Tag: science

Galaxies without end

8:55 am

Galaxies without end
Click for original.

Cool image time! The picture to the right, reduced and enhanced to post here, was taken by the Hubble Space Telescope as part of a monitoring program studying the two supernovae that have occurred in this galaxy previously.

Hubble has turned its attention toward NGC 1309 several times; previous Hubble images of this galaxy were released in 2006 and 2014. Much of NGC 1309’s scientific interest derives from two supernovae, SN 2002fk in 2002 and SN 2012Z in 2012. SN 2002fk was a perfect example of a Type Ia supernova, which happens when the core of a dead star (a white dwarf) explodes.

SN 2012Z, on the other hand, was a bit of a renegade. It was classified as a Type Iax supernova: while its spectrum resembled that of a Type Ia supernova, the explosion wasn’t as bright as expected. Hubble observations showed that in this case, the supernova did not destroy the white dwarf completely, leaving behind a ‘zombie star’ that shone even brighter than it did before the explosion. Hubble observations of NGC 1309 taken across several years also made this the first time the white dwarf progenitor of a supernova has been identified in images taken before the explosion.

The image however carries a far more philosophic component. Except for the star near the top (identified by the four diffraction spikes), every single dot and smudge you see in this picture is a galaxy. NGC 1309 is about 100 million light years away, but behind it along its line of sight and at much greater distances are innumerable other galaxies, so many it is impossible to count them. And each is roughly comparable in size to our own Milky Way galaxy, containing billions of stars.

The scale of the universe is simply impossible to grasp, no matter how hard we might try.

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One of NASA’s two Tracers satellites just launched has an issue

10:17 am

During the commissioning phase shortly after their launch earlier this week, one of NASA’s two Tracers satellites designed to study the solar wind and its interaction with the Earth’s magnetic field has had an as yet unnamed issue.

During the commissioning process, the team made routine adjustments to the power subsystem on both vehicles. While the adjustments achieved the desired results on one satellite, the other satellite requires further investigation by the team. Commissioning operations are temporarily paused while the team analyzes the situation and determines the appropriate response.

Though the press release provides no other information, it appears the satellite is having a problem producing the power expected.

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Mars and its two moons seen in the infrared by Europa Clipper

10:37 am

Mars and its two moons
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Cool image time! The infrared image to the right, cropped, reduced, and enhanced to post here, was taken by Europa Clipper on February 28, 2025 just before it flew past Mars on its way to Jupiter.

Deimos is in the upper left corner, while Phobos is close to Mars.

When the image was taken by the mission’s Europa Thermal Emission Imaging System (E-THEMIS), the spacecraft was about 560,000 miles (900,000 kilometers) from the Red Planet. The image is composed of 200 individual frames, part of a continuous scan of 1,100 frames taken roughly a second apart over a period of 20 minutes. Scientists are using the tiny, point-like images of the moons to check the camera’s focus.

As this is an infrared image (measuring heat), it shows Mars’ northern polar cap as the dark oval at the top of the planet. The bright (and thus warmer) oval to the lower left is the shield volcano Elysium Mons.

This data suggests Europa Clipper’s thermal instrument is working as intended, which is essential for observing the ice content (if any) on Europa once it enters Jupiter orbit in 2030.

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The journal Science retracts 15-year-old paper that proposed arsenic as basic element of life

10:15 am

The death of science: Though numerous later research had rejected the conclusions of a 2010 research paper that had suggested a bacteria found at Mono Lake in Californa was using arsenic instead of phosphorus in its DNA, the journal Science that published that paper has now retracted it.

In a blog post accompanying this week’s retraction notice, Science’s current Editor-in-Chief Holden Thorp and Valda Vinson, executive editor of the Science family of journals, emphasize there is no suggestion of foul play in the GFAJ-1 paper. Instead, pointing to subsequent commentary and research that suggest some of the paper’s findings stem from contamination, not arsenic use by bacteria, they write: “Science believes that the key conclusion of the paper is based on flawed data.”

Speaking with Science’s News team, which operates independently from its research arm, study co-author and Arizona State University geochemist Ariel Anbar says the team disputes that assessment and has already addressed the referenced criticisms. “We stand by the data,” he adds.

Anbar added this in this report at Nature:

By contrast, one of the paper’s authors, Ariel Anbar, a geochemist at Arizona State University in Tempe, says that there are no mistakes in the paper’s data. He says that the data could be interpreted in a number of ways, but “you don’t retract because of a dispute about data interpretation”. If that’s the standard you were to apply, he says, “you’d have to retract half the literature”.

This action underlines the decline in open-mindedness in the academic field. It did not suffice to simply demonstrate in later papers that the paper’s conclusions were questionable. It was necessary to cancel it entirely, to airbrush it from history.

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The glaciers on Mars are almost pure ice with only a thin cover of dust and debris

9:55 am

A map of glaciers on Mars
A map of glaciers on Mars.

According to new research, scientists now think that the glaciers on Mars are almost pure ice, protected from sublimation by a thin cover of dust and debris.

Work over the last 20 years has demonstrated that at least some of these glaciers are mostly pure ice with only a thin cover of rock and dust, but according to a new paper published in Icarus, glaciers all over the planet actually contain more than 80% water ice, a significant finding. Ultimately, this means that Mars’s glacial ice deposits are nearly pure across the globe, providing a clearer understanding of Mars’ climate history and a possible resource for future utilization.

The researchers analyzed mid-latitude glaciers at five different locations in both the north and south hemispheres, and found that at every location the data suggested almost pure ice.

The map to the right, from earlier research, shows the prevalence of near-surface ice once you get above 30 degrees latitude. From the poles to the mid-latitudes it appears there is an ice sheet or “ice table” just below the surface. In the mid-latitudes glaciers dominate, as this appears to be the region where that ice is beginning to dissipate. In the equatorial regions little or no near-surface ice has been detected, though there has been some evidence in some places of ice at deeper depths.

This data once again demonstrates that Mars is not a desert like the Sahara, as we once believed. Instead, it more resembles Antarctica, where there is ice everywhere that simply needs to be processed for use.

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Study identifies range of interference produced by Starlink satellites

8:58 am

In analyzing about 76 million radio images produced by the new Square Kilometer Array (SKA) in Australia scientists have found within them signals produced by SpaceX’s Starlink satellites.

PhD candidate and study lead Dylan Grigg said the team detected more than 112,000 radio emissions from 1806 Starlink satellites, making it the most comprehensive catalogue of satellite radio emissions at low frequencies to date. “Starlink is the most immediate and frequent source of potential interference for radio astronomy: it launched 477 satellites during this study’s four-month data collection period alone,” Mr Grigg said. “In some datasets, we found up to 30 per cent of our images showed interference from a Starlink satellite.”

Mr Grigg said the issue wasn’t just the number of satellites, but the strength of the signals and the frequencies they were visible at. “Some satellites were detected emitting in bands where no signals are supposed to be present at all, such as the 703 satellites we identified at 150.8 MHz, which is meant to be protected for radio astronomy,” Mr Grigg said. “Because they may come from components like onboard electronics and they’re not part of an intentional signal, astronomers can’t easily predict them or filter them out.”

The researchers were careful to note that SpaceX has been following all international regulations, and that these signals are not a violation of any law or regulation. Further, they emphasized that “Discussions we have had with SpaceX on the topic have been constructive.”

Because many other such constellations are now being launched — with several from China that normally does not negotiate these issues like SpaceX — the scientists want new international regulations imposed to protect their work.

More and more it seems astronomers should simply move their operations into space or the Moon, where such issues will not exist. Getting above the atmosphere and away from our modern technological society provides so many benefits for research the move should be a no-brainer. That it is now also much cheaper to do it (thanks to SpaceX) makes the move even more practical.

For some reason however the idea seems too difficult for many astronomers to fathom.

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Curiosity amid the boxwork

12:13 pm

Curiosity amid the boxwork, looking uphill
Click for original image.

Overview map
Click for interactive map.

Cool image time! The panorama above, cropped to post here, was taken on July 20, 2025 by the left navigation camera on the Mars rover Curiosity. It looks uphill to the south into the canyon that Curiosity will eventually travel, with the white chaotic upper flanks of Mount Sharp on the horizon. The mountain’s peak itself is out of view, about 25 miles away.

The overview map to the right provides the context. The blue dot marks Curiosity’s present position, on the northern edge of the large patch of very distinct boxwork ridges visible from orbit. You can see these ridges in the foreground of the panorama above.

The yellow lines indicate the approximate area covered by the panorama. The red dotted line roughly indicates the rover’s future travels. At the moment, however, it is going nowhere, as the science team is focused on studying these boxwork ridges in the hope they can determine their origin. Such features are usually associated with cracking later filled with lava, with the polygon-shaped cracking usually associated with a formerly wet environment drying.

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First Hubble images of interstellar comet 3I/Atlas released

5:03 pm

Comet 3I/Atlas, taken by Hubble
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An undergraduate student has just released the first pictures taken by the Hubble Space Telescope of the interstellar object 3I/Atlas, confirming that it is a comet as indicated by the earlier image taken by the Gemini North telescope.

One of those images, taken only hours ago, is the inset on the map showing the comet’s route through the solar system to the right. The streaks on the image are either stars or cosmic rays. Though this image is of significantly lower quality than the Gemini North picture, it once again shows both the comet’s nucleus and developing coma.

A preprint [pdf] of a new research paper based on data from both telescopes further confirms this conclusion:

[T]hese results suggest that 3I/ATLAS hosts a coma containing large water ice grains, and that its dust continuum is stable over at least week-long timescales. The spectral characteristics further distinguish 3I from known ultrared trans-Neptunian objects and align it more closely with active Jupiter-family comets.

The last conclusion is very significant. Though the path and speed of this interstellar object says it must come from beyond the solar system, its cometary make-up more resembles comets that reside in the inner solar system. These facts strongly imply that there is at least one other solar systems not very different from our own.

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Astronomers detect exoplanet shaping the protoplanetary disk surrounding a baby star

9:41 am

Star with disk
Click for original image.

Astronomers using two different instruments on the Very Large Telescope (VLT) in Chile have now directly detected what they think is an exoplanet as it shapes the spiral arms of a baby star’s protoplanetary disk.

In the case of HD 135344B’s disc, swirling spiral arms had previously been detected by another team of astronomers using SPHERE (Spectro-Polarimetric High-contrast Exoplanet REsearch), an instrument on ESO’s VLT. However, none of the previous observations of this system found proof of a planet forming within the disc.

Now, with observations from the new VLT’s Enhanced Resolution Imager and Spectrograph (ERIS) instrument, the researchers say they may have found their prime suspect. The team spotted the planet candidate right at the base of one of the disc’s spiral arms, exactly where theory had predicted they might find the planet responsible for carving such a pattern.

The newly detected object however might be a brown dwarf and not an exoplanet. More observations are required to reduce the uncertainty.

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Have astronomers observed a black hole twice gobble from the same star?

9:23 am

Astronomers have now observed identical flares 700 days apart and coming from the same supermassive black hole, suggesting that a star was partially disrupted both times as it orbited the black hole.

Both flares produced less energy than predicted, based on calculations that assumed the complete destruction of a star. From the paper’s [pdf] abstract:

Here we present the optical-ultraviolet tidal disruption event AT 2022dbl, which showed a nearly identical repetition 700 days after the first flare. Ruling out gravitational lensing and two chance unrelated disruptions, we conclude that at least the first flare represents the partial disruption of a star.

…Since both flares are typical of the optical-ultraviolet class of tidal disruptions in terms of their radiated energy, temperature, luminosity, and spectral features, it follows that either the entire class are partial rather than full stellar disruptions, contrary to the prevalent assumption, or some members of the class are partial disruptions, having nearly the same observational characteristics as full disruptions. Whichever option is true, these findings could require revised models for the emission mechanisms of optical-ultraviolet tidal disruption flares and a reassessment of their expected rates.

Assuming the star wasn’t completely destroyed during the second flare, a third flare should occur about two years from now, as the star swings around and makes its next close approach. If so it will confirm this theory. If not, we will be left with the simple uncertainty of science.

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A galaxy surrounded by galaxies

11:12 am

A galaxy surrounded by galaxies
Click for original image.

Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken by the Hubble Space Telescope as part of a survey of galaxies where Type 1a supernovae have occurred, in order to better refine the precise brightness of these explosions.

What makes this galaxy most interesting are the hundreds of other galaxies that appear to surround it. And that ain’t an illusion.

NGC 3285B is a member of the Hydra I cluster, one of the largest galaxy clusters in the nearby Universe. Galaxy clusters are collections of hundreds to thousands of galaxies that are bound to one another by gravity. The Hydra I cluster is anchored by two giant elliptical galaxies at its centre. Each of these galaxies is about 150,000 light-years across, making them about 50% larger than our home galaxy, the Milky Way. NGC 3285B sits on the outskirts of its home cluster, far from the massive galaxies at the centre.

As for the survey program, Type 1a supernovae are the measure cosmologists have used to discover the unexpected acceleration of the universe’s expansion rate at the largest scales, something they dub “dark energy” because they really don’t understand what they have discovered. That discovery however hinges entirely on the assumed intrinsic brightness of Type 1a supernovae. Astronomers have assumed these supernovae all have the same approximate brightness, and extrapolate their distance by that brightness.

The problem are the assumptions. We really don’t know if all Type 1a supernovae are approximately the same brightness. And even if they are equally bright, we also do not have a firm grasp of what that brightness should be.

This survey is an attempt to narrow or eliminate these uncertainties.

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Update on eye research at ISS

10:03 am

Link here. The NASA update provides a nice overview of the research, beginning with this overview:

When astronauts began spending six months and more aboard the International Space Station, they started to notice changes in their vision. For example, many found that, as their mission progressed, they needed stronger reading glasses. Researchers studying this phenomenon identified swelling in the optic disc, which is where the optic nerve enters the retina, and flattening of the eye shape. These symptoms became known as Space-Associated Neuro-Ocular Syndrome (SANS).

The research suspects the changes are due to the fluid shifts in the body that take place due to weightlessness, with blood shifting from the legs to the head. Various projects have studied a number of solutions, including wearing leg cuffs, administering vitamin B, and possibly using centrifuge-created artificial gravity to mitigate the condition. The problem has also generated new work in developing better equipment for to studying the eye, including improved imaging and techniques for measuring the eye’s stiffness.

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Astronomers detect first evidence of gas condensing to molecular solids in baby solar system

11:39 am

Baby star with jets of new material
Click for original image.

Using a combination of ground- and space-based telescopes, astronomers have detected the first evidence of the gas and dust surrounding a young star condensing to molecular solids, thus beginning the initial stages of planet formation.

This newborn planetary system is emerging around HOPS-315, a ‘proto’ or baby star that sits some 1300 light-years away from us and is an analogue of the nascent Sun. Around such baby stars, astronomers often see discs of gas and dust known as ‘protoplanetary discs’, which are the birthplaces of new planets. … Their results show that SiO [silicon monoxide] is present around the baby star in its gaseous state, as well as within these crystalline minerals, suggesting it is only just beginning to solidify. “This process has never been seen before in a protoplanetary disc — or anywhere outside our Solar System,” says co-author Edwin Bergin, a professor at the University of Michigan, USA.

…With these data, the team determined that the chemical signals were coming from a small region of the disc around the star equivalent to the orbit of the asteroid belt around the Sun.

The false-color picture to the right, cropped, reduced, and sharpened to post here, was taken by the Atacama Large Millimeter/submillimeter Array (ALMA) telescope in Chile. It shows jets blowing out from the central baby star. Orange indicates carbon monoxide, while blue is the silicon monoxide. Initially the astronomers detected these molecules using spectroscopy from the Webb Space Telescope. This ALMA image was then used to identify where these molecules were located in the system.

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Poll: A near majority of Americans are now disgusted with the Ivy league

2:16 pm

What many now label the
A better name might be the “Poison Ivy League”

Good news: A new poll taken of 2,000 registered voters in June 2025 has found that the reputation of the Ivy League universities continues to decline, and has now dropped so much that almost half of those polled had no trust at all in these institutions.

A new poll by the Manhattan Institute found that only 15 percent of voters have a great deal of trust in the elite universities, while 46 percent have little to no trust at all.

Most of those polled said they want to see reforms such as the elimination of diversity, equity, and inclusion and race-based admissions and programs. Additionally, 64 percent “support requiring universities to advance truth over ideology by enforcing rigorous academic standards, controlling for academic fraud, requiring preregistration of scientific studies, and basing decisions on merit,” the poll found.

You can read the poll itself here. Though it covers many other major institutions, such as Congress, big business, the Presidency, public colleges and universities, it is this line item shown in the figure below that I think that stands out most starkly.
» Read more

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Scientists: The Sun’s bright corona acts to impede coronal mass ejections

10:23 am

Using data gathered by the Solar and Heliospheric Observatory (SOHO) since its launch in 1995, scientists have determined that when the Sun’s corona (its atmosphere) is bright, it acts to slow and even block the ejection of coronal mass ejections (CMEs), which if they impact the Earth’s magnetic field can have a harmful effect on our modern technology.

Using data from NRL’s Large Angle and Spectrometric Coronagraph Experiment (LASCO) on board the joint European Space Agency (ESA)-NASA Solar and Heliospheric Observatory (SOHO), the NRL team [National Research Laboratory] compiled nearly three decades of observations of the solar corona. They studied the extensive dataset to investigate trends in the brightness of the Sun’s corona and compare them to CME velocities over the same period. Their study found a strong correlation between the two datasets, with bright regions of the solar corona appearing to relate to substantially slower CME velocities and, in some cases, perhaps entirely precluding CMEs.

This data will help solar weather observers better predict the arrival of CMEs, should they erupt from the Sun aimed at Earth. It will also allow them to gauge the risk of CMEs even occurring.

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First good image released of interstellar object 3I/Atlas as it plunges through the solar system

3:25 pm

First good image of instellator object 3I/Atlas
Click for original image of 3I/Atlas.

Astronomers using the Gemini North Telescope in Hawaii have obtained the first good image of the interstellar object 3I/Atlas, as it plunges within the orbit of Jupiter on its way through the solar system.

That picture is to the right, cropped to post here and overlaid on top of a map showing the interstellar object’s calculated path through the solar system.

The picture clearly shows this is a comet, with central nucleus surrounded by a cloud of dust and gas. The data also suggests its nucleus has a diameter of about twelve miles. That it resembles a comet also suggests it is a dirty snowball, made up of ice and rocky material mixed together.

Because it will never get closer to the Sun then just inside the orbit of Mars, it is not likely it will ever get bright enough for naked eye observations. At the same time, it is large enough and will be close enough to make possible some excellent observations as it zips by and leaves the solar system sometime in the fall. The previous two identified interstellar objects, Oumuamua and Comet 21/Borisov, were either too small or too far away as they flew past to get this kind of good data.

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The failed MethaneSat climate satellite apparently had problems from launch

10:24 am

According to a detailed New Zealand news report today, the failed MethaneSat climate satellite — funded and operated by the Environmental Defense Fund — apparently had significant problems during its short fifteen month life-span, going into safe mode many times, before failing completely last month.

An earlier report from this same news outlet described more fully the issues — which began in September 2024 only about six months after launch.

The mission’s chief scientist has now said more intense solar activity because of a peak in the sun’s magnetic cycle has been causing MethaneSAT to go into safe mode. The satellite has to be carefully restarted every time.

There has also been a problem with one of the satellite’s three thrusters, which maintain its altitude and steer the spacecraft. MethaneSAT says it can operate fully on two thrusters.

It appears there is a lot of unhappiness in New Zealand for spending $32 million on this project that was designed, built, and operated by an environmental activist organization with little space experience.

What is clear now is that the spacecraft likely got relatively little data during its fifteen month life span.

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Webb spots aftermath of collision of two galaxies

10:06 am

colliding galaxies
Click for source.

Using the Webb Space Telescope, astronomers have discovered the collision of two spiral galaxies that appears to have caused a supermassive black hole to collapse in its wake.

The Webb false-color infrared image to the right shows the two galaxies as the red dots, both surrounded by a ring, with the supermassive black hole the bluish spot in between but offset somewhat to the left. Follow-up radio observations suggested that this bluish spot was a supermassive black hole, having a mass of a million suns and sucking up matter from the giant gas cloud that surrounds it.

The team proposes that the black hole formed there via the direct collapse of a gas cloud – a process that may explain some of the incredibly massive black holes Webb has found in the early universe.

This hypothesis however has enormous uncertainties, and requires a lot more observations to confirm. The black hole could simply exist unrelated to the galaxy collision, having come there from elsewhere. Or it could be from a third galaxy in this group that these initial observations have not yet detected.

The image however is quite cool.

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A distant globular cluster

10:03 am

A distant globular cluster
Click for original image.

Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken by the Hubble Space Telescope as part of a research project to study globular clusters in galaxies other than the Milky Way.

The data for this image comes from an observing programme comparing old globular clusters in nearby dwarf galaxies — the LMC [Large Magellanic Cloud], the Small Magellanic Cloud and the Fornax dwarf spheroidal galaxy — to the globular clusters in the Milky Way galaxy. Our galaxy contains over 150 of these old, spherical collections of tightly-bound stars, which have been studied in depth — especially with Hubble Space Telescope images like this one, which show them in previously-unattainable detail. Being very stable and long-lived, they act as galactic time capsules, preserving stars from the earliest stages of a galaxy’s formation.

Astronomers once thought that the stars in a globular cluster all formed together at about the same time, but study of the old globular clusters in our galaxy has uncovered multiple populations of stars with different ages. In order to use globular clusters as historical markers, we must understand how they form and where these stars of varying ages come from. This observing programme examined old globular clusters like NGC 1786 [pictured] in these external galaxies to see if they, too, contain multiple populations of stars. This research can tell us more not only about how the LMC was originally formed, but the Milky Way Galaxy, too.

This cluster, discovered in 1835 by John Herschel, is about 160,000 light years away.

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LIGO detects gravitational waves of largest black hole merger yet

9:22 am

The LIGO gravitational wave detector, spread across several continents, successfully detected the largest black hole merger yet on November 23, 2023.

The two black holes that merged were approximately 100 and 140 times the mass of the Sun. In addition to their high masses they are also rapidly spinning, making this a uniquely challenging signal to interpret and suggesting the possibility of a complex formation history. “This is the most massive black hole binary we’ve observed through gravitational waves, and it presents a real challenge to our understanding of black hole formation,” says Professor Mark Hannam, from Cardiff University and a member of the LIGO Scientific Collaboration. “Black holes this massive are forbidden through standard stellar evolution models. One possibility is that the two black holes in this binary formed through earlier mergers of smaller black holes.”

To date, approximately 300 black-hole mergers have been observed through gravitational waves, including candidates identified in the ongoing O4 run. Until now the most massive confirmed black-hole binary was the source of GW190521, with a much smaller total mass of “only” 140 times that of the sun.

As noted by the press release as well as this news article, present theories of stellar evolution say that these black holes could not have come from single stars, which are predicted to never be this massive. It is posited that each black hole might have formed from earlier mergers, but there is also a lot of uncertainty in the data. To quote the release again: “Extracting accurate information from the signal required the use of theoretical models that account for the complex dynamics of highly spinning black holes.”

That this detection was almost two years ago and only announced now makes me wonder if the timing of the announcement has more to do with lobbying and less to do with science. Trump’s proposed budget eliminates the U.S. funding portion for this project, and it is standard operating procedure for such projects to suddenly announce big discoveries timed to correspond to when Congress is considering the budget.

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Weird drainages on Mars

11:58 am

Weird drainages on Mars
Click for original image.

Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken on Februay 11, 2025 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). The camera team posted it yesterday as their own cool image, labeling it “A Fissure and Channel near Pavonis Mons”. From the caption:

A linear trough strikes northeast, then abruptly ends (or changes into a narrow ridge). Where the trough ends, a sinuous channel has an east-southeast strike, trending at almost a right angle to the trough. What happened to form these features?

We can speculate that first there was a southwest-to-northeast trending fracture or fault, perhaps associated with a volcanic vent. Groundwater (or some other runny fluid) coursed through the fault until overflowing and forming the sinuous channel. Continued movement through the fault carved a trough up to the overflow point.

The arrows indicate the downhill grades. Though this caption mentions groundwater, it is far more likely that the “runny fluid” was lava, as shown by the overview map below.
» Read more

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New census of inverted channels on Mars strongly suggests the planet once had more water

9:00 am

Martian ridges that imitate rivers
Click for original image.

A new review of inverted channels on Mars now strongly suggests that the red planet was once far wetter than presently seen, with the channels implying the existence of liquid rivers.

The discovery of more than 15,000 kilometres of ancient riverbeds on Mars suggests that the Red Planet may once have been much wetter than previously thought. Researchers looked at fluvial sinuous ridges, also known as inverted channels, across Noachis Terra – a region in Mars’ southern highlands. These are believed to have formed when sediment deposited by rivers hardened and was later exposed as the surrounding material eroded.

Similar ridges have been found across a range of terrains on Mars. Their presence suggests that flowing water was once widespread in this region of Mars, with precipitation being the most likely source of this water.

The image to the right is a good example of an inverted channel, a previous cool image posted in April 2025. It is located not in Noachis Terra but in the northern lowland plains.

The researchers argue that these channels suggest that about 3.7 billion years ago there were flowing liquid rivers on Mars, fed by precipitation. This conclusion however still does not explain how this could happen on a planet that is too cold with too thin an atmosphere for liquid water to exist. Every model so far proposed to make Mars warmer with a thicker atmosphere in the distant past remains questionable with many holes.

Could the inverted channels have been created by glacial activity, ice instead of liquid water? At present we don’t know enough about the Mars environment and the physics of such things in the planet’s one-third gravity to answer that question. It is however a question that scientists I think should be asking, based on the extensive evidence of glacial activity in the Martian mid-latitudes.

The big takeaway from this study however is that it adds weight to the overall trend seen in the data, that over time the total amount of water on the planet has declined. We can see this in glaciers, for example, with later glacial flows always falling short of previous flows. This research shows that even in the dry tropics there was once ample water, even if we don’t yet know what form it took.

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Sightseeing near Starship’s candidate Martian landing sites

2:21 pm

An interesting mesa near Starship's Martian landing zone
Click for original image.

Today’s cool image takes us sightseeing in the region on Mars that SpaceX has chosen for its prime landing zone for its Starship spaceship. The picture to the right, cropped, reduced, and sharpened to post here, was taken on May 29, 2025 by the high resolution camera on Mars Reconnaissance Orbiter (MRO), and shows a 465-foot-high unusually shaped mesa in this region.

The full resolution inset at the bottom of the picture focuses at the strange tilted layers on the southern slope of this mesa. Apparently the layers at this spot were pushed sideways so they lie significantly angled to the horizontal. Though it isn’t clear from this picture, it is possible that the mesa itself is made up of similar tilted layers, hidden below the surface. We can see the tilt only on the mesa’s southern flank because erosion has apparently exposed it.

Note also the black stain that surrounds the mesa. Though this might be caused by wind distributing dust, such stains have also been seen at a location where scientists suspect an inactive hot spring might exist, as well as another location where there may have been relatively recent volcanic activity.

Is this stain caused by any of these processes? In situ exploration would probably be necessary to find out. And we may soon actually have spaceships landing here in the relatively near future with the capability to do this.
» Read more

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Returning to Mars’ glacier country

3:21 pm

Overview map

Returning to Mars' glacier country
Click for original image.

Today’s cool image illustrates again why I rail against those who still claim Mars is dry. The picture to the right, cropped, reduced, and sharpened to post here, was taken on June 2, 2025 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).

The picture was labeled simply as a “terrain sample” by the MRO camera team, which almost always signifies that it was taken not as part of any specific science research project or by request by a scientist, but to fill a gap in the camera’s schedule in order to maintain its proper temperature. When such a gap-filler picture is required, the team tries to pick interesting features in that time frame, but don’t always succeed.

In this case, that time frame placed MRO over the northern mid-latitudes and a region I label “glacier country” because practically every picture taken in this region shows glacial features. This picture is no exception. The white dot in the overview map above marks the location, in the Protonilus Mensae area of the 2,000-mile-long strip of glaciers. The arrow in the picture itself shows the downward grade of the glacial flow. The small 2,000-foot-wide crater appears as if the impact occurred on soft ice, and the stippled terrain surrounding it appears to resemble the feature geologists have labeled “brain terrain”, a surface feature unique to Mars and associated with near surface ice, though its exact formation process is not yet understood.

Nor have I cherry-picked this image to prove my point. Its glacial-like features are very typical for this region of Mars. Note for example the inset with the larger crater to the northeast. It appears almost buried by this glacial material, which has poured through the gap in its southwest quadrant to fill it. A close look at all the low lying terrain shows similar glacial-like flows.

Mars is surely not a paradise. It is bone-chillingly cold almost all the time. Its atmosphere is so thin and lacking in oxygen you would quickly suffocate if you tried to breath it. But the data continues to suggest that the red planet has ample supplies of near-surface ice outside of its dry tropics. All future colonists will need to do is dig a bit and process the water out.

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Astronomers link fast X-ray bursts with gamma ray bursts and supernovae

1:17 pm

Using observations of a fast X-ray burst (FXT) 2.8 billion light years away by a plethora of space- and ground-based telescopes, astronomers now think the burst was caused by a massive star’s supernova explosion that would normally result in a gamma ray burst (GRB), but does not because the star’s outer layers trap the gamma rays from escaping.

Through analysis of EP 250108a’s rapidly evolving signal over the first six days following initial detection, the team found that this FXT is likely a ‘failed’ variation of a gamma-ray burst (GRB). GRBs are the most powerful explosions in the Universe and have been observed preceding supernovae. During these events, violent geysers of high-energy particles burst through a star’s outer layers as it collapses in on itself. These jets flow at nearly the speed of light and are detectable by their gamma-ray emission.

EP 250108a appears similar to a jet-driven explosion, but one in which the jets do not break through the outer layers of the dying star and instead remain trapped inside. As the stifled jets interact with the star’s outer layers, they decelerate and their kinetic energy is converted to the X-rays detected by Einstein Probe.

As always, there are many uncertainties with this conclusion.

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EPA employees who publicly signed letter opposing Trump’s agenda have now been put on leave

1:42 pm

Trump defiant after being shot
Trump in charge

They apparently forgot who the American people elected and who is thus the boss! The 170 EPA employees who publicly signed a letter this week announcing their opposition to Trump’s policies at EPA have now all been put on leave, with the expectation that they will eventually lose their jobs as well.

Staffers at the Environmental Protection Agency who signed a letter of dissent against President Donald Trump have been placed on leave, reports The Hill. “The Environmental Protection Agency has a zero-tolerance policy for career bureaucrats unlawfully undermining, sabotaging, and undercutting the administration’s agenda as voted for by the great people of this country last November,” EPA spokeswoman Brigit Hirsch said in a written statement.

The letter, posted on June 30, 2025, made it very clear in its opening paragraph that these employees were willing to defy orders and sabotage the Trump administration.
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Mars is not dry!

11:11 am

Global map of glaciers found on Mars

I once again feel compelled to rant against the shallow ignorance of too many people in both the journalism field as well as academia about the most recent data we now have of Mars. Two articles today once again show this ignorance, assuming blandly that Mars is a dry planet with little water on it anywhere, when orbital data over the past decade has unequivocally shown that — except for its equatorial regions — the planet is covered with a LOT of near-surface ice.

The headlines make this ignorance quite clear:

In both cases, the articles assume that the data obtained from rovers and landers in the dry Martian tropics applies to the entire planet. It does not. This evidence of a dry planet carries a bias that comes from the decision by the planetary community as well as NASA to send every rover to that dry equatorial region. Only one lander, Phoenix, has ever been successfully dropped far from the Martian equator, and it was purposely sent to a very high latitude, where it proved there was ice present just below the surface.

Orbital data in the past decade from both Mars Reconnaissance Orbiter and Mars Express has clearly shown that there is a lot of near surface ice on Mars, as shown by the map above. In the mid-latitudes the terrain is dominated by glaciers, as this is the region where the vast ice sheets in the high latitudes begin to fade away.

Only the equatorial region, indicated by the white lines on the map, is dry and barren. And yet, even here, orbital data has detected evidence that suggests underground ice still exists.

It seems to me that journalists and academic PR departments should know these facts, and include them in any reports about the dry nature of Mars’ equatorial regions.

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New data: the ozone hole occurs mostly because of the sunspot cycle and cosmic rays, not CFC pollution

1:18 pm

The ozone hole linked to the solar cycle

The uncertainty of science: A science paper released yesterday suggests that the ozone hole over Antarctica that scientists have been tracking for almost a half century is caused mostly by the solar cycle and the accompanying fluctuations in cosmic rays hitting the upper atmosphere, not the release of chlorofluorocarbons (CFCs) that used to be used in aerosol spray cans.

The graph to the right, from figure 2 of the paper, illustrates the data. The red line is the ozone hole fluctuations predicted by the paper’s model, labeled “CRE Theory”, based on the increase of cosmic ray radiation during solar minimum. The blue, black, and green lines indicate the actual fluctuations of ozone and temperature in the lower stratosphere where the ozone layer exists. As you can see, the model and actual fluctuations match quite closely. From the paper’s abstract:
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Sunspot update: Sunspot activity rebounds somewhat in June

12:13 pm

As I have done since I started this website fifteen years ago, I post at the start of every month an update of the Sun’s ongoing sunspot activity, using the update that NOAA posts each month to its own graph of sunspot activity but annotated by me with extra information to illustrate the larger scientific context.

Below is that graph, showing that in June sunspot activity rebounded upward somewhat from the shocking drop in activity that occurred in May.

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