Tag: exploration

Hubble eyes the Egg Nebula

10:48 am

Hubble eyes the Egg Nebula
Click for original image.

Cool image time! The picture to the right, reduced to post here, was taken by the Hubble Space Telescope as part of a study of “preplanetary nebula,” the initial stages of a planetary nebula that forms as some star types begin dying. From the caption:

Many preplanetary nebulae are relatively dim and hard to spot. They are made of layers of gas ejected by the star, but that star is not yet hot enough to ionise the gas and cause it to glow. The Egg Nebula is relatively unique, easily visible as a sparkling jewelled egg in space. Powerful beams of starlight blast out of the inner cloud, two a-side, giving a breathtaking illumination to this cosmic structure. Fast-moving outflows of hot molecular hydrogen also emerge from within the dust cloud, visible just at the base of the searchlight beams. These outflows glow with infrared light, which is shown in this image by orange highlights.

The central cloud of dust is surrounded by concentric rings, themselves made up from thin, faint arcs of gas. These were created by successive outbursts from the central star, which ejected a little more material from its outer surface every few hundred years. The beams of starlight are reflected by these layers of gas, creating an appearance like ripples on the surface of water. The way that gas molecules reflect and scatter light gives a bluish colour to the arcs. The reflected starlight reveals important details about the central star, which is impossible to view directly in its dusty shell.

Many planetary nebula get their spectacular shapes because they have a binary star system in their center, that act like the blades in a blender as they circle each other, mixing the materials the stars’ eject to form those shapes. Because of those surrounding shells, it is often impossible to determine with the nebula has a single central star, or a binary system.

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How Saturn’s moon Enceladus causes an aurora on Saturn

9:38 am

Enceladus orbiting Saturn
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Using data collected by the orbiter Cassini while it orbited Saturn more than a decade ago, scientists now think they have mapped out how the moon Enceladus interacts with Saturn’s magnetic field and helps create an aurora in Saturn’s polar regions.

You can read the paper here. The artist rendering to the right comes from the press release, and shows that interaction. From that release:

The study, published in the Journal of Geophysical Research: Space Physics, shows how wave structures, known as ‘Alfvén wings’, travel like vibrations on a string along magnetic field lines connecting Enceladus to Saturn’s pole. The initial ‘main’ Alfvén wing is reflected back-and-forth both by Saturn’s ionosphere and the plasma torus that encircles Enceladus’s orbit, resulting complex and structured system. By using a multi-instrumental approach, researchers were able to show that the influence of Enceladus extends over a record distance of over 504,000 km – more than 2,000 times the moon’s radius.

…As well as the large-scale structures, the team found evidence that turbulence teases out the waves into filaments within the main Alfvén wing. This fine-scale structure helps the waves bounce off Enceladus’s plasma torus and reach the high-latitudes in Saturn’s ionosphere where auroral features associated with the moon form.

The white haze below Enceladus in the graphic represents the material that comes out of the “tiger stripe” fractures near its south pole.

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A lava tube on Venus?

9:18 am

Theorized lava tube on Venus

The uncertainty of science: Scientists in Italy have reanalyzed the radar data of Venus by the Magellan orbiter from 1990 to 1992 and concluded that at least one open pit on the side of a shield volcano might be the entrance to a underground lava tube.

You can read their paper here [pdf]. The graphic above comes from figures 2 and 3 of their paper, with the radar image of the pit to the right, and the cartoon to the left their interpretation of that radar data. From the abstract:

Between 1990 and 1992, the Synthetic Aperture Radar (SAR) instrument on board the Magellan spacecraft mapped the Venusian surface. By leveraging a SAR imaging technique developed for detecting and characterizing accessible subsurface conduits in the proximity of skylights, we analysed
the Magellan radar images in locations where there is evidence of localized surface collapses. Our analyses reveal the existence of a large and open subsurface conduit in the Nyx Mons region. This feature is hypothesized to be a pyroduct, characterized by a diameter of about 1 km, a roof thickness of at least 150 m and an empty void height of no less than 375 m. The conduit extends in the subsurface for at least 300 meters from the skylight.

To strengthen their conclusions, which are based on a LOT of assumptions, the scientists also compared this radar data with radar data taken of similar-sized lava tube skylights on Earth.

Their conclusion is reasonable, as Venus is a planet of volcanoes, with more than a million detected in radar data. Lava tubes should exist. Nonetheless, their interpretation of the radar data is very uncertain, and must be viewed with a great deal of skepticism.

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India picks landing site for its Chandrayaan-4 lunar sample return mission

10:22 am

Landing sites at the Moon's South Pole

Scientists at India’s space agency ISRO have now picked [pdf] a preliminary landing site for its planned Chandrayaan-4 lunar sample return mission, scheduled to launch in 2028.

[Four] sites of Mons Mouton area was fully characterised with respect to terrain characteristics using high resolution OHRC multiview image datasets and it was found that 1km x 1km area around MM-4 (-84.289, 32.808) contains the less hazard percentage, mean slope of 5°, Mean height of 5334m and most number of hazard free grids of size 24m x 24m. Hence MM-4 can be considered for the potential site of Chandrayaan-4 mission.

The study area of all four sites is indicated on the map to the right by the red dot labeled “Chandrayaan-4”. This mountain, Mons Mouton, is essentially a flat plateau between the numerous craters in the south pole region (many with permanently shadowed craters). Intuitive Machines second lander, Athena, attempted a landing there last year, and tipped over, as did that company’s first lander, Odysseus, both indicated in green. Astrobotic’s Griffin lander (yellow) is targeting this mountain also, hopefully to launch later this year.

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One of Cassini’s first close-up images of Saturn’s rings

12:48 pm

The rings of Saturn
Click for original image.

Cool image time! My exploration of the Cassini image archive continues. The picture to the right, reduced and enhanced to post here, was taken on May 2, 2005 by Cassini soon after it moved into a close orbit of Saturn where it could get high resolution images of Saturn’s rings. This is one of the first.

This is also a raw image that has not been calibrated or validated, to use the science team’s terms. Thus, the white dots scattered across the image could be artifacts that need to be cleaned up, not examples of Saturn’s many moons.

Regardless, the image illustrates the incredible delicacy of these rings, despite the fact that they are gigantic, spanning almost 45,000 miles in width, with a thickness ranging from 30 to 1,000 feet. And yet, there are so many distinct rings they almost resemble an old-fashioned vinyl record.

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Pluto’s implausible atmosphere, as seen in 2015 by New Horizons

2:07 pm

Pluto's implausible atmosphere
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Cool image time! The picture to the right, cropped to post here, was taken on July 14, 2015 by the camera on the New Horizons probe as it flew past Pluto, the only time a human craft has gotten close to this distant planet. From the link:

These high phase angle images show many artifacts associated with scattered sunlight; the Sun was less then 15 degrees from the center of the LORRI frame for these observations. But the outline of Pluto and its hazy atmosphere are also visible.

To see the atmosphere the light from the planet itself has been blocked out.

What is implausible about Pluto’s atmosphere is the location of the planet, about 3.7 billion miles from the Sun, out in the nether reaches of the solar system. At that distance sunlight is very weak, and produces very little energy. And yet, there is enough energy here to produce an atmosphere of mostly nitrogen gas, with trace amounts of metane and carbon monoxide. Scientists think this atmosphere only exists when Pluto is closer to the Sun in its somewhat oblong orbit, and freezes out the rest of the time. As Pluto was just retreating in 2015 from that closest approach in the last two decades of the 20th century, New Horizons could detect its presence.

But then, we really can’t be sure if this atmosphere truly vanishes when the planet is farthest from the Sun, as we have only so far observed 96 years in Pluto’s 248-year orbit.

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Astronomers use SphereX infrared space telescope to study interstellar Comet 3I/Atlas

8:32 am

False color images of SphereX infrared data
False color images of SphereX infrared data.
Click for original.

Using NASA’s SphereX infrared space telescope, astronomers have now detected a range of new molecules in the coma surround interstellar Comet 3I/Atlas as that coma brightened and grew in December 2025 following the comet’s closest approach to the Sun in the fall.

You can read the research paper here. From the press release:

In a new research note, mission scientists describe the detection of organic molecules, such as methanol, cyanide, and methane. On Earth, organic molecules are the foundation for biological processes but can be created by non-biological processes as well. The researchers also note a dramatic increase in brightness two months after the icy body had passed its closest distance to the Sun, a phenomenon associated with comets as they vent water, carbon dioxide, and carbon monoxide into space.

In every way this interstellar object continues to behave like an ordinary comet, which is actually quite profound. It tells us the rest of the universe is not that different than our solar system.

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One of Saturn’s many weird moons

11:47 am

Saturn's moon Atlas
Click for original image.

Cool image time! The picture to the right, cropped and reduced to post here, was taken on April 13, 2017 by the orbiter Cassini as it began it last close loops around Saturn before diving into its atmosphere to burn up.

Those close loops allowed it to get good close-up images of a few of the tiny moons that orbit in or close to the gas giant’s rings. On the right is one of those pictures, of the moon Atlas, taken from a distance of about 10,000 miles.

The moon’s weird ravioli shape is thought to be caused by the accretion of dust and ice from the nearby rings along Atlas’s equator.

Scientists also found the moon surfaces to be highly porous, further confirming that they were formed in multiple stages as ring material settled onto denser cores that might be remnants of a larger object that broke apart. The porosity also helps explain their shape: Rather than being spherical, they are blobby and ravioli-like, with material stuck around their equators. “We found these moons are scooping up particles of ice and dust from the rings to form the little skirts around their equators,” Buratti said. “A denser body would be more ball-shaped because gravity would pull the material in.”

Atlas itself is about 25 miles wide and about 11.5 miles thick, at its thickest point. I suspect if you tried to walk on it you would sink into the accumulated dust and ice, as it is likely no more dense as newly fallen snow.

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Pluto and Charon come out of the dark

1:40 pm

Pluto and Charon come out of the dark
Click for original image.

Cool image time! I have decided to start delving into the archives of some of the older planetary missions, because there is value there that is often forgotten now years later, that should not be forgotten.

In looking through the archive of images from the main camera on New Horizons as it sped past Pluto in July 2015, I found the picture to the right, taken on July 10, 2015 when New Horizons was still about three million miles away.

This is the raw image from that camera, cropped, reduced, and sharpened to post here. It is also the first time in human history we had a sharp look at these two planets that sit at the outer fringes of the solar system. The science team that day released a version that they enhanced to bring out the details, which I immediately posted. They then noted the following:

A high-contrast array of bright and dark features covers Pluto’s surface, while on Charon, only a dark polar region interrupts a generally more uniform light gray terrain. The reddish materials that color Pluto are absent on Charon. Pluto has a significant atmosphere; Charon does not. On Pluto, exotic ices like frozen nitrogen, methane, and carbon monoxide have been found, while Charon’s surface is made of frozen water and ammonia compounds. The interior of Pluto is mostly rock, while Charon contains equal measures of rock and water ice. “These two objects have been together for billions of years, in the same orbit, but they are totally different,” said Principal Investigator Alan Stern of the Southwest Research Institute (SwRI), Boulder, Colorado.

This difference is quite clear in the raw image, with Charon markedly dimmer than Pluto even though they are getting the same amount of light from the Sun.

More than any other objects in the solar system, the double planet system of Pluto-Charon demonstrates how uniquely different every object in the solar system is from every other object. Even when formed together, as these two planets were, they formed in a manner that made them drastically different.

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A galaxy’s swirling dust lanes

12:07 pm

A galaxy with swirling dust lanes
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Cool image time! The picture to the right, cropped, reduced, and enhanced to post here, was taken by the Hubble Space Telescope as part of follow-up observations of a now faded supernovae that occurred there two years earlier.

This was on purpose: the aim of the observations was to witness the aftereffects of the supernova and examine its surroundings, which can only be done once the intense light of the explosion is gone.

The galaxy itself, NGC 7722, is 187 million light years away, and is unusual in itself.

A “lenticular”, meaning “lens-shaped”, galaxy is a type that sits in between the more familiar spiral galaxies and elliptical galaxies. It is also less common than these — partly because when a galaxy has an ambiguous appearance, it can be hard to determine if it is actually a spiral, actually an elliptical galaxy, or something in between. Many of the known lenticular galaxies sport features of both spiral and elliptical galaxies. In this case, NGC 7722 lacks the defined arms of a spiral galaxy, while it has an extended, glowing halo and a bright bulge in the center similar to an elliptical galaxy. Unlike elliptical galaxies, it has a visible disc — concentric rings swirl around its bright nucleus. Its most prominent feature, however, is undoubtedly the long lanes of dark red dust coiling around the outer disc and halo.

The streak in the lower left is a very distant background galaxy, seen on edge.

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Comet K1/Atlas has broken apart, not interstellar Comet 3I/Atlas

10:37 am

the end of Comet K1/Atlas

CORRECTION: The image to the right is not that of interstellar Comet 3I/Atlas, as I reported earlier today. I misread the Gemini Telescope release. This is comet K1/Atlas, another comet from our own solar system that made its close approach to the Sun in October, when it broke up.

The the latest image from the Gemini North Telescope in Hawaii shows at least four sections slowly drifting apart.

The picture to the right, cropped to post here, was taken on December 6, 2025. Gemini’s previous image, taken in November 11th, shows about the same number of objects, but clustered much more closely together.

It appears that as the comet made its closest approach, the stress was too great. This is not surprising, as it happens to many comets that get too close to the Sun.

Sorry for the error and hat tip to reader Tom Laskowski for letting me know. I need to look at the names of comets named after the ATLAS telescope, as they are very similar and most are NOT interstellar comet 3I/Atlas.

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Pluto’s mountains of ice surrounded by a sea of frozen nitrogen

2:18 pm

Ice mountains floating in nitrogen sea on Pluto
Click for original image.

Cool image time! Though we only have a limited archive of high resolution pictures of Pluto that were taken when New Horizons did its close fly-by of the planet in July 2015, it is worthwhile sometimes to take a second look at some of those images. The picture to the right, cropped and annotated to post here, was taken during that July 14, 2015 fly-by, and shows a mountainous region dubbed Al-Idrisi Montes on the shore of a white frozen ocean. The red dotted line indicates a large trench that separates the Al-Idrisi mountains from the mountainous region to the west.

Sounds similar to an arctic shoreline here on Earth, doesn’t it? Not in the least. Those mountains, ranging from 600 to 9,000 feet high, are made of frozen ice, which on Pluto are as hard as granite due to the endless cold. And the white frozen ocean is frozen nitrogen, broken into polygon shaped blocks. Even stranger: those ice mountains might even be floating in that nitrogen sea! A paper from 2019 [pdf] looked at the New Horizons data and concluded as follows:

Evidence suggests that the Al-Idrisi mountains may have been uplifted by the formation of
the western trench feature. Solid state convection appears to be our best supposition as to how the Al-Idrisi Montes reached their heights.

In other words, as that large trench/depression formed, convection (the bubbles you see when you simmer tomato sauce) pushed these mountains of ice upward to float above the “sea level” of that nitrogen sea.

At least, that’s one hypothesis. The scientists who wrote this paper admit their “our hypothesis still remains in need of study and this trench-mountain system warrants serious further research.” In other words, we simply don’t know enough to have a definitive understanding of the geology of this extremely alien planet.

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Saturn’s rings with two of its moons perfectly aligned

2:30 pm

Two of Saturn's moons above its rings
Click for original image.

Cool image time! Rather than posting another Mars orbital image, I decided today to delve into the archive of pictures taken by the Cassini orbiter during the thirteen years it circled Saturn, from 2004 until 2017. The picture to the right, cropped to post here, was released on December 14, 2015, and is just one example of the many breath-taking photographs that the Cassini science team took during that mission. From the caption:

Like a cosmic bull’s-eye, Enceladus and Tethys line up almost perfectly for Cassini’s cameras. Since the two moons are not only aligned, but also at relatively similar distances from Cassini, the apparent sizes in this image are a good approximation of the relative sizes of Enceladus (313 miles across) and Tethys (660 miles across).

This view looks toward the un-illuminated side of the rings from 0.34 degrees below the ring plane. The image was taken in red light with the Cassini spacecraft narrow-angle camera on Sept. 24, 2015.

The image was obtained at a distance of approximately 1.3 million miles from Enceladus. Image scale on Enceladus is 7 miles per pixel. Tethys was at a distance of 1.6 million miles with a pixel scale of 10 miles per pixel.

Enceladus is in the foreground, and is the planet that has what scientists have labeled tiger stripe fractures that vent water and other material, including carbon molecules.

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Astronomers discover a “surprisingly mature” cluster of galaxies in early universe

11:18 am

Proto galaxy cluster
Click for original image.

The uncertainty of science strikes again! Astronomers using both the Webb Space Telescope and the Chandra X-ray Observatory now think they have discovered a just-forming protocluster of galaxies only one billion years after the Big Bang, when such galaxy clusters should not yet exist.

You can read their paper here [pdf]. The image to the right, cropped and reduced to post here, shows the Webb infrared data as the background of stars and galaxies, with the galaxies thought to be part of this protocluster circled. The blue cloud is Chandra’s X-ray data. From the press release:

The Chandra and Webb data reveal that JADES-ID1 contains the two properties that confirm the presence of a protocluster: a large number of galaxies held together by gravity (Webb sees at least 66 potential members) that are also sitting in a huge cloud of hot gas (detected by Chandra). As a galaxy cluster forms, gas falls inward and is heated by shock waves, reaching temperatures of millions of degrees and glowing in X-rays.

What makes JADES-ID1 exceptional is the remarkably early time when it appears in cosmic history. Most models of the universe predict that there likely would not be enough time and a large enough density of galaxies for a protocluster of this size to form only a billion years after the big bang. The previous record holder for a protocluster with X-ray emission is seen much later, about three billion years after the big bang.

It increasingly appears that there are aspects of the universe we simply do not yet understand, which in turn make our theories of its birth and formation either incomplete or invalid. Those theories might be right in principle, but the data suggests they are wrong in detail.

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Webb finds another unexpected galaxy in the very early universe

9:25 am

Unexpected galaxy
Click for original image.

The uncertainty of science: Using the Webb Space Telescope, astronomers have discovered another galaxy in the very early universe that appears too bright and developed for it to even exist so soon after the Big Bang.

MoM-z14 is one of a growing group of surprisingly bright galaxies in the early universe – 100 times more than theoretical studies predicted before the launch of Webb, according to the research team. “There is a growing chasm between theory and observation related to the early universe, which presents compelling questions to be explored going forward,” said Jacob Shen, a postdoctoral researcher at MIT and a member of the research team.

…With galaxy MoM-z14 existing only 280 million years after the big bang, there was not enough time for generations of stars to produce such high amounts of nitrogen in the way that astronomers would expect. One theory the researchers note is that the dense environment of the early universe resulted in supermassive stars capable of producing more nitrogen than any stars observed in the local universe.

All theories about the Big Bang and the early universe did not predict the existence of this galaxy, or a bunch of others that Webb has now detected.

The false color infrared Webb image is to the right, cropped and reduced to post here. The full image covered a much larger area, so this tiny galaxy was not easy to find. Scientists identified it by the very high red shift of its light, due to the expansion of the universe and it being so far away. That expansion away from us causes the wavelengths of its light to stretch into the infrared so that only Webb can see it.

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Scientists produce new estimate of the thickness of Europa’s icy crust

5:23 pm

Europa in true color
Europa in true color, taken by Juno during that
September 2022 fly-by. Click for full image.

Using data produced by Juno during a 2022 close-fly of Jupiter’s moon Europa, scientists have made a new estimate of the thickness of Europa’s icy crust, approximately 18 miles thick with a 6-mile margin of error.

In other words, their estimate could be as small as 12 miles thick, or as large as 24 miles thick.

You can read their paper here. From their abstract:

For the idealized case of pure water ice, the data are consistent with the existence of a thermally conductive ice shell with a thickness of 29 ± 10 km [18 ± 6 miles] and with the presence of cracks, pores or other scatterers extending to depths of hundreds of metres below the surface with a characteristic size smaller than a few centimetres in radius. An ice-shell salinity of 15 mg kg−1, as indicated by models based on terrestrial marine ice, would reduce our estimate of the thickness of the ice shell by about 5 km, substantially less than our 10 km uncertainty. The low volume fraction, small size and shallow depth of the scatterers indicate that the fracture interfaces observed at Europa’s surface are alone unlikely to be capable of carrying nutrients between the surface and the ocean. [emphasi mine]

The highlighted sentence is the important one. If this new estimate is right, than the unidentified reddish material that appears to leak out of the long ridgelike cracks on Europa’s surface, clearly visible in the picture to the right, are not coming from any underground ocean. The distances are too large.

Other estimates have suggested that ice crust could be as thin as 2 miles, but like this research the uncertainties are very large.

Meanwhile, the Juno mission is still alive, though essentially winding down operations. The mission was expected to officially end at the end of September 2025, when its budget ran out, but the just passed budget included enough money to keep it going, albeit at a relatively low level. According to the orbiter’s webpage, it will continue to orbit Jupiter, its orbit degrading naturally until it falls into Jupiter to burn up. As it does so data will continue to be collected, though at a much lower rate.

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Windswept Martian volcanic ash?

2:35 pm

Volcanic ash on Mars?
Click for original image.

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

The science team labels this simply as “Features,” the vagueness of which I can understand after digging in to get a better idea of the location and geography.

The location, as shown by the white dot on the overview map below, is inside the Medusa Fossae Formation, the largest volcanic ash field on Mars that is thought to be the source of much of the red planet’s dust. That ash field is large and very deep, and was put down more than a billion years ago when the giant volcanoes of Mars were active and erupting. Thus it is well layered, and many images of that ash field show that layering exposed by the eons of Martian wind scouring its surface.

In this case, that scouring appears to have produced this feathery surface, though the origin of those ridges might have instead come from volcanic flows that are now hardened. Or we could be looking at ancient channels produced by ice or water, though that would have to have been a very long time ago, as this image is located in the Martian dry tropics, where no near surface ice presently exists.
» Read more

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Astronomers use AI to discover hundreds of weird galaxies in Hubble archive

10:23 am

Weird galaxies in the Hubble archive, found with AI
Click for original image.

In what is a perfect example of the proper use of artificial computer intelligence (AI), astronomers have now used this programming to analyze almost 100 million images taken by the Hubble Space Telescope over the decades to find any galaxies hidden there that have “anomalies” or unusual shapes.

The team analyzed nearly 100 million image cutouts from the Hubble Legacy Archive, each measuring just a few dozen pixels (7 to 8 arcseconds) on a side. They identified more than 1,300 objects with an odd appearance in just two and a half days — more than 800 of which had never been documented in scientific literature.

The six galaxies to the right are just a small sample. All six were previously unidentified, and include “three lenses with arcs distorted by gravity, one galactic merger, one ring galaxy, and one galaxy that defied classification” (the galaxy at the top left). From the European Space Agency’s (ESA) press release:

The strange, bi-polar galaxy seen here is certainly anomalous, with its compact, swirling core and two open lobes at the sides. Exactly what kind of galaxy it is is unclear, and it was not previously known to astronomers.

As noted in the first link, the volume of data that astronomers are now collecting from ground-based and orbiting telescopes — many of which are survey telescopes that photograph the entire sky repeatedly — has actually become a problem. They have great data, but don’t have the time or human resources to study it sufficiently. Even employing large numbers of ordinary citizens, working at home with their own computers, can’t get the job done.

This is the kind of grunt work that AI is ideally made for. It can quickly review the data and identify objects that don’t fit normal expectations. Humans then can do the real work, finding the most interesting of these strange objects, such as the top left galaxy, and devote human creativity to studying it.

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New gullies on Mars?

12:08 pm

Fresh gullies on Mars?
Click for original image.

Cool image time! The picture to the right, cropped and reduced to post here, was taken on November 6, 2025 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).

The science team labels this image “Fresh-Looking Gullies.” It was clearly taken to study the gullies flowing down the north interior crater wall of this 4.4 mile-wide unnamed crater, about 1,500 feet deep.

What causes these gullies remains an open question. They are found in many places in the Martian mid-latitudes. When first discovered scientists thought they might be related to the sublimation of underground ice. More recent research suggests they are formed by the seasonal dry ice frost cycle that in the high latitudes has carbon dioxide condense to fall as snow in autumn and then sublimate away in the spring.
» Read more

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Computer simulations suggest Jupiter and Saturn have fundamentally different interiors

9:57 am

The different polar vortexes of Jupiter and Saturn

The uncertainty of science: In attempting to explain why the polar vortexes of Jupiter and Saturn are so different, scientists running large computer simulations have found that the difference could be because Jupiter’s interior is “softer” than Saturn’s.

The two images to the right illustrate the different polar vortexes of both planets. Jupiter’s (top) is made up of multiple chaotic small storms that form a hexagon-like ring around the pole. Saturn’s (bottom) is a single very coherent hexagon-shaped storm.

Over multiple different simulations, they observed that some scenarios evolved to form a single large polar vortex, like Saturn, whereas others formed multiple smaller vortices, like Jupiter. After analyzing the combinations of parameters and variables in each scenario and how they related to the final outcome, they landed on a single mechanism to explain whether a single or multiple vortices evolve: As random fluid motions start to coalesce into individual vortices, the size to which a vortex can grow is limited by how soft the bottom of the vortex is. The softer, or lighter the gas is that is rotating at the bottom of a vortex, the smaller the vortex is in the end, allowing for multiple smaller-scale vortices to coexist at a planet’s pole, similar to those on Jupiter.

Conversely, the harder or denser a vortex bottom is, the larger the system can grow, to a size where eventually it can follow the planet’s curvature as a single, planetary-scale vortex, like the one on Saturn.

If this mechanism is indeed what is at play on both gas giants, it would suggest that Jupiter could be made of softer, lighter material, while Saturn may harbor heavier stuff in its interior.

This conclusion however runs completely counter to what we should expect. Jupiter has a much great mass, and one would assume from this that its interior would therefore be denser and thus harder.

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A 10-mile-long avalanche on Mars

11:32 am

Overview map

A ten mile long avalanche on Mars
Click for original image.

Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken on November 8, 2025 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows only three miles of a ten-mile-long avalanche inside the solar system’s largest canyon, Valles Marineris.

The white dot on the overview map above marks the location. In the inset the white rectangle indicates the area covered by the picture to the right. I have indicated the avalanche’s full extent beyond this.

Overall, the landslide fell about one mile along those ten miles. That there are about a dozen small craters on top of the slide tells us this happened quite a long time ago.

As always, the scale of Valles Marineris boggles the mind. Though this avalanche fell about 5,000 feet (the same depth of the south rim of the Grand Canyon), that drop only covered one fifth of Valles Marineris’s depth. At this point, from the rim to the floor the elevation difference is about 23,000 feet, which would place the rim among the 100 highest mountains on Earth. And of course, this is only one small spot in this gigantic canyon that runs 2,500 miles east-to-west, with its depth about the same that entire length.

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Martian glacier flowing past small peak

12:32 pm

Overview map

Martian glacier flowing past small peak
Click for original image.

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

As is proper, the science team labels this vaguely as a “flow obstacle in lobate debris apron.” The obstacle is that small peak. The lobate debris apron is the material flowing past, resembling in almost all details what a glacier looks like on Earth. The scientists use vague terms because they don’t want to trap themselves into a conclusion before it is confirmed.

Nonetheless, based on all the data MRO and other Mars orbiters have been gathering for the past decade, we are almost certainly looking at near-surface ice flowing downhill and past that peak.

The white dot in the overview map above marks the location, on the western end of the 2,000-mile-long mid-latitude strip I label “glacier country,” because practically every image from this region shows features such as this.

The arrow in the inset shows the direction of the downhill grade, dropping from 2,000 to 3,000 feet from the surrounding plateau. The peak itself rises about 130 feet above the flow on the uphill side, but 650 feet above on the downhill side. Apparently the flow piled up somewhat as it hit the peak.

That flow however is likely inactive at this time. Though the researchers have repeatedly monitored the many glacial flows they have found on Mars in the decade since MRO arrived in Mars orbit, so far I have heard of no example showing any movement. And that covers about five Martian years.

These images do prove one thing: Mars is not dry. It has plenty of water near the surface, though locked in ice.

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Exposed weirdness on floor of Martian crater

12:18 pm

Crazy shapes on floor of Martian crater
Click for original image.

Cool image time! The picture to the right, rotated, cropped, reduced, and sharpened to post here, was taken on November 27, 2025 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).

The science team labels this “exposed crater floor materials”. While properly vague, that hardly suffices. This image could easily fall into my “What the heck?!” category of Martian geology that is difficult to understand, no less explain.

The color strip suggests that dust dominates near the top and bottom, though dust is also present in the middle. The patches with the bluish tint in the middle suggests these lighter swirls and patches are bedrock.

Of course, none of that explains the weird shapes of these patches, nor why they exist at all.

Before delving into those weird shapes, we must note the two vertical black strips to the right of the color strip, indicating a gap in data. Such gaps have been appearing more frequently of late, suggesting MRO’s age, almost a decade in orbit around Mars, is beginning to show itself. A failure in 2023 in one filter band of the high resolution camera already leaves blank the color swath in black and white images. These new blank strips indicate further issues, warning us that we must be prepared for the loss of this camera and orbiter in the somewhat near future.
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No alien civilizations? After analyzing two decades of data SETI@Home produces 100 signals “worth a second look”

9:08 am

For more than two decades, from 1999 to 2020, the Search for Extraterrestrial Intelligence (SETI) project asked millions of people worldwide to loan it the use of their computers so the project to could analyze twelve billion signal detections that were of interest.

After 10 years of work, the SETI@home team has now finished analyzing those detections, winnowing them down to about a million “candidate” signals and then to 100 that are worth a second look. They have been pointing China’s Five-hundred-meter Aperture Spherical Telescope, a radio telescope referred to as FAST, at these targets since July, hoping to see the signals again.

Though the FAST data are not yet analyzed, [computer scientist and project co-founder David Anderson] admits he doesn’t expect to find a signal from ET.

At the link the SETI team outlined the many reasons, all quite reasonable, for the failure to detect any obvious signals from alien civilizations. The universe is vast, they only looked at a very tiny slice, the variations of signals are many, and the amount of data was still so gigantic analyzing it was endlessly time-consuming. Moreover, they might have been looking at the wrong wavelengths, and there is even the possibility that advanced civilizations simply don’t broadcast at any wavelengths.

Nonetheless, the project was not a failure. It showed it was possible to use a lot of home computers to create the equivalent of a super-computer. The technology and volunteer system it developed has since been used by other scientists on projects like looking for clouds on Mars and studying galaxy types.

The big question remains unanswered however. Considering the numbers of stars in the galaxy, and the recent data that shows most have planets, it seems strange that there have been so few candidate detections, and even these are questionable. Could it actually be the case that we are the first sentient intelligence species in the Milky Way?

There always has to be a first. That humanity might be that first is a mind-blowing thought.

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SpaceX launches NASA’s Pandora exoplanet space telescope

9:32 am

SpaceX today successfully launched a new NASA space telescope, Pandora, its Falcon 9 rocket lifting off from Vandenberg in California.

Pandora is a smallsat focused on studying 20 stars known to have transiting exoplanets. It will look at each repeatedly to draw as much information about the star and the exoplanet as possible. Also deployed were two other NASA smaller astronomy cubesats.

The Falcon 9 first stage completed its 5th flight, landing back at Vandenberg. The two fairing halves completed their first and seventh flights respectively.

At this moment, SpaceX is the only entity to have launched in 2026. This was its fourth launch.

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The first preliminary research into landing a Mars helicopter in the Starship landing zone

12:58 pm

Map of rotorcraft images in Starship landing zone

In early November 2025 I posted a cool image from Mars Reconnaissance Orbiter (MRO) that had the very provocative label “Characterize Possible Rotorcraft Landing Site”. While this was not the first such image taken by scientists using MRO to scout out potential landing zones for future Mars helicopter missions (see here and here), this particular image was one of several taken recently that were all within the candidate landing zone for SpaceX’s Starship spacecraft, focused specifically on the low Erebus mountain chain that sits within this part of Mars’ northern lowland plains.

In the January image download from MRO, I found another such image, taken on December 1, 2025. The map to the right shows that Starship candidate landing zone, with all the images taken for SpaceX indicated. The inset adds all the recent images taken for this “possible rotorcraft” mission, including the December image and the previous four (here, here, here, and here), with orange representing images already obtained and yellow those requested but pending.

I decided I needed to find out more, and tracked down the scientist who had requested the images, Eldar Dobrea of the Planetary Science Institute in Arizona. In response to my email, he explained:
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Icy Mars

2:26 pm

Overview map

Icy Mars

Today’s cool image once again illustrates the fact that most of Mars Mars is not a dry desert like the Sahara, as most news sources and the general public still believes, but a cold icy place similar to Antarctica, with plenty of near surface ice covering almost the whole planet, except for the dry equatorial regions (the one region we have sent almost all our landers and rovers).

The picture to the right, rotated, cropped, reduced, and sharpened to post here, was taken on November 26, 2025 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows one small section of the floor of an unnamed very old and eroded 82-mile-wide crater located in the northern mid-latitudes of Mars.

That location is indicated by the white dot on the overview map above. This part of the mid-latitudes is a region I dub “glacier country”, a 2,000-mile long strip where practically every image taken there shows very obvious glacial features.

Today’s image is no different. The 2-mile-wide crater in the upper left appears blobby, as if the impact had landed in mud. Its interior is filled with what the scientists believe is glacial debris. The surrounding landscape has a similar appearance, as if the ground was slushy and easily misshapen by seasonal temperature changes. To the southwest of the crater, within what appears to be a surrounding splash apron, there appears to be an eroded drainage channel, likely created by the flow of glacial ice downward.

So, when you read articles telling you Mars is dry and scientists are still hunting for water there, know that whomever wrote that article had no idea what he or she were talking about. The scientists studying Mars know that Mars has lots of water. Except for the tropics below 30 degrees latitude, there is near surface ice everywhere. Their questions revolve instead on figuring out how deep and extensive it is, and how it has shaped Mars’ overall geology.

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Second Escapade Mars orbiter completes a delayed engine burn

10:03 am

Engineers have now successfully placed both Escapade Mars orbiters in their parking orbit, the second orbiter completed the required engine burn after it was delayed due to unexpected telemetry during an earlier mid-course correction burn.

That unexpected telemetry suggested the engine was firing at a lower thrust than expected. Today’s update did not provide any additional information as to how the thrust issue had been solved or overcome. All it said was that both spacecraft will fire their engines in November 2026 as planned to head to Mars.

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Rubin Observatory’s first observations detects more than 2,000 asteroids

11:04 am

The first look patch, in which 2,103 asteroids were detected
The first look patch, in which 2,103 asteroids
were detected. Figure 1 of the paper.

Scientists have now published the first results from the Rubin Observatory in Chile during its on-going commissioning phase, during which they detected more than 2,000 asteroids in just one patch in the sky, most of which had been unknown previously and many rotating at record-breaking speeds.

You can read the paper here [pdf]. From the press release:

The study presents 76 asteroids with reliable rotation periods. This includes 16 super-fast rotators with rotation periods between roughly 13 minutes and 2.2 hours, and three ultra-fast rotators that complete a full spin in less than five minutes.

All 19 newly identified fast-rotators are longer than the length of an American football field (100 yards or about 90 meters). The fastest-spinning main-belt asteroid identified, named 2025 MN45, is 710 meters (0.4 miles) in diameter and it completes a full rotation every 1.88 minutes. This combination makes it the fastest-spinning asteroid with a diameter over 500 meters that astronomers have found.

All but one of these fast-rotators are in the main asteroid belt, with the exception a near-Earth asteroid.

This work essentially completes Rubin’s commissioning. It will begin full observations in 2026. From the paper:

Toward the start of 2026, the observatory will begin conducting the Legacy Survey of Space and Time (LSST), a decade-long campaign to repeatedly image the southern sky in multiple bands. The main LSST survey will use six filters spanning near-ultraviolet to near-infrared wavelengths, revisiting the same pointing twice each night, returning to take additional pairs every few nights. … The cadence is designed to result in a dataset capable of answering numerous and varied science cases, from understanding the nature of dark energy to discovering and characterizing millions of asteroids, comets, interstellar objects, and transneptunian objects (TNOs) in the solar system.

In building Rubin the astronomers have always thought their biggest problem was archiving and accessing this large dataset, and much work was spent developing a usable and accessible archive system. Even so, it will take thousands of scientists many decades to mine the discoveries that will be hidden there.

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Study: If Europa has an underground ocean, it is lifeless and dormant

9:43 am

Scientists analyzing the conditions that are believed to exist in Europa’s theorized underground ocean have concluded there is little geological activity within that ocean, reducing significantly the chances there is life there.

A new study led by Paul Byrne, an associate professor of earth, environmental and planetary sciences, at Washington University in St. Louis, throws cold water on the idea that Europa could support life at the seafloor. Using calculations that consider the moon’s size, the makeup of its rocky core and the gravitational forces from Jupiter, Byrne and a team of scientists conclude that Europa likely lacks the tectonic motion, warm hydrothermal vents or any other sort of underwater geologic activity that would presumably be a prerequisite for life.

“If we could explore that ocean with a remote-control submarine, we predict we wouldn’t see any new fractures, active volcanoes or plumes of hot water on the seafloor,” Byrne said. “Geologically, there’s not a lot happening down there. Everything would be quiet.” And on an icy world like Europa, a quiet seafloor might well mean a lifeless ocean, he added.

You can read the paper here [pdf]. It admits in its conclusion that these results have a lot of uncertainty, and the Europa Clipper mission, set to arrive in orbit around Jupiter in 2031, will reduce that uncertainty but not eliminate it, adding that “Ultimately, however, the true test of our results here will require directly accessing the ocean and, perhaps one day, the ocean floor itself.”

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