn State’s Radiation Science and Engineering Center, which was cooled to minus 60 degrees Fahrenheit, the temperature of icy regions on Mars. Then, the samples were blasted with radiation equivalent to 20 million years of cosmic ray exposure on Mars’ surface, vacuum sealed and transported back to NASA Goddard under cold conditions for amino acid analysis. Researchers modelled an additional 30 years of radiation for a total 50-million-year timespan.

In pure water ice, more than 10% of the amino acids — the molecular building blocks of proteins — from the E. coli sample survived the simulated 50-million-year time span, while the samples containing Mars-like sediment degraded 10 times faster and did not survive. A 2022 study by the same group of researchers at NASA found that amino acids preserved in a 10% water ice and 90% Martian soil mixture were destroyed more rapidly than samples containing only sediment.

In other words, if there was ever microbiology on Mars, it is very unlikely Perseverance or Curiosity will ever find any, roving as they are in the dry Martian tropics.

Though this work has many uncertainties, especially in its assumption that it successfully simulated a 50-million-year time span, the result is hardly an earth-shaking discovery. If anything, it confirms the obvious, which is why NASA’s ludicrous claim that Perseverance’s prime mission is to look for life has always been a lie. It is traveling in the wrong place, a fact that was self-evident from the start.

Whether any microbiology might exist in Mars’ ice however is unknown. The odds are very very low, but not zero. If it does, it is even less likely it is living, based on orbital data.

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Layers of Martian ash

Layering on Mars
Click for original image.

Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken on August 31, 2025 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).

The science team labels this as “layering”, which surely is an apt description. As the latitude is 9 degrees south, this location is within the dry tropics of Mars, where no near surface ice has yet been found. Thus, the terraced layers of this low 20-foot-high mesa are not indicative of the many glacial climate cycles found in the mid-latitudes.

Instead, we are looking at sedimentary layers of rock or dust, laid down over time and later exposed by erosion.

So what caused the layers? And what is causing them to be exposed, one by one? As always the overview map helps provide a possible explanation.
» Read more

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