Tag: science

Frozen Martian eddies at the confluence of two glacier rivers

1:46 pm

Frozen eddies at the confluence of two glacial rivers
Click for original image.

Cool image time! The picture to the right, rotated, cropped, reduced, and sharpened to post here, was taken on July 3, 2024 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).

The science team labels the photo as capturing a “contact near Reull Vallis,” a 1,000-mile-long Martian canyon that flows down the eastern slopes of Hellas Basin, the death valley of Mars.

What I see isn’t a geological contact but a complex jumble of odd-shaped depressions and mesas, surrounded by an eroded surface that seems squashed and deformed by some process. If this is all we had to go on, I would simply label this as another “What the heck?” image on Mars and move on. However, the larger context of the overview map helps explain it all, at least as best as we can explain using orbital data.
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Engineers set new laser communications record to asteroid probe Psyche

9:16 am

Psyche-Earth laser communications record
Click for original graphic.

As part of a continuing test program, engineers have set a new long distance laser communications record, exceeding 290 million miles, by successfully using a laser to send communicate with the asteroid probe Psyche from Earth.

The graph to the right, not to scale, shows the orbital configuation of the laser record. It appears however that little actual data was sent in this last test. It merely demonstrated that a link could be established. An actual data transfer record by laser occurred in June.

On June 24, when Psyche was about 240 million miles (390 million kilometers) from Earth — more than 2½ times the distance between our planet and the Sun — the project achieved a sustained downlink data rate of 6.25 megabits per second, with a maximum rate of 8.3 megabits per second. While this rate is significantly lower than the experiment’s maximum, it is far higher than what a radio frequency communications system using comparable power can achieve over that distance.

The high data rates promised by laser communications will significantly improve deep space operations. Most especially, the ability to get data back in much larger packets more quickly will reduce the antenna bottleneck on Earth that limits the number of missions as well as the data can be returned daily. More missions will be able to fly, and scientists and engineers will get their results faster.

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A new map of the magnetosphere of Mercury

12:11 pm

Map of Mercury's magnetosphere
Click for original.

Using data obtained during the June 2023 fly-by by the European-Japanese probe BepiColombo, scientists have now published a new detailed map of the magnetic field that surrounds Mercury.

That map is to the right. From the caption:

A textured sphere representing Mercury is shown with magnetic field lines compressed on the sunward side and streaming out into a tail on the nightside. The BepiColombo spacecraft’s trajectory is drawn passing through the magnetosphere from dawn to dusk, close to the planet’s surface. Various features in the magnetosphere are depicted and labelled with text. Following the order in which they were detected by the spacecraft, this includes the bow shock, magnetopause, low-latitude boundary layer, cold ion cloud, plasma sheet horn and ring current.

You can read the peer-reviewed paper here [pdf]. Note that this research does not include data obtained during BepiColumbo’s fourth fly-by of Mercury in September. Furthermore, the spacecraft will do two more fly-bys before arriving in orbit in 2026, where it will then separate into two separate orbiters in complementary orbits. Thus, this magnetic map of Mercury is merely a rough draft, and will be significantly refined by the end of the mission.

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Scientists confirm theory that thunderstorms on Earth also produce gamma ray bursts

11:42 am

Prior to the 1990s, the origin of gamma ray bursts (GRBs) was uttlerly known. First detected by satellites in the early 1970s, astronomers has no idea what caused them because without a parallel detection in optical light they had no way to determine their distance. Theories suggested the bursts could be coming from billions of light years away, from within the Milky Way, from inside the solar system, and from even the Earth’s upper atmosphere.

In the 1990s it was finally proven that GRBs almost all come from very distant cosmic events, billions of light years away, each signaling the formation of a black hole.

Now researchers have confirmed the theory that GRBs are also occuring within the Earth’s atmosphere, though these GRBs have no resemblance to the astronomical ones.

During thunderclouds, two different hard radiation phenomena have so far been known to originate: Terrestrial Gamma-ray Flashes (TGFs) and gamma-ray glows. This third phenomenon, observed and named FGFs by Østgaard et al. [2024] resembles the other two, while at the same time revealing certain characteristics separating FGFs from the others. Most noteworthy may be that FGFs are pulses of gamma-rays not associated with any detectable optical or radio signals.

“We think that FGFs could be the missing link between TGFs and gamma-ray glows, whose absence has been puzzling the atmospheric electricity community for two decades”, says lead author and Professor Nikolai Østgaard at the University of Bergen.

More information on this research can be found here. The research not only confirms the early theories as well as later detections, it adds significant nuance to the data. As noted at this second link:

“The dynamics of gamma-glowing thunderclouds starkly contradicts the former quasi-stationary picture of glows, and rather resembles that of a huge gamma-glowing boiling pot both in pattern and behavior,” said Martino Marisaldi, professor of physics and technology at the University of Bergen.

Given the size of a typical thunderstorm in the tropics, which get much larger than storms at other latitudes, this suggests that more than half of all thunderstorms in the tropics are radioactive. The researchers postulate that this low-level production of gamma radiation acts like steam boiling off a pot of water and limits how much energy can be built up inside.

This data will help refined the computer models that attempt to predict weather patterns, as it appears the phenomenon impacts the formation of thunderstorms.

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Water on the Moon? New data analysis from two different lunar orbiters say yes

10:04 am

Two papers in the past month using data from two different lunar orbiters have claimed the presence of water on Moon, based on the detection of evidence of hydrogen on the surface.

First, on September 16, 2024 scientists published a paper [pdf] that analyzed data collected in 2009 by India’s Chandrayaan-1 lunar orbiter, and concluded, as stated enthusiastically in the press release:

Map of permanently shadowed regions at the Moon's south pole
From the second paper, a map of permanently shadowed
regions at the Moon’s south pole. Click for original.

“Future astronauts may be able to find water even near the equator by exploiting these water-rich areas. Previously, it was thought that only the polar region, and in particular, the deeply shadowed craters at the poles were where water could be found in abundance,” said Roger Clark, Senior Scientist at the Planetary Science Institute and lead author of “The Global Distribution of Water and Hydroxyl on the Moon as Seen by the Moon Mineralogy Mapper (M3)” that appears in the Planetary Science Journal. “Knowing where water is located not only helps to understand lunar geologic history, but also where astronauts may find water in the future.”

Then today NASA announced the publication of a new paper [pdf] that looked at the data collected over the last decade by Lunar Reconnaissance Orbiter (LRO), and have concluded that “hydrogen-bearing volatiles are observed to be concentrated, likely in the form of water ice, within most of the Moon’s permanently shadowed regions (PSRs), poleward of 77°.” The press release, which included the map to the right of permanently shadowed areas at the Moon’s south pole, was more enthusiastic:
» Read more

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Viewing Comet Tsuchinshan-ATLAS

9:02 am

While the newly discovered Comet Tsuchinshan-ATLAS in the past week reached naked eye visibility in the dawn sky, in the next few weeks it will shift into the evening sky on October 11, 2024 while brightening to peak levels.

Although Comet Tsuchinshan-ATLAS will be visible in both hemispheres, the northern one is favored because the comet tracks north. Also, sunsets are getting earlier and twilights shorter, while the opposite is happening in southern latitudes.

Observers should be aware that the Moon will interfere for several nights, from about Oct. 15-20 (full Moon is on Oct. 17th), around the same time the comet climbs out of twilight.

As it begins to fade, the comet will be visible at an increasing height above the horizon each night through the end of October. At its brightest it is expected to be one of the brightest objects in the sky.

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Sunspot update: Sunspot activity crashes in September

3:56 pm

As it is the start of the month, it is time another monthly sunspot update, in which I provide some context and analysis to NOAA’s most recent update of its monthly graph tracking the number of sunspots on the Sun’s Earth-facing hemisphere.

After several months in which the number of sunspots rose considerably each month, in September the sunspot count crashed, dropping precipitously to levels closer to the various predictions of solar scientists, but still far above what they had all expected at this time of the solar maximum.

» Read more

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The strange terrain of the Martian southern ice cap

12:13 pm

The strange terrain of Mars' south pole
Click for original image.

Cool image time! The picture to the right, rotated, cropped, and sharpened to post here, was taken on July 29, 2024 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows a section at the Martian south pole at the very high latitude of 87 degrees south, only about 100 miles from the pole itself.

The label for this picture is “possible water ice and mesas,” suggesting we are looking at an ice cap of water that is partly sublimated away.

In truth, things are much more complicated. It was summer when this photo was taken. Note the drainage in the lower right and the dark spidery lines there. In the winter on Mars atmospheric carbon dioxide falls as snow and coats the poles to about 60 degrees latitude with a thin mantle of dry ice. In the spring this mantle sublimates away, but does so in an counter-intuitive manner. The sublimation first occurs at the mantle’s base, and the trapped gas flows up until it finds a weak spot in the mantle and cracks through, spewing out and deposting dark splotches of dust.

At the south pole this upward flow always follows the same paths, producing the dark spidery patterns we see here. In the case of the drainage in the lower right, this is a drainage of gas eastward until it pops out at the slope, causing that depression to become darkly stained.

This is only part of the story of this complex geology, however.
» Read more

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Scientists detect jets of carbon dioxide and carbon monoxide from asteroid

9:45 am

Jets from asteroid
Click for original graphic.

Using the spectroscopy from the Webb Space Telescope, scientists have now detected jets of carbon dioxide and carbon monoxide spewing from the very active asteroid 29P/Schwassmann-Wachmann-1 (29P).

Based on the data gathered by Webb, the team created a 3D model of the jets to understand their orientation and origin. They found through their modeling efforts that the jets were emitted from different regions on the centaur’s nucleus, even though the nucleus itself cannot be resolved by Webb. The jets’ angles suggest the possibility that the nucleus may be an aggregate of distinct objects with different compositions; however, other scenarios can’t yet be excluded.

The graphic to the right illustrates the modeling of these jets. That the center of this two-lobed asteroid could have been created from distinct objects suggests a very complex formation process, since those objects would have had to have formed themselves in different locations in the solar system and then somehow come together.

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Carbon dioxide and hydrogen peroxide found on the surface of Pluto’s moon Charon

9:03 am

Using spectroscopic data from the Webb Space Telescope, scientists have detected both carbon dioxide and hydrogen peroxide on the surface of Pluto’s moon Charon, adding these chemicals to the previously detected water ice and ammonia-bearing chemicals that give the planet its gray and red colors.

The team compared the spectroscopic observations with laboratory measurements and detailed spectral models of the surface, concluding that carbon dioxide is present primarily as a surface veneer on a water ice-rich subsurface. “Our preferred interpretation is that the upper layer of carbon dioxide originates from the interior and has been exposed to the surface through cratering events. Carbon dioxide is known to be present in regions of the protoplanetary disk from which the Pluto system formed,” Protopapa said.

The presence of hydrogen peroxide on the surface of Charon clearly indicates that the water ice-rich surface is altered by solar ultraviolet light and energetic particles from the solar wind and galactic cosmic rays. Hydrogen peroxide forms from oxygen and hydrogen atoms originating from the breakup of water ice due to incoming ions, electrons or photons.

The theory proposing the dry ice comes from the interior is interesting, but there simply is not enough data to take it very seriously at this point.

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Astronomers detect exoplanet half as massive as the Earth around second closest star system

11:28 am

Using the Very Large Telescope (VLT) in Chile, astronomers have detected evidence of an exoplanet about half as massive as the Earth orbiting Barnard’s Star, only six light years away and the second closest star system.

Barnard’s Star is a prime target in the search for exoplanets due to its proximity and its status as a red dwarf, a common type of star where low-mass planets are often found. Despite a promising signal detected in 2018, no planet had been definitively confirmed around it until now. The ESPRESSO spectrograph [on VLT] … enabled the astronomers to detect Barnard b, a subterrestrial planet that orbits the star in 3.15 days. The team also identified signals indicating the possible presence of three other candidate exoplanets, which have yet to be confirmed.

Back in the 1960s using the less precise instruments of the time, astronomers thought they had detected an exoplanet orbiting Barnard’s Star. That detection however proved false. The detection is real, however, and adds weight to the growing evidence that planets can form around red dwarf stars, the most common stars in the universe with the longest lifespan, predicted to be many tens of billions of years. Having planets around such stars significantly increases the chances of habitable planets, even if those planets do not harbor life of its own.

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Data from two different studies suggest Betelgeuse has a Sun-sized companion star

9:46 am

Betelqeuse
An optical image of Betelgeuse taken in 2017 by a ground-based
telescope, showing its not unusual aspherical shape.
Click for original image.

Two different independent studies have uncovered evidence that the red giant star Betalgeuse likely has an unseen companion star about the mass of the Sun and orbiting it every six years.

MacLeod and colleagues linked a six-year cycle of Betelgeuse brightening and dimming to a companion star tweaking its orbit, in a paper submitted to arXiv.org September 17. MacLeod examined global, historical measurements dating back to 1896.

Separately, Jared Goldberg of the Flatiron Institute in New York and colleagues used the last 20-odd years of measurements of Betelgeuse’s motion on the sky, which have the highest precision. That team also found evidence of a companion nudging the bigger star, submitted to arXiv.org August 17.

Previous observers noticed Betelgeuse’s light varying on a roughly six-year cycle. In 1908, English astronomer Henry Cozier Plummer suggested the cycle could be from the gravity of a companion star tugging Betelgeuse back and forth.

You can download the two papers here and here. This quote from the first paper’s abstract not only explains why the star has not been detected previously, but suggests its doomed future:

The companion star would be nearly twenty times less massive and a million times fainter than Betelgeuse, with similar effective temperature, effectively hiding it in plain sight near one of the best-studied stars in the night sky. The astrometric data favor an edge-on binary with orbital plane aligned with Betelgeuse’s measured spin axis. Tidal spin-orbit interaction drains angular momentum from the orbit and spins up Betelgeuse, explaining the spin–orbit alignment and Betelgeuse’s anomalously rapid spin. In the future, the orbit will decay until the companion is swallowed by Betelgeuse in the next 10,000 years. [emphasis mine]

The presence and future capture of this small companion star will help astronomers better calculate future fluctuations of Betelgesue itself. That capture is also going to occur relatively soon, on astronomical time scales.

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During fly-by Juice snaps picture of Earth’s radiation belts

9:32 am

Juice image of Earth's radiation belts
Click for original graphic.

During its fly-by of Earth on August 19-20, the European Jupiter orbiter Juice used its NASA instruments, designed to study the radiation environment around the gas giant, to snap a false color image of the Earth’s radiation belts, as shown in the graphic to the right. From the caption:

On Aug. 19, JENI and its companion particle instrument Jovian Energetic Electrons (JoEE) made the most of their brief 30-minute encounter with the Moon. As Juice zoomed just 465 miles (750 kilometers) above the lunar surface, the instruments gathered data on the space environment’s interaction with our nearest celestial companion. It’s an interaction scientists expect to see magnified at Jupiter’s moons, as the gas giant’s radiation-rich magnetosphere barrels over them.

On Aug. 20, Juice hurled into Earth’s magnetosphere, passing some 37,000 miles (60,000 km) above the Pacific Ocean, where the instruments got their first taste of the harsh environment that awaits at Jupiter. Racing through the magnetotail, JoEE and JENI encountered the dense, lower-energy plasma characteristic of this region before plunging into the heart of the radiation belts. There, the instruments measured the million-degree plasma encircling Earth to investigate the secrets of plasma heating that are known to fuel dramatic phenomena in planetary magnetospheres.

The dotted line shows the trajectory of ESA’s Juice spacecraft during its lunar-Earth gravity assist, with the white rings indicating equatorial distances of 4 and 6 Earth radii. The colors indicate the strength of the energetic neutral atoms detected by the instruments, and show the million-degree hot plasma halo that circles the Earth.

The data proved that the instruments are functioning as intended, and will thus be able to achieve their main goal, studying the much more active and energetic radiation belts of Jupiter.

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Perseverance looks uphill

9:51 am

Perseverance looks uphill
Click for full resolution. The original images can be found here and here.

Cool image time! The panorama above was created by me from two pictures taken today by the left navigation camera on the Mars rover Perseverance (found here and here). The haziness in the air is the left over from a local dust storm in Jezero Crater during the past month.

On the overview map below, the blue dot marks Perseverance’s present position, with the red dotted line indicating the approximate planned route of the rover uphill. The yellow lines are my guess as to the area covered by the panorama above. That guess could be wrong, as not all the features in the picture match the overview map. The view could be much closer, with the hill and ridgeline nothing more than the small outcrops close to the rover.

Nonetheless, these navigation pictures show us the kind of terrain the rover will be climbing as it works its way up the rim of Jezero Crater. The ground is relative smooth, though steep. My guess is that this is about a 25% grade, which on Earth would be a problem but on Mars it is a grade that NASA’s other rover, Curiosity, has routinely traversed. Perseverance has not yet traveled this kind of steepness, but there is no reason to expect it to have any difficulties doing so.

Overview map
Click for interactive map.

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Curiosity spots a corroded weathered rock

9:15 am

a weathered and corroded rock
Click for original image.

Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken on September 29, 2024 by the close-up camera mounted at the end of the robot arm of the rover Curiosity on Mars.

This is a small rock, less than three inches across. It is embedded in the sand and soil of Mars, its surface clearly weathered and smoothed by some process. The holes and gaps in the rock could have occurred prior to that smoothing, getting exposed by it. Or possibly the holes developed during the smoothing, with sections breaking off because the material was like sandstone, easily friable.

What caused the smoothing? The data from Curiosity as it climbs Mount Sharp suggests some water process, either flowing water or glacial ice. The scientists at present tend to prefer the liquid explanation, but that requires the Martian atmosphere to have once been much thicker and warmer, conditions that no model has yet demonstrated convincingly was ever possible.

The rock is also likely another example of sulfur, part of the sulfate-bearing unit of geology that Curiosity is presently traversing.

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Crazy swirling Martian landscape

1:48 pm

Crazy swirling Martian landscape
Click for original image.

Cool image time! The picture to the right, cropped, reduced, sharpened, and annotated to post here, was taken on July 1, 2024 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).

The science team labels this “Contacts between Likely Sulfates and Chaos Blocks.” That contact I have indicated with the dotted line. To the west the lighter terrain is likely the sulfate-bearing unit, similar to the sulfate-bearing unit that Curiosity has been traversing on Mount Sharp for the past year or so.

To the east are the chaos blocks, but I think that description is wholly inadequate. In truth, I haven’t the faintest idea how this terrain got to be the way it is. It is evident that a lot of dust and sand has gotten trapped in the hollows, leaving behind ripple dunes in some places, but why the higher ridges swirl and curve about as they do is utterly baffling.
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Scientists locate lunar impact crater produced by LCROSS in 2009

11:07 am

Figure 2 of research paper
Taken from figure 2 of the paper. Click for
original image.

Using orbital radar and opitcal images scientists finally believe they have identified the small crater on the Moon produced when — as part of the 2009 LCROSS mission — an abandoned rocket stage crashed in a permanently shadowed section of Cabeus crater near the lunar south pole.

LCROSS was designed to study the ejecta thrown up by that impact, and found “a significant amount of water, estimated at 5.6 ± 2.9% by mass, as well as minor amounts of other volatile species.” Because the impact was in that permanently shadowed region, however, locating the new crater required new instrumentation.

Using a radar instrument on Lunar Reconnaissance Orbiter (LRO) as well as the Shadowcam instrument on South Korea’s Danuri orbiter — designed to take optical images in very low light — the scientists pinpointed that impact crater, as shown in the image to the right, overlaying both the radar and optical images. The crater is estimated to be about 22 meters across, about 25% smaller than predicted. From this the scientists conclude that the water in the ejecta plume came from close to the surface, and thus could only have been placed there in the past billion years. Before that, the location was not in shadow, and volatiles like water could not have survived if they were near the surface.

From this data the scientists believe the water was likely placed there by the “recent delivery by comets or the solar wind, rather than as a paleo-reservoir from an early volcanic atmosphere.” If so, the amount of material can be reasonably predicted, and is likely less than hoped for because it only exists in the top two meters.

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Rocket Lab completes new capsule for Varda

9:10 am

Varda's space capsule, on the ground in Utah
Varda’s first capsule on the ground in Utah.

Rocket Lab today announced it has completed testing and intergration of a new recoverable capsule for the in-space manufacturing company Varda, to be used in orbit to produce pharmaceuticals that can only be created in weightlessness.

No launch date was announced. This was the second of four capsules Rocket Lab is building for Varda, with the first having already completed its flight, where it returned to Earth after successfully crystallizng the HIV drug Ritonavir.

The most important tidbit in the press release however was this:

Varda received permission from the FAA under a Part 450 license earlier this month, making them the only company to ever secure a second reentry license.

With the first capsule, the capsule’s return was delayed almost six months because the FAA and the military couldn’t get their paperwork together to approve the return license. Varda now has that return license in hand before launch, meaning it will get the capsule back when it wants.

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The jet 3,000 light years long that causes nearby stars to explode

10:48 am

The jet from M87
Click for original image.

Cool image time! The picture to the left, cropped, reduced, and sharpened to post here, was taken by the Hubble Space Telescope of the giant eliptical galaxy M87, known for more than a century by astronomers for the jet of gas that points outward from its center. Astronomers now know that this jet is produced by a supermassive black hole in the center of M87, weighing 6.5 billion times the mass of our Sun.

The blowtorch-like jet seems to cause stars to erupt along its trajectory. These novae are not caught inside the jet, but are apparently in a dangerous neighbourhood nearby. During a recent 9-month survey, astronomers using Hubble found twice as many of these novae going off near the jet as elsewhere in the galaxy. The galaxy is the home of several trillion stars and thousands of star-like globular star clusters.

M87 is considered an old galaxy, but its entire formation process remains uncertain.

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The mess that presently exists in science

10:16 am

Lysenko with Stalin
Trofim Lysenko (on the left), preaching to Stalin as he destroyed
Soviet plant research by persecuting anyone who disagreed with him,
and caused famines that killed millions.

Two stories today in the peer-review journal Science illustrate bluntly the dry rot that has seeped into the entire peer-review scientific community, much of it caused by the politics and incompetence that always follows when too much government money is available to hand out.

In the first story, Science simply provided a horrifying overall summary of the misconduct and research fakery committed by Eliezer Masliah, who as head of the the Division of Neuroscience at the National Institute of Aging (NIA) beginning in 2016 was crucial in recommending who would get major grants for doing research into diseases like Alzheimer’s.

Masliah’s own published peer-reviewed research into Alzheimer’s helped guide him in awarding grants. His work had said that proteins found in brain tissue were a major factor in causing the disease, and thus based on his recommendations for the next decade huge amounts of money were devoted to following up that conclusion.

The problem was that Masliah’s work was garbage.
» Read more

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Monitoring gullies on Mars for changes

12:25 pm

Overview map

Monitoring gullies on Mars
Click for original image.

Cool image time! The picture to the right, cropped, reduced, and enhanced to post here, was taken on June 29, 2024 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). The scientists label the picture simply as “gully monitoring,” with an apparent goal of looking to see if this gully has changed since MRO took the first high resolution image two years previously. In the interim this terrain went from Martian spring, through summer and winter, and has now returned to spring.

As far as I can tell, no changes are visible, but then I am not using the highest resolution data available. Small changes might be detectable in the highest resolution using good detection software. Overall, the gully drops about 3,000 feet.

The white dot in the overview map above marks the location, on the southwest interior rim of an unnamed 30-mile wide crater. This region in the Martian cratered highlands was featured in a four part cool image series I did back 2023 (here, here, here, and here), with this as my conclusion:

Overall, our short survey of the southern cratered highlands suggests that the glacial material and ice found in the southern mid-latitudes affects the Martian surface differently than in the northern lowland plains. In the north the craters and the surrounding terrain often appear blobby, as if the ice is close to the surface and also a dominant component of the ground. Impacts therefore cause significant soft melt features, with craters often heavily distorted. Similarly, there is evidence of the existence of past mud volcanoes that once spewed water and mud from below ground.

In the south however the surface is at a higher elevation, and it appears the ice layer is deeper underground. Thus, it appears the ground is more firm, and the only obvious evidence of an underground layer of ice is revealed when sublimation and the subsequent erosion produce these large pits inside craters.

In the case of this crater, a small impact on its interior southwest slope apparently caused that underground layer of ice to melt temporarily and flow downhill, leaving behind the gully and flow features we see today. Based on the two MRO pictures taken a full Martian year apart, it appears the feature is generally stable and thus likely old, left over from that impact. If things are changing seasonally they are doing so in small amounts and slowly.

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Researchers identify the oldest cheese so far found, from 3,600 years ago

10:01 am

One of the ancient cheese samples
Click for full image, figure 1 from the paper.

Researchers have confirmed that three clumps of organic matter taken from a gravesite in northwestern China are the oldest samples of cheese yet identified — more than 3,600 years old — and are in fact a specific kind of cheese, called kefir cheese.

And it’s not just any cheese: Cow and goat DNA, as well as the bacterium Lactobacillus kefiranofaciens, has indicated that these clumps were in fact kefir cheese, providing insight into the history and evolution of probiotics and human health. L. kefiranofaciens is still a key microorganism in kefir soft cheeses. The researchers also identified the microscopic fungal species Pichia kudriavzevii, which is a type of yeast found in kefir grains today.

These kefir grains contain a host of probiotic bacteria and yeast, which is key in fermenting milk to produce kefir products that have been studied for their health impacts, particularly in the areas of the immune and gastrointestinal systems, as well as metabolic regulation.

“Our observation suggests kefir culture has been maintained in Northwestern China’s Xinjiang region since the Bronze Age,” Fu said.

You can read the published paper here. The researchers suggest the cheese indicates not only the evolutionary history by which humans began creating such diary products, it also suggests the historical routes this process followed across the European and Asian continents.

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A puzzling striped rock on Mars

9:32 am

A striped rock on Mars
Click for original image.

Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken on September 13, 2024 by one of the high resolution cameras on the Mars rover Perseverance. The rock’s striped nature makes it unique, unlike any feature spotted by any rover previously. From an update today:

The science team thinks that this rock has a texture unlike any seen in Jezero Crater before, and perhaps all of Mars. Our knowledge of its chemical composition is limited, but early interpretations are that igneous and/or metamorphic processes could have created its stripes. Since Freya Castle [the name the science team gave the rock] is a loose stone that is clearly different from the underlying bedrock, it has likely arrived here from someplace else, perhaps having rolled downhill from a source higher up. This possibility has us excited, and we hope that as we continue to drive uphill, Perseverance will encounter an outcrop of this new rock type so that more detailed measurements can be acquired.

Without doubt the rock’s rounded surface suggests it was ground smooth by either water or ice. That surface certainly resembles glacial cobble seen across the northeast of the U.S. where ice glaciers once covered the entire landscape. The rock also resembles river cobble, smoothed by flowing water.

The stripes however suggest that prior to its being smoothed, this rock underwent a much more complex geological process, whereby two different materials were intermixed and squeezed together.

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Layered mesas in Martian chaos

12:27 pm

Layered mesas in Martian chaos
Click for original image.

Cool image time! The picture to the right, rotated, cropped, reduced, and sharpened to post here, was taken on May 19, 2024 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows a 2,500 to 3,000-foot-high mesa with what the scientists call “bedrock layers”, most obvious as the lower terraces on the mesa’s western slopes.

What makes this mesa especially interesting is its overall shape. It appears as if something has taken a bite out of it, resulting in that bowl-like hollow on the mesa’s southern half.

Was this caused by an impact? Or has some other long term Martian processes caused it?

This mesa is just one of many mesas in a region of chaos terrain dubbed Hydraotes Chaos. Such chaos terrain is thought to form when erosion processes, possibly glacial in nature, that carve out canyons along faultlines, leaving behind mesas with randomly oriented canyons cutting in many directions.
» Read more

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Observations of solar flares do not match the standard model used to explain their origin

9:47 am

The uncertainty of science: When scientists carefully compared new and much more precise observations of the Sun’s solar flares with the standard model they have used for decades to explain their origin, they found unexpected differences, suggesting the model is wrong or imcomplete.

In sum, none of the processes simulated in accordance with the model proved capable of explaining the observational data. The conclusion drawn by the researchers was obvious to some extent: the standard model of solar flares needs to be reformulated, as required by the scientific method.

The scientists found that the two sources of each flare brightened at slightly different times. The model said these sources should brighten almost simulatanously, and no version of the model could explain the contradiction.

All this means is that the researchers simply don’t have enough data or understanding of the Sun to formulate a model that can fully explain the process. This study simply demonstrates this, but also provides a guide for soliving the problem.

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Bioengineered heart samples on ISS confirm that weightlessness weakens and ages the heart

9:33 am

Using 48 bioengineered heart samples that spent 30 days on ISS in 2020, scientists have confirmed other research that showed weightlessness not only weakens the heart, it ages it as well.

In addition to losing strength, the heart muscle tissues in space developed irregular beating (arrhythmias)—disruptions that can cause a human heart to fail. Normally, the time between one beat of cardiac tissue and the next is about a second. This measure, in the tissues aboard the space station, grew to be nearly five times longer than those on Earth, although the time between beats returned nearly to normal when the tissues returned to Earth.

The scientists also found, in the tissues that went to space, that sarcomeres—the protein bundles in muscle cells that help them contract—became shorter and more disordered, a hallmark of human heart disease. In addition, energy-producing mitochondria in the space-bound cells grew larger, rounder and lost the characteristic folds that help the cells use and produce energy.

Finally …[t]he tissues at the space station showed increased gene production involved in inflammation and oxidative damage, also hallmarks of heart disease.

None of this is ground-breaking, as it confirms numerous other past studies. What it does do however is confirm that long-term weightlessness is not good for a person’s heart. Many studies have shown that these issues mostly go away once astronauts return to Earth, but for any journey to Mars, involving two years in weightlessness, this data suggests the health risks will be far higher.

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More deterioration to Curiosity’s worst wheel

12:13 pm

Comparison of changing damage from Feb to Sept 2024
For original images go here, here, and here.

The science team for the Curiosity Mars rover on September 22, 2024 did another survey of its damaged wheels using the close-up camera on the end of the rover’s arm, and though most of the pictures appear to show the situation remains stable, the one wheel that has consistently shown the worst damage now shows some additional deterioration since February 2024.

To the right are comparison pictures, with the February 2024 picture on top and two new September 22, 2024 images showing the same damaged area, though from a different angle, on the bottom. (The technical captions for the bottom images can be found here and here.) I have labeled the treads, dubbed growsers, to make it easier to understand how the pictures all line up.

Previous images have looked down at the large damaged area from growsers 1 to 4, and since it was first spotted in 2022 showed it to be growing, but very slowly. The new pictures show that same damaged area from the side, which reveals that the zig-zag divider between growser #3 and growser #4 has now collapsed, so that this whole damaged area is now a major depression, as indicated by the two arrows.

Overall, the rover’s wheels appear to surviving the rough terrain of the foothills of Mount Sharp, though it is clear that care must continue to be taken to extend their life for as long as possible. That the rover has six wheels gives it a lot of redundancy, so that even if this one wheel eventually fails the rover will likely be able to continue to rove, but with some limitations. This wheel is the left middle wheel, which is helpful, as it is less necessary than the four corner wheels. [Update: According to a rover update today, this wheel is the right middle wheel, which contradicts an earlier report which described this as the left middle wheel. I note this contradiction for accuracy.]

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Land of cracks

1:26 pm

Land of cracks

Cool image time! The picture to the right, cropped to post here, was taken on June 28, 2024 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). Labeled a “terrain sample,” it was likely taken not as part of any specific research project but to fill a gap in the camera’s schedule in order to maintain its proper temperature. When the camera team needs to do this, they try to pick something interesting, but don’t always have that option.

In this case, the landscape available included the channel shown to the right. About a half mile wide and only about fifty feet deep, the floor of this canyon appears to have a lot of trapped dust, forming ripple dunes, along with a lot of knobby protrusions, likely small mesas. The canyon walls appear layered, with the erosion processes producing different features on opposite sides. On the southeast the layers appear to produce distinct terraces, while on the northwest the cliff is very steep at the top and then forms a long gently descending slope that appears formed of alluvial fill (from that cliff) and formed from erosion and landslides.
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SpaceX finds a way to extend the launch window for Europa Clipper

10:03 am

The launch window for SpaceX’s launch of NASA’s Europa Clipper to Jupiter has now been extended a full week because the company has revised the launch process and made hardware changes.

The new launch window runs from October 10th to November 6th.

Usually the two side boosters come back to land at Cape Canaveral Space Force Station so they can be reused and sometimes the core booster is recovered at sea, but not this time. All their fuel will be used to get Europa Clipper on its way to Jupiter. Piloto said SpaceX “made some hardware modifications that enable the launch vehicle to utilize all the fuel in the boosters,” but couldn’t go into detail about what they are because the information is proprietary.

[The NASA official] added that SpaceX has gained experience in flying this configuration — it’s the 11th Falcon Heavy launch — and the company has “come up with a strategy to optimize throttling of the launch vehicle to get more performance out of it.”

NASA and SpaceX have also decided to use NASA’s orbiting communications constellation during the launch instead of ground stations, which increases their flexibility and margins.

I wonder if the FAA has approved these changes. Or even if anyone there even understands them.

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Webb takes an infrared look at a galaxy looked at by Hubble

12:21 pm

Comparing Hubble with Webb
For original images go here and here.

Cool image time! The bottom picture on the right, cropped to post here, is a just released false color infrared image of the galaxy Arp 107, taken by the Webb Space Telescope. The picture at the top is a previously released optical image taken by the Hubble Space Telescope and featured as a cool image back in September 2023. The Hubble image was taken as part of a survey project to photograph the entire Arp catalog of 338 “peculiar galaxies,” put together by astronomer Halton Arp in 1966. In this case Arp 107 is peculiar because it is actually two galaxies in the process of merging. It is also peculiar because the galaxy on the left has an active galactic nuclei (AGN), where a supermassive black hole is sucking up material and thus emitting a lot of energy.

The Webb infrared image was taken to supplement that optical image. The blue spiral arms indicate dust and star-forming regions. The bright orange object in the center of the galaxy is that AGN, clearly defined by Webb’s infrared camera.

When I posted the Hubble image in 2023, I noted that “if you ignore the blue whorls of the left galaxy, the two bright cores of these merging galaxies are about the same size.” In the Webb image the two cores still appear about the same size, but in the infrared they produce emissions in decidedly different wavelengths, as shown by the different false colors of orange and blue. The core of the galaxy on the right is dust filled and forming stars, while the core of the left galaxy appears to have less dust with all of its emissions resulting from the energy produced by the material being pulled into the supermassive black hole.

The universe is very active and changing, but to understand that process we humans have to look at everything across the entire electromagnetic spectrum, not just in the optical wavelengths our eyes see.

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