Tag: science

Archaeologists discover 35 glass jars at Mount Vernon from 1700s, most containing edible preserved fruits

11:31 am

During an on-going renovation at George Washington’s Mount Vernon home, archaeologists have discovered 35 glass jars from the 1700s, with most containing preserved cherries and berries that appear completely edible.

Of the 35 bottles, 29 are intact and contain perfectly preserved cherries and berries, likely gooseberries or currants. The contents of each bottle have been carefully extracted, are under refrigeration at Mount Vernon, and will undergo scientific analysis. The bottles are slowly drying in the Mount Vernon archaeology lab and will be sent off-site for conservation.

Only a small quantity of the preserved fruits has been analyzed, with the following results:

  • 54 cherry pits and 23 stems have been identified thus far, suggesting that the bottles were likely full of cherries before bottling. Cherry pulp is also present.
  • Microscopy suggests that the cherries may have been harvested by snipping from trees with shears. The stems were neatly cut and purposefully left attached to the fruit before bottling.
  • The cherries likely are of a tart variety, which has a more acidic composition that may have aided in preservation.
  • The cherries are likely candidates for DNA extraction, which could be compared against a database of heirloom varieties to determine the precise species.
  • The pits are undergoing an examination to determine if any are viable for germination.

The last point is most fascinating. Imagine if a new cherry tree could be grown from a pit that was likely picked when George Washington was alive.

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Perseverance looks back at downstream Neretva Vallis

9:58 am

Perseverance looks backwards
Click for full resolution version. Highly recommended!

Cool image time! The panorama above was released today by the science team of the Mars rover Perseverance, created from 56 pictures taken by the rover’s high resolution camera. It looks east, downstream into Neretva Vallis, what is believed to be the ancient riverbed that produced the delta that now exists inside Jezero Crater.

The yellow lines in the overview map below indicate the approximate area shown by the panorama. The blue dot marks where Perseverance was located when it took these pictures on May 17, 2024.

Make sure you look at the full resolution image. Neretva Vallis, the depression in the center of the panorama, is about a quarter-mile wide. The green dot on the map marks Ingenuity’s final landing spot. Though the helicopter is somewhere inside that panorama, it does not appear to be visible as it lies on the far side of one of those dunes.

It is also possible that Ingenuity is visible, but is only a tiny dark dot that makes it hard to identify. In reviewing the high resolution image closely, there is one dot that could be Ingenuity.

Overview map
Click for interactive map.

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Study: Dust removal at Jezero 9x greater than InSight landing area

11:41 am

Figure 2 from the paper
Figure 2 from the paper. Click for original.

Using data from the Mars rover Perseverance, scientists have concluded that dust removal rate in Jezero crater is almost ten times greater than where InSight landed in western Elysium Planitia.

The graph, figure 2 from their paper, illustrates that differents starkly. From their abstract:

Dust removal is almost 10 times larger than at InSight’s location: projections indicate that surfaces at Jezero will be periodically partially cleaned. The estimations of the effect of the accumulated dust as a function of time are encouraging for solar-powered missions to regions with similar amounts of dust lifting, which might be determined from orbital data on where dust storms originate, dust devils or their tracks are found, or seasonal albedo changes are noted.

In other words, it might be practical to send solar powered rovers to different places on Mars, if first research was done to see if the conditions there would regularly clear dust from those panels.

This research confirms what had been implied by the different experiences of landers/rovers in different places on Mars. InSight landed near the equator in a region south of the giant shield volcano Elysium Mons. It only survived four years, with steadily lower energy levels, because no wind or dust devil ever cleared the accumulating dust on its solar panels. Spirit meanwhile landed about 1,500 miles southwest of InSight, yet its power levels were still healthy after more than five years of operations, when those operations ended because the rover could no longer move. The rover Opportunity meanwhile on the other side of the planet lasted more than fourteen years. Both rovers relied on solar power, like InSight, but their solar panels kept getting cleared of dust by wind and dust devils.

It is unclear if this wind research has been done for Europe’s Franklin rover, presently scheduled to land in Oxia Planum in 2028. Franklin will rely on solar panels, and though its nominal mission on the surface is only supposed to last seven months, it is always assumed it will continue until the rover fails.

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Perseverance looks up at the rim of Jezero Crater

1:01 pm

Panorama on June 10, 2024 by Perseverance
Click for full resolution. For original images, go here, here, here, and here.

Overview map
Click for interactive map.

Cool image time. The panorama above was created from four pictures taken on June 10, 2024 by the left navigation camera on the Mars rover Perseverance (captions found here, here, here, and here). It looks north at the nearest hill that forms the north part of the rim of Jezero Crater.

The overview map to the right provides context. The blue dot marks Perseverance’s present location, when it took these pictures. The yellow lines indicate the approximate area covered by the panorama. The red dotted line marks the rover’s planned route, while the white dotted line the route it has actually taken.

Because the rover is now at the base of this hill, it can no longer see the top of the crater’s rim. What it sees instead is the barren foothills of that rim, covered with dust, dunes, and many broken rocks.

As I have noted numerous times, the utter lack of life marks this as a truly alien landscape, compared to Earth. Nowhere on our home planet would you see terrain this empty of life. While NASA likes to claim that Perseverance’s main mission is the search for life on Mars, that claim is always a lie. It is very unlikely any life is going to be found here by Perseverance, and if that was its true scientific purpose it would never have been built nor launched.

What the scientists are doing is studying the alien geology of Mars, to try to understand how this utterly alien planet got to be the way it is now. Such knowledge is critical for the future explorers of space, as it will make it easier for them to understand the alien landscapes they will find elsewhere, within the solar system and eventually in other solar systems far beyond.

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Curiosity sees evidence of solar storm hitting Mars

12:11 pm

Charged particles from solar storm
Click to see original three-frame movie.

Cool image time! The picture to the right is a screen capture from a three-frame movie created from photos taken by one of the navigation cameras on the Mars rover Curiosity. The white streak and other smaller streaks were created by charged particles hitting the camera’s CCD detector on May 20, 2024, from a solar storm caused by the strong solar flares presently being pumped out by the Sun.

The mission regularly captures videos to try and catch dust devils, or dust-bearing whirlwinds. While none were spotted in this particular sequence of images, engineers did see streaks and specks – visual artifacts created when charged particles from the Sun hit the camera’s image detector. The particles do not damage the detector.

The images in this sequence appear grainy because navigation-camera images are processed to highlight changes in the landscape from frame to frame. When there isn’t much change — in this case, the rover was parked — more noise appears in the image.

Curiosity’s Radiation Assessment Detector (RAD) measured a sharp increase in radiation at this time – the biggest radiation surge the mission has seen since landing in 2012.

The view of this picture is to the south, looking towards the top of Mount Sharp, though that peak, more than 25 miles away, is not visible because the mountain’s lower flanks are in the way. A second movie showing similar charged particle streaks was taken looking south, with the rim of Gale Crater barely visible 20-30 miles away.

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The gullies on Mars are caused by a variety of factors, linked to both water and carbon dioxide

10:46 am

The global distribution of gullies on Mars
Click for original image.

In doing a detailed global analysis of all the known gullies on Mars, scientists now believe the gullies are formed by a variety of factors, linked to both water and carbon dioxide as well as the planet’s radically changing rotational tilt — varying from 11 to 60 degrees — over time.

Noblet’s paper articulates a “hierarchy of factors” that describes where gullies occur, with well-supported explanations as to why they form in one place and not another. None of the explanations in this paper are new. What’s new is how Noblet and coworkers reconcile apparent contradictions and inconsistencies among other researchers’ explanations of gully formation, explaining why an explanation that works for one spot on Mars doesn’t work in another.

The map above, from their paper, shows the global distribution of the gullies, which appear to favor the same mid-latitudes where the planet’s glaciers are mostly found. The data from many different studies suggests that when the planet’s rotational tilt was high, these mid-latitudes regions were warmer, and the near-surface ice there would sublimate away to get redeposited at the poles. When this happened the sublimation would cause the pole-facing gullies to form.

The paper also suggests that any gullies changing today are likely the result of the sublimation of carbon dioxide, not water.

There is a lot more at the article at the link, which is an excellent summation of this research.

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Research suggests a Mars mission will permanently damage a person’s kidneys

10:12 am

New research now suggests strongly that the exposure to cosmic rays during a three-year-long mission to Mars would cause permanent damage to a person’s kidneys.

The results indicated that both human and animal kidneys are ‘remodelled’ by the conditions in space, with specific kidney tubules responsible for fine tuning calcium and salt balance showing signs of shrinkage after less than a month in space. Researchers say the likely cause of this is microgravity rather than GCR [galactic cosmic rays], though further research is required to determine if the interaction of microgravity and GCR can accelerate or worsen these structural changes.

The primary reason that kidney stones develop during space missions had previously been assumed to be solely due to microgravity-induced bone loss that leads to a build-up of calcium in the urine. Rather, the UCL team’s findings indicated that the way the kidneys process salts is fundamentally altered by space flight and likely a primary contributor to kidney stone formation.

Perhaps the most alarming finding, at least for any astronaut considering a three-year round trip to Mars, is that the kidneys of mice exposed to radiation simulating GCR for 2.5 years experienced permanent damage and loss of function. [emphasis mine]

The study used samples “from over 40 Low Earth orbit space missions involving humans and mice, most of which were to the International Space Station, as well as 11 space simulations involving mice and rats.”

If these results are confirmed, it means that any interplanetary spaceship is going to require significant shielding. Having a safe haven they can go to during high energy solar events will not work, as cosmic rays arrive randomly at all times. This research thus tells us that we can’t simply add engines to the space station designs presently being built to send them to Mars. Instead, we need a heavy-lifte capability (such as Starship) to get the much heavier, well-shielded habitable modules into orbit.

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Ed Stone, who ran the Voyager missions for a half century, passes away at 88

9:54 am

Ed Stone, who was the project scientist for both Voyager missions to the outer solar system and beyond for a half century, passed away at 88 on June 9, 2024.

From 1972 until his retirement in 2022, Stone served as the project scientist from NASA’s longest-running mission, Voyager. The two Voyager probes took advantage of a celestial alignment that occurs just once every 176 years to visit Jupiter, Saturn, Uranus, and Neptune. During their journeys, the spacecraft revealed the first active volcanoes beyond Earth on Jupiter’s moon Io, and an atmosphere rich with organic molecules on Saturn’s moon Titan. Voyager 2 remains the only spacecraft to fly by Uranus and Neptune, revealing Uranus’ unusual tipped magnetic poles, and the icy geysers erupting from Neptune’s moon Triton.

Stone was also head of JPL from 1991 to 2001, during the time it built and flew the Mars Pathfinder mission, which sent the first rover to Red Planet. That mission revitalized the entire American Mars exploration program for the next three decades.

Stone was one of the giants of American space exploration during its formative years. He leaves behind a legacy that will be difficult to match, highlighted most of all by both Voyager spacecraft, which outlived him.

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Evidence of giant asteroid collision in debris disk surrounding the star Beta Pictoris

9:48 am

Data difference between Spitzer and Webb
Click for original figure.

Scientists comparing infrared data collected twenty years apart — first by the Spitzer Space Telescope and then by the Webb Space Telescope — think they have detected evidence of a gigantic asteroid collision in the debris disk that surrounds the very young star Beta Pictoris, located 63 light years away.

The graph to the right shows the change found between the observations. From the caption:

Scientists theorize that the massive amount of dust seen in the 2004–05 image from the Spitzer Space Telescope indicates a collision of asteroids that had largely cleared by the time the James Webb Space Telescope captured its images in 2023.

…When Spitzer collected the earlier data, scientists assumed something like small bodies grinding down would stir and replenish the dust steadily over time. But Webb’s new observations show the dust disappeared and was not replaced. The amount of dust kicked up is about 100,000 times the size of the asteroid that killed the dinosaurs, Chen said.

It is believed by scientists that the debris disk that surrounds Beta Pictoris is comparable to the early solar system when the planets first started to form. This collision could be similar to the kind of collision that is thought to have formed the Moon, when a large Mars-sized object smashed into the early Earth.

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Scientists: Water frost detected in calderas of four Martian volcanos

9:33 am

Frost found on four Martian volcanoes

Scientists using data from two European Mars orbiters think they have detected patches of transient water frost in the calderas of four Martian volcanos, all located in the dry equatorial regions of Mars where previously no near-surface ice has been seen.

According to the study, the frost is present for only a few hours after sunrise before it evaporates in sunlight. The frost is also incredibly thin — likely only one-hundredth of a millimeter thick or about the width of a human hair. Still, it’s quite vast. The researchers calculate the frost constitutes at least 150,000 tons of water that swaps between the surface and atmosphere each day during the cold seasons. That’s the equivalent of roughly 60 Olympic-size swimming pools.

You can read the research paper here. The volcanoes with frost were Olympus Mons, Arsia Mons, Ascraeus Mons, and Ceraunius Tholus, as shown by the blue dots on the overview map to the right. All are in the dry tropics of Mars.

The researchers believe the frost comes from the atmosphere, like dew forming in the morning on Earth. For it to take place at these high elevations on Mars however is astonishing. At these high elevations the atmosphere is extremely thin. Furthermore, the dry tropics have so far been found to contain no near-surface water or ice to fuel these processes.

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A close-up of rocks on Mars

10:30 am

Curiosity's robot arm about to take a close look at the ground
Click for original image.

Close-up of rocks on Mars
Click for original image.

Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken on June 6, 2024 by Curiosity’s Mars Hand Lens Imager (MAHLI), located at the end of the rover’s robot arm and designed to get close-up high resolution images of the ground that the arm is exploring.

The picture above, taken just after the one to the right and cropped, reduced, sharpened, and annotated to post here, shows the robot arm shortly after it has rotated upward after placing MAHLI right up against the ground. Note the tread marks. The science team apparently chose these target rocks because they were likely ground somewhat as the rover rolled over them, breaking the rocks to expose new faces.

According to the scientists, the camera was about two to three inches away from these rocks when it snapped the picture, with the scale about 16 to 25 microns per pixel. Since a micron is one millionth of a meter, this picture is showing us some very small details within a much larger rock.

I post this because I have rarely seen such colorful and crystal-like surface features from Curiosity.

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Webb detects carbon in early galaxy, far earlier than expected

8:43 am

The uncertainty of science: Astronomers using the Webb Space Telescope have detected evidence of carbon in a galaxy estimated to exist only 350 million years after the Big Bang, much sooner than any theory had predicted such an element could have developed.

“We were surprised to see carbon so early in the universe, since it was thought that the earliest stars produced much more oxygen than carbon,” said Maiolino. “We had thought that carbon was enriched much later, through entirely different processes, but the fact that it appears so early tells us that the very first stars may have operated very differently.”

According to some models, when the earliest stars exploded as supernovas, they may have released less energy than initially expected. In this case, carbon, which was in the stars’ outer shell and less gravitationally bound than oxygen, could have escaped more easily and spread throughout the galaxy, while a large amount of oxygen fell back and collapsed into a black hole.

The paper is available here.

The scientists are struggling to explain this result in the context of the Big Bang theory itself, and have come up with scenarios where it will work. However, the fact that Webb has found another data point suggesting the early universe was more complicated than any model predicted increases the difficulty in producing Big Bang models that will work.

All in all, there remains great uncertainty here. This particular observation required 65 hours of observation time. Pulling real data from these very distant points of light remains quite challenging.

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Telescope removed from Mauna Kea on Big Island as local Hawaiian council rejects new telescopes on Haleakala on Maui

8:09 am

Even as a local Hawaiian authority on the Big Island has completed the removal of the first of three telescopes on the top of Mauna Kea, a local council on the island of Maui have voted 9-0 to oppose an Air Force project to build new telescopes on top of Haleakala.

The proposed new facility is called AMOS STAR, which is an acronym for Air Force Maui Optical and Supercomputing Site Small Telescope Advanced Research. It would feature six telescopes enclosed in ground-mounted domes and one rooftop-mounted domed telescope.

The county’s resolution urged the military to heed community calls to cease their development efforts. It urged the National Park Service, Federal Aviation Administration and the Hawaii Department of Land and Natural Resources to deny the project permits.

At this time it appears that Hawaiians desended from the original indigenous population are opposed to all western technology, even as they rely on it. These new telescopes are proposed by the Air Force because it needs better capilities to track the tens of thousands of new satellites being launched by numerous companies and governments. This information will help prevent collisions in space.

As for their claims that these peaks are “considered wao akua, or ‘realm of the gods,’ and [places] of deep spirituality for Native Hawaiians to engage in some of these traditional practices,” as stated in the council’s resolution, I have some doubts. For almost three-quarters of a century such religious concerns and objections were never mentioned by anyone. If they existed indigenous Hawaiians appeared to have no problem “engaging in traditional practices” right next to telescopes. Only when some activists appeared in the past decade, looking to insert themselves in the process (thus obtaining positions of power and money) did the peaks become so important religiously.

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Lunar samples transferred to Chang’e-6 return vehicle

7:54 am

According to China’s state-run press, the ascent vehicle has docked with the Chang’e-6 orbiter and successfully transferred its lunar samples to the return spacecraft that will bring those samples back to Earth.

The ascender of China’s Chang’e-6 probe successfully rendezvoused and docked with the probe’s orbiter-returner combination in lunar orbit at 2:48 p.m. (Beijing Time) on Thursday, the China National Space Administration (CNSA) announced.

The container carrying the world’s first samples from the far side of the moon had been transferred from the ascender to the returner safely by 3:24 p.m., the CNSA said.

That return is scheduled for later this month. In the meantime the orbiter will adjust its position in preparation for sending the return capsule back.

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Hubble goes to one-gyro mode, limiting the telescope’s observational capabilities; NASA rejects private repair mission

9:59 am

Story Musgrave on the shuttle robot arm during the last spacewalk of the 1993 Hubble repair mission
Story Musgrave on the shuttle robot arm during
the last spacewalk of the 1993 Hubble repair mission

After the third safe mode event in six months, all caused by issues with the same gyroscope, engineers have decided to shift the Hubble Space Telescope to what they call one-gyro mode, whereby the telescope is pointed using only one gyroscope, and the remaining working gyro is kept in reserve.

The spacecraft had six new gyros installed during the fifth and final space shuttle servicing mission in 2009. To date, three of those gyros remain operational, including the gyro currently experiencing problems, which the team will continue to monitor. Hubble uses three gyros to maximize efficiency but can continue to make science observations with only one gyro. NASA first developed this plan more than 20 years ago, as the best operational mode to prolong Hubble’s life and allow it to successfully provide consistent science with fewer than three working gyros. Hubble previously operated in two-gyro mode, which is negligibly different from one-gyro mode, from 2005-2009. One-gyro operations were demonstrated in 2008 for a short time with no impact to science observation quality.

While continuing to make science observations in one-gyro mode, there are some expected minor limitations. The observatory will need more time to slew and lock onto a science target and won’t have as much flexibility as to where it can observe at any given time. It also will not be able to track moving objects closer than Mars, though these are rare targets for Hubble.

This NASA press release is carefully spun to hide the simple fact that in one-gyro mode, the telescope will simply not be able to take sharp pictures. » Read more

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Chang’e-6 ascender carrying lunar samples lifts off Moon

8:52 am

Chang'e-6's robot arm grabbing ground samples
Chang’e-6’s robot arm grabbing ground samples.
Image is a screen capture from mission control
main screen. Click for original.

Early today the ascender of China’s Chang’e-6 lunar probe lifted off the surface on the Moon’s far side, carrying the samples it had obtained both by drilling and the use of a robot arm.

The ascender took off at 7:38 a.m. (Beijing Time) from the moon’s far side. A 3,000-newton engine, after working for about six minutes, pushed the ascender to the preset lunar orbit, according to the CNSA.

The Chang’e-6 probe, comprising an orbiter, a lander, an ascender and a returner — like its predecessor Chang’e-5 — was launched on May 3. The lander-ascender combination, separated from the orbiter-returner combination on May 30, touched down at the designated landing area in the South Pole-Aitken (SPA) Basin on June 2.

The spacecraft finished its intelligent and rapid sampling work, and the samples were stowed in a container inside the ascender of the probe as planned, the CNSA said.

At some point, not yet specified, the ascender will dock with the orbiter-returner and transfer the samples to the returner, which after a period in orbit awaiting the right moment will then separate and head back to Earth.

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Sunspot update: In May the Sun went boom!

12:43 pm

As I have done at the start of every month since I begun this webpage back in 2010, I am posting NOAA’smonthly update of its graph tracking the number of sunspots on the Sun’s Earth-facing hemisphere, adding to it several additional details to provide some larger context.

While April had showed only a small uptick in sunspot activity, in May the sunspot activity on the Sun went boom, setting a new high for sunspots during this solar maximum as well as the highest sunspot count since September 2002. The sunspot count of 171.7 smashed the previous high of 160 this cycle, set in June 2023. This new high underlined was by the large solar flare on May 9th that sent the most powerful geomagnetic storm to hit the Earth’s magnetic field in many decades, producing spectacular auroras in many low latitudes.
» Read more

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China releases movie taken by Chang’e-6 during its lunar descent

8:45 am

Chang'e-6 landing zone
Chang’e-6’s landing zone is indicated by the
red box, on the edge of Apollo Creater
(indicated by the wavy circle).

China’s state-run press yesterday released a short movie created from images taken by its Chang’e-6 lander during its descent to the lunar surface on the far side of the Moon this past weekend.

I have embedded that footage below. The final five frames however are very puzzling, in that they do not appear to show a smooth descent to a specific spot, but appear to jump about wildly. Moreover, the footage does not appear to show the actual landing itself, but appears to stop while the spacecraft is still above the ground.

It is possible that this footage is simply showing the spacecraft’s software searching for a good landing spot, combined with a decision in China not to release footage of the actual touchdown. It could also be that something has gone wrong, and they are stalling about saying so. This last possibility I think very unlikely, but it must be considered, based on the information available.
» Read more

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Chang’e-6’s lander successfully soft lands on far side of the Moon

8:47 pm

Chang'e-6 landing zone
Chang’e-6’s landing zone is indicated by the
red box, on the edge of Apollo Creater
(indicated by the wavy circle).

China today announced that today at 6:23 pm (Eastern) the lander of its Chang’e-6’s lunar orbiter successfully soft landed on far side of the Moon.

Teams will now begin initial checks of the lander’s systems and soon begin collecting samples. The lander will collect up to 2,000 grams of samples, using a scoop to grab surface regolith and a drill for subsurface material. Samples are expected to be sent into lunar orbit within around 48 hours. Chinese space authorities have yet to publish a timeline for the mission and its steps, however.

Once docked to the orbiter, the samples will get transferred to the return spacecraft, which will return to Earth and land in China, in the same manner as was done with its Chang’e-5 sample return mission in 2021. Unlike those earlier samples, which came from the Moon’s near side (where the Apollo and Soviet samples had come from), these new samples will be first obtained from the far side.

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Gully erosion in a Martian dune field

2:26 pm

Overview map

Gully erosion in a Martian dune field
Click for original image.

Today’s cool image is another example of how little we really understand the geology of Mars. The picture to the right, rotated, cropped, reduced, and enhanced to post here, was taken on February 22, 2024 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).

The focus of the image is the eastern end of a large and very distinct dune field inside 31-mile-wide Matera Crater, as shown by the white rectangle in the overview map above. The field fills an area 10 by 11 miles inside the floor of the crater. On that eastern end is a very pronounced drainage gully dropping downhill about 2,000 feet to the east.

Gullies on Martian slopes, especially on the interior rims of craters, are not unusual. Though their true cause is not yet confirmed, the theories behind their existence all relate to some form of water/ice process, mostly relating to the seasonal freeze-thaw cycle.

This picture was taken in the spring, exactly when seasonal changes might be spotted. In fact, scientists have been taking regular MRO images of this gully since 2007, when it was featured image. From that 2007 caption:
» Read more

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Astronomers find another record-setting most distant galaxy

9:42 am

The uncertainty of science: Using the Webb Space Telescope, astonomers have identified another record-setting most distant galaxy, believed to exist only 300 million years after the Big Bang and once again far more massive and developed than expected that early in the universe.

The galaxy was actually one of two very early galaxies identified that lie close to each other on the sky but are not linked in any way.

The two record-breaking galaxies are called JADES-GS-z14-0 and JADES-GS-z14-1, the former being the more distant of the two. In addition to being the new distance record holder, JADES-GS-z14-0 is remarkable for how big and bright it is. “The size of the galaxy clearly proves that most of the light is being produced by large numbers of young stars,” said Eisenstein, a Harvard professor and chair of the astronomy department, “rather than material falling onto a supermassive black hole in the galaxy’s center, which would appear much smaller.”

The combination of the extreme brightness and the fact that young stars are fueling this high luminosity makes JADES-GS-z14-0 the most striking evidence yet found for the rapid formation of large, massive galaxies in the early Universe.

All the early galaxies that Webb has found so far have been far more massive and developed than cosmologists had predicted. The expectation had been that there wouldn’t have been enough time after the Big Bang for such galaxies to develop. Yet they have, suggesting something is not right with our theories about the beginning of the universe.

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The wind-carved north edge of Mars’ largest volcanic ash field

3:37 pm

The wind-carved north edge of Mars' largest volcanic ash field
Click for original image.

Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken on February 26, 2024 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows what the scientists label as the “relation between flutes and flows”.

The flood lava plain in the northern part of this picture represents the flows. At some point in the distant past some event, either a volcanic eruption, or a large impact, caused lava to spew out across this terrain, leaving behind a smooth plain that has only partly been marked by later crater impacts.

The many parallel ridges pointing to the northeast in the southern part of the picture represent the flutes.

One other very important flow is not directly visible. The prevailing winds that blow to the southwest are what carved these flutes, slowly pushing the material southward while carving out the many gaps between the ridges.
» Read more

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Scientists propose three scenarios for the creation of Dinkinesh’s contact-binary moon Selam

10:23 am

Three scenarios for creating Dinkinesh and Salem
Click for original graphic.

Dinkinesh's contact binary moon
Click for original image.

Scientists have now used the data obtained during Lucy’s close fly-by of the asteroid Dinkinesh in November 2023 to propose three scenarios to explain the existence of its contact-binary moon Selam, as well as the trough and equatorial ridge on Dinkinesh.

The image to the right shows Selam to the right of Dinkenesh. The graphic above shows the three scenarios proposed for Selam’s creation. This is figure 4 from the paper published today. From the caption:

Asteroids with diameters less than approximately 10 km are subject to spin-up by the YORP effect [changes to rotation and motion due to solar radiation impacting the asteroid’s surface]. Rapid spin of the primary and the associated centrifugal force eventually trigger a structural failure that leads to sudden mass shedding. This event might also have created the trough seen on Dinkinesh through the mass movement of a portion of the body. The shed material forms a ring, with some material coalescing into a satellite(s) and closer material eventually falling back to the surface at the equator to form the ridge. The formation of the contact binary may be the result of a merger of two satellites formed either in a single mass-shedding event (a) or in two separate events (b). An alternative scenario (c) is that Selam formed as a single object that subsequently underwent fission owing to spin–orbit coupling.

Of course, none of this is confirmed, though these hypotheses fit the available facts.

Lucy is presently heading to a fly-by of Earth in December 2024. It will then zip past another main belt asteroid in April 2025 before arriving in August 2027 among the Trojan asteroids in Jupter’s orbit. Once there it will visit at least eight different asteroids.

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The “Vulcan” exoplanet discovered in 2018 now refuted

9:52 am

In 2018 astronomers had thought they had detected an exoplanet orbiting the star 40 Eridani A — which is where in Star Trek the home world Mr. Spock was supposed to be located.

That discovery has now been refuted by much more precise observations.

[T]he planet signal is really the flickering of something on the star’s surface that coincides with a 42-day rotation – perhaps the roiling of hotter and cooler layers beneath the star’s surface, called convection, combined with stellar surface features such as spots and “plages,” which are bright, active regions.

In other words, this exoplanet does not exist. For once at least life did not imitate art.

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Chang’e-6 to attempt landing on Moon’s far side on June 1st

9:42 am

Chang'e-6 landing zone

After spending almost a month in lunar orbit, the lander on China’s Chang’e-6 sample return mission will attempt a soft touchdown on Moon’s far side on June 1, 2024 at 8:00 pm (Eastern).

If successful, the lander will go through initial checks and setup. It will then begin drilling and scooping up materials from the surface. These samples, expected to weigh up to 2,000 grams, will be loaded into an ascent vehicle. The ascender will then launch the precious cargo back into lunar orbit for rendezvous and docking with the orbiter. Surface operations will last about 48 hours.

The map to the right indicates the landing zone by the red box, on the southern edge of Apollo Crater, indicated by the wavy white circle. The black circle marks the perimeter of South Aitken Basin, the largest impact basin on the Moon.

Once the ascender docks with the orbiter, the sample will be transferred into the sample return capsule, which will bring that sample back to Earth in late June.

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A Martian lava flow so strong it eats mountains

1:34 pm

A Martian lava flow so strong it eats mountains
Click for original image.

Cool image time! The picture to the right, rotated, cropped, reduced, sharpened, and annotated to post here, was taken on March 19, 2024 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows a crater that appears to sit on top of a plateau that was created by a flow of material coming from the northeast that — as the flow divided to get around that crater — it wore away the ground to leave the crater sitting high and dry.

What was the material in that flow? The location is at 9 degrees north latitude, in Mars’ dry tropics, so it is highly unlikely that the flows here are glaciers, even though they have some glacier-like features.

Instead, this is frozen lava, but Martian in nature in that its ability to push the ground out of its way suggests it was moving very fast, far faster than lava on Earth.
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Dry ice and carbon monoxide detected on asteroids beyond Neptune

9:31 am

Based on new infrared observations by the Webb Space Telescope, scientists have detected for the first time carbon dioxide and carbon monoxide on asteroids beyond Neptune. From the abstract of their paper:

Out of 59 [trans-Neptunian objects] and centaur [asteriods] observed by the James Webb Space Telescope and the NIRSpec Integral Field Unit as part of the DiSCo-TNOs project, we report the widespread detection of CO2 ice in 95% of the sample and CO ice in 47% of the sample.

It appears dry ice is ubiquitous in the outer solar system. Since it is believed these asteroids are very primitive, this data suggests there was a lot of it in the early solar system when the planets were forming.

The discovery of so much carbon monoxide is however more puzzling, as it is expected to sublimate away even in the very cold environment so far from the Sun and is therefore likely not from the early solar system. The scientists posit that it might have been produced when radiation transformed the other carbon-bearing ices.

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Scientists confirm 2023 data that suggested active volcanism on Venus

9:20 am

Active lava flows on Venus
Click for original video

Scientists have now confirmed a 2023 paper that had found evidence in archival data from the Magellan orbiter that there was active volcanism on Venus. From the abstract of the new paper:

To investigate more widespread alterations that have occurred over time in the planet’s surface morphology, we compared radar images of the same regions observed from 1990 to 1992 with the Magellan spacecraft. We found variations in the radar backscatter from different volcanic-related flow features on the western flank of Sif Mons and in western Niobe Planitia. We suggest that these changes are most reasonably explained as evidence of new lava flows related to volcanic activities that took place during the Magellan spacecraft’s mapping mission with its synthetic-aperture radar.

The image to the right is a screen capture, annotated to post here, from a video computer animation created by the science team based on that Magellan data. The red areas are where the scientists detected lava flow changes on the flanks of the volcano Sif Mons. From the press release:

Using flows on Earth as a comparison, the researchers estimate new rock that was emplaced in both locations to be between 10 and 66 feet (3 and 20 meters) deep, on average. They also estimate that the Sif Mons eruption produced about 12 square miles (30 square kilometers) of rock — enough to fill at least 36,000 Olympic-size swimming pools. The Niobe Planitia eruption produced about 17 square miles (45 square kilometers) of rock, which would fill 54,000 Olympic swimming pools. As a comparison, the 2022 eruption of Mauna Loa in Hawaii, Earth’s largest active volcano, produced a lava flow with enough material to fill 100,000 Olympic pools.

There is uncertainty of course with this result, due to the difficulty of analyzing radar data properly. Nonetheless, this result reinforces last year’s results, which saw evidence of changes between the two Magellan data sets in a different region near the volcanoes Ozza Mons and Maat Mons. It also reinforces previous work going back decades that has repeatedly suggested Venus was volcanically active.

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Visiting a galactic bar

9:27 am

Visiting a galactic bar
Click for original image.

Cool image time! The picture to the right, reduced and sharpened to post here, was taken by the Hubble Space Telescope as part of a research project studying the flow of gases inside barred galaxies. It shows a spiral galaxy, NGC 4731, edge on, located about 43 million light years away. From the caption:

Barred spiral galaxies outnumber both regular spirals and elliptical galaxies put together, numbering around 60% of all galaxies. The visible bar structure is a result of orbits of stars and gas in the galaxy lining up, forming a dense region that individual stars move in and out of over time. This is the same process that maintains a galaxy’s spiral arms, but it is somewhat more mysterious for bars: spiral galaxies seem to form bars in their centres as they mature, accounting for the large number of bars we see today, but can also lose them later on as the accumulated mass along the bar grows unstable. The orbital patterns and the gravitational interactions within a galaxy that sustain the bar also transport matter and energy into it, fuelling star formation.

Astronomers don’t really understand why these barred structures develop, since you would expect the overall gravity of the galaxy would promote a spiral or spherical shape. There must are factors not yet understood or completely identified (such as the magnetic fields of such galaxies).

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Rocket Lab launches NASA climate satellite

10:41 pm

Rocket Lab today successfully launched the first of two NASA PREFIRE climate satellites, its Electron rocket lifting off from its launchpad in New Zealand.

The leaders in the 2024 launch race:

55 SpaceX
23 China
7 Russia
6 Rocket Lab

American private enterprise now leads the world combined in successful launches, 63 to 36, while SpaceX by itself leads the entire world, including other American companies, 55 to 44.

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