Tag: science

New Hawaiian law takes control of Mauna Kea away from astronomers

9:01 am

A newly passed Hawaiian law has taken the management of the top of Mauna Kea away from the University of Hawaii and given it to a new community authority which will include many of the activists who have blocked the construction of the Thirty Meter Telescope (TMT).

The new Maunakea authority will include Native Hawaiians in decisions about how the mountain is managed, with an emphasis on mutual stewardship and protecting Maunakea for generations to come. The authority will have 11 voting members, one of whom must be an active practitioner of Native Hawaiian cultural traditions, and one of whom must be a descendant of a cultural practitioner who is associated with Maunakea. There are also spots for representatives drawn from astronomy, education, land management, politics and other fields.

“I’m very hopeful for the new entity,” says Noe Noe Wong-Wilson, a Native Hawaiian elder who has helped to lead road blocks on the mountain. “It is beyond my imagination of where we would be at this time, because we have fought so long to be heard.”

The University of Hawaii has managed most of the lands around the Maunakea summit since 1968, when the state granted it a 65-year lease to operate a scientific reserve focused on astronomy. Maunakea has ideal skies for astronomical observation, given its 4,200-metre height and its stable and dark night skies. The university now has to transfer all of its management duties, including a complex set of subleases, permits and other agreements, to the new authority by 1 July 2028. [emphasis mine]

From the beginning of the protesters against TMT I made several predictions, all of which are now coming true.

  • This is a power play by some activist protesters for money and power. The new law gives them that.
  • The Democratic Party that controls Hawaii utterly supports the protesters, and was working behind the scenes to aid them. The new law proves that.
  • TMT will never be built. This new law makes that prediction almost certain.
  • The real goal of the protesters will be the eventual shut down of all astronomy on Mauna Kea. This new law is the first step in that process.

Forget about TMT. It is dead, as are any new telescopes or upgrades on Mauna Kea. Sometime around 2028, when this new authority takes over, we shall begin to see demands for the removal of telescopes.

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Icy scarps in the high southern latitudes of Mars

1:25 pm

Icy scallops in the high southern latitudes of Mars
Click for full image.

Cool image time! The photo to the right, rotated, cropped, and reduced to post here, was taken on May 30, 2022 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows what the scientists label “Patching Mantling Unit,” located at about 57 degrees south latitude in a region where scientists have found good evidence of near surface ice. The top layer, or mantle, is likely patchy because it has a high content of water ice and is sublimating away. That almost all the cliffs are south-facing, which in the southern hemisphere gets the least direct sunlight, supports this supposition. For example, in the crater at the bottom of the image the ice would have disappeared first from the north-facing interior rim slopes, with the sublimation slowly working its way northward. Thus we have that butte extending out from the north rim.

The global map below not only indicates the location of these scallops with the green dot, it illustrates the overall icy nature of most of the Mars.
» Read more

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Roscosmos forbids its astronauts from using Europe’s robot arm

9:19 am

In response to the final decision this week by the European Space Agency to officially end its cooperation with Russia on its ExoMars mission, Roscosmos today forbid its astronauts from using Europe’s new robot arm that was recently installed on the Russian Nauka module of ISS.

Russia’s crew onboard the International Space Station (ISS) will stop using the European ERA manipulator arm in response to the European Space Agency’s (ESA) refusal from cooperation on the ExoMars project, CEO of Russia’s state space corporation Roscosmos Dmitry Rogozin said on Tuesday.

“In my turn, I instruct our ISS crew to stop using the European Robotic Arm (ERA). Let [ESA Director General Josef] Aschbacher along with his boss [EU foreign policy chief Josep] Borrell fly to space and do at least something useful in their entire lives,” he wrote on his Telegram channel.

The arm was designed to work on the Russian part of ISS, so it appears this decision by Rogozin is an example of someone cutting off his nose to spite his face. It essentially reduces Russia’s capabilities on the station.

As for ExoMars, it is unclear what will happen to the lander that Russia built to put Europe’s Franklin rover on Mars. Roscosmos has said it might proceed with its own mission to Mars, using that lander, but it has not made the full commitment to do so.

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The highest point on Mars

12:41 pm

The highest point on Mars
Click for full image.

Today’s cool image is cool not because of anything visible within it, but because of its location. The picture to the right, cropped to post here, was taken on May 27, 2022 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). While the terrain shown is a relatively featureless plain of craters and gullies not unlike the surface of the Moon, what we are really looking at is the peak of Mars’ tallest mountain, Olympus Mons.

That’s right, this spot on Mars sits about 70,000 feet above Mars’ mean “sea level”, the elevation scientists have chosen as the average elevation on Mars from its center. At 70,000 feet, this peak is more than twice as high as Mount Everest on Earth.

Yet you wouldn’t really know you are at this height if you stood there. The scale of this mountain is so large that this peak, which actually forms the southern rim of the volcano’s 50 to 60 mile wide caldera, is actually relatively flat. If you stood here, you would not see the vast distant terrain far below. Instead, you’d see an ordinary horizon line in the near distance only slightly lower than where you stand.
» Read more

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Today’s blacklisted American: Scientists questioning Big Bang theory protest censorship of their work

11:38 am

Webb's first deep field image
Nothing in Webb’s first deep field image shall be questioned, by anyone!

While the blacklisting described in today’s column has little to do with left vs right politics, it demonstrates clearly that the desire to silence dissent is now culturally pervasive across many fields. In science it has become especially toxic, as this story clearly shows:

Twenty-four astronomers and physicists from ten countries have signed a petition protesting the censorship of papers that are critical of the Big Bang Hypothesis by the open pre-print website arXiv. Run by Cornell University, arXiv is supposed to provide an open public forum for researchers to exchange pre-publication papers, without peer-review. But during June, 2022, arXiv rejected for publication on the website three papers by Dr. Riccardo Scarpa, Instituto de Astrofisica de Canarias, and Eric J. Lerner, LPPFusion, Inc. which are critical of the validity of the Big Bang hypothesis.

…[quoting the petition] “Without judging the scientific validity of the papers, it is clear to us that these papers are both original and substantive and are of interest to all those concerned with the current crisis in cosmology. It plainly appears that arXiv has refused publication to these papers only because of their conclusions, which both provide specific predictions relevant to forthcoming observations and challenge LCDM cosmology [the standard dark matter/dark energy Big Bang hypothesis]. Such censorship is anathema to scientific discourse and to the possibility of scientific advance.

“We strongly urge that arXiv maintain its long-standing practice of being an “open-access archive” of non-peer reviewed “scholarly articles” and not violate that worthy practice by imposing any censorship. Instead, we encourage arXiv to abide by its own principles, and publish these three papers and others like them that clearly provide ‘sufficient original or substantive scholarly research’ results and are of obvious great interest to the arXiv audience.”

Lerner and Scarpa had attempted to get their papers published in a peer review journal and had been stymied, apparently because the topic of their paper was inappropriate for that journal. They then decided to publish on arXiv, which has for almost three decades been open to the publication of all scientific papers written by credentialed scientists, as noted at the website:
» Read more

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More Webb images released

9:08 am

Southern Ring Nebula, as taken by Webb
Click for full image.

As planned, NASA this morning released four new science images from the James Webb Space Telescope, in addition to the deep field image released yesterday.

All are spectacular, with each producing new information not previously observed. To see the Stephen’s Quintet image go here. For the exoplanet data, showing the presence of water in its atmosphere, go here. For the Carina nebula image, go here.

The image to the right, reduced to post here, shows the Southern Ring Nebula as taken by two Webb cameras in different infrared wavelengths. From the press release:

Two stars, which are locked in a tight orbit, shape the local landscape. Webb’s infrared images feature new details in this complex system. The stars – and their layers of light – are prominent in the image from Webb’s Near-Infrared Camera (NIRCam) [at the top], while the image from Webb’s Mid-Infrared Instrument (MIRI) on the [bottom] shows for the first time that the second star is surrounded by dust. The brighter star is in an earlier stage of its stellar evolution and will probably eject its own planetary nebula in the future.

In the meantime, the brighter star influences the nebula’s appearance. As the pair continues to orbit one another, they “stir the pot” of gas and dust, causing asymmetrical patterns.

Because this is an infrared image, the colors are not natural, but were assigned based on the slightly different infrared wavelengths produced by the object’s different features. From the image’s webpage:

Several filters were used to sample narrow and broad wavelength ranges. The color results from assigning different hues (colors) to each monochromatic (grayscale) image associated with an individual filter.

Eventually astronomers will use Webb to look at many astronomical objects that Hubble has been observing for the past thirty years, adding a high resolution infrared view that will add to Hubble’s views.

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First science image released from Webb

3:40 pm

Webb's first deep field image
Click for original image.

The first science image from the James Webb Space Telescope has now been unveiled.

That image is to the right, reduced to post here. From the press release:

Known as Webb’s First Deep Field, this image of galaxy cluster SMACS 0723 is overflowing with detail. Thousands of galaxies – including the faintest objects ever observed in the infrared – have appeared in Webb’s view for the first time. This slice of the vast universe covers a patch of sky approximately the size of a grain of sand held at arm’s length by someone on the ground.

This deep field, taken by Webb’s Near-Infrared Camera (NIRCam), is a composite made from images at different wavelengths, totaling 12.5 hours – achieving depths at infrared wavelengths beyond the Hubble Space Telescope’s deepest fields, which took weeks.

The image shows the galaxy cluster SMACS 0723 as it appeared 4.6 billion years ago. The combined mass of this galaxy cluster acts as a gravitational lens, magnifying much more distant galaxies behind it. Webb’s NIRCam has brought those distant galaxies into sharp focus – they have tiny, faint structures that have never been seen before, including star clusters and diffuse features.

The smeared concentric arrangement of many reddish objects surrounding the picture’s center strongly suggests we are seeing distortion by the gravity of this galaxy cluster.

While nothing in this image appears at first glance to be different than many earlier Hubble images, it looks at objects in the infrared that are much farther away than anything ever seen before, farther than Hubble in the optical could see. To understand the new discoveries hidden in such an image will likely take several years of further research. For example, before astronomers can understand what this image shows they need to determine the red shift of each galaxy, thus roughly determining its distance and the overall 3D structure of the objects visible. Moreover, the consequences of the gravitational lensing must be unpacked.

The White House briefing itself was somewhat embarrassing to watch, as Vice President Kamala Harris, President Joe Biden, and NASA administrator Bill Nelson all struggled to explain what this image shows, and failed miserably. Moreover, the briefing had technical problems, started very late, and it appeared that Bill Nelson especially had no idea what he was looking at. The briefing also ended very abruptly when it shifted to reporters’ questions.

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Collapse pits on Mars

2:08 pm

Elongated collapse pit on Mars
Click for full image.

Cool image time! The photo to the right, cropped to post here, was taken on May 21, 2022 and was today’s picture of the day from the high resolution camera on Mars Reconnaissance Orbiter (MRO). Dubbed “An Elongated Collapse Pit” by the science team, their caption explains:

This observation can help to tell whether or not there is a subterranean connection to this pit. As an added bonus, the much smaller depression to its south also appears to be another collapse pit.

This image had already been in my queue for a future cool image post, but since the scientists have posted it, it is time that I did as well.

In the inset I have brightened the image drastically to try to illuminate the darkest spots in both pits. The elongated pit appears to slope downward towards a hole in the southeast corner, while the interior of the second pit to the south remains completely dark. Both appear to suggest a void below that both reach.

The wider context image and overview map below shows that there is further evidence of more voids in this region of Mars, dubbed Ceraunius Fossae, because of its many north-south parallel fissures.
» Read more

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More lacy Martian rocks

9:59 am

lacy Martian rock
Click for full image.

Cool image time! Because the Curiosity team is presently conducting a drilling campaign at its present position in the lower mountains of Gale Crater, the rover has not moved in the past few weeks. At these times, the science team also has the rover’s other cameras do extensive surveys of the surrounding terrain, including high resolution mosaics by its high resolution camera.

To the right is one photo from the most recent mosaic, cropped to post here. It was taken on July 10, 2022, and shows one many layered rock on the ground near the rover. Though no scale is provided, I suspect the extended flake from this rock is somewhere between six to twelve inches long.

Another illustration of the alien nature of Mars. This flake could not exist on Earth, where the heavier gravity and atmosphere would have acted to break it.

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Biden to unveil first Webb science image today

9:27 am

This should be entertaining: NASA today announced that the unveiling of the first science image from the James Webb Space Telescope has been moved up to later today, so that President Joe Biden can do the unveiling from the White House. From the NASA tweet:

We can’t contain the excitement for @NASAWebb’s first full-color images!

On Monday, July 11 at 5pm ET (21:00 UTC), President Biden will unveil one of the space telescope’s first images of deep space as a preview of what’s ahead.

It appears that the picture Biden will use in this photo op will be the only deep field cosmological picture scheduled for release:

SMACS 0723: Massive foreground galaxy clusters magnify and distort the light of objects behind them, permitting a deep field view into both the extremely distant and intrinsically faint galaxy populations.

The remaining four images will still be released on July 12, 2022, as originally planned.

The live stream of this event will be broadcast on NASA TV.

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A galaxy with swirling arms

9:17 am

A galaxy with swirling arms
Click for full image.

Cool image time! The picture to the right, cropped and reduced to post here, was released yesterday by the science team that operates the Hubble Space Telescope. It captures a galaxy about 520 million light years away that appears to have been reshaped due to a galaxy merger.

That merger somehow distorted the disk of the inner galaxy, the brightest area, while also producing two sweeping spiral streams in the surrounding periphery.

Despite its unusual shape, astronomers did not choose to study this galaxy. From the caption:

This observation is a gem from the Galaxy Zoo project, a citizen science project involving hundreds of thousands of volunteers from around the world who classified galaxies to help scientists solve a problem of astronomical proportions: how to sort through the vast amounts of data generated by telescopes. A public vote selected the most astronomically intriguing objects for follow-up observations with Hubble. CGCG 396-2 is one such object, imaged here by Hubble’s Advanced Camera for Surveys.

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The colorful layers of the Martian north pole icecap

1:44 pm

Colorful layers in the Martian north pole ice cap
Click for full image.

Wider view
Click for full image.

Today’s cool image above, rotated, reduced, and annotated to post here, comes from today’s picture of the day for the high resolution camera on Mars Reconnaissance Orbiter (MRO), which in turn is a retrospective of a captioned image first taken in 2010. The photo to the right, rotated, cropped, and reduced to post here, shows a larger area to provide some context. For this image north is towards the top. The rectangle indicates the area covered by the picture above.

The ice cap at the north pole is about 600 miles across and a little less than 7,000 feet deep, made up of many layers that are a mixture of water ice and cemented dust and sand. From the picture’s caption:

In many locations erosion has created scarps and troughs that expose this layering. The tan colored layers are the dusty water ice of the polar layered deposits; however a section of bluish layers is visible below them. These bluish layers contain sand-sized rock fragments that likely formed a large polar dunefield before the overlying dusty ice was deposited.

The lack of a polar ice cap in this past epoch attests to the variability of the Martian climate, which undergoes larger changes over time than that of the Earth.

The overview map below provides some further context.
» Read more

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NASA announces the targets picked for Webb’s first science images

10:20 am

NASA today announced the astronomical targets scientists have chosen for the first infrared science images taken by the James Webb Space Telescope which will be unveiled on July 12, 2022.

  • Carina Nebula. The Carina Nebula is one of the largest and brightest nebulae in the sky, located approximately 7,600 light-years away in the southern constellation Carina. Nebulae are stellar nurseries where stars form. The Carina Nebula is home to many massive stars, several times larger than the Sun.
  • WASP-96 b (spectrum). WASP-96 b is a giant planet outside our solar system, composed mainly of gas. The planet, located nearly 1,150 light-years from Earth, orbits its star every 3.4 days. It has about half the mass of Jupiter, and its discovery was announced in 2014.
  • Southern Ring Nebula. The Southern Ring, or “Eight-Burst” nebula, is a planetary nebula – an expanding cloud of gas, surrounding a dying star. It is nearly half a light-year in diameter and is located approximately 2,000 light years away from Earth.
  • Stephan’s Quintet: About 290 million light-years away, Stephan’s Quintet is located in the constellation Pegasus. It is notable for being the first compact galaxy group ever discovered in 1877. Four of the five galaxies within the quintet are locked in a cosmic dance of repeated close encounters.
  • SMACS 0723: Massive foreground galaxy clusters magnify and distort the light of objects behind them, permitting a deep field view into both the extremely distant and intrinsically faint galaxy populations.

That only the last image is focused on distant deep space cosmology, the scientific research that Webb’s infrared instruments are optimized for suggests that NASA wishes to highlight the telescope’s other observational possibilities.

The images will be released one by one during a press conference beginning at 10:30 am (Eastern) on July 12th. It is once again important to note that though the images are likely to be spectacular, they will be false color infrared images measuring the heat produced by the objects, not optical images that we could see with our eyes.

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OSIRIS-REx’s sample grab at Bennu in 2020 proved the rubble-pile asteroid has far less cohesion than predicted

10:10 am

The post touchdown crater on Bennu

The OSIRIS-REx science team, using data gathered during the spacecraft’s sample grab at Bennu in 2020, has determined that the rubble-pile asteroid has far less cohesion than predicted, with its rubble behaving less like a solid object and more like the playground ball-pits found in amusement parks.

After analyzing data gathered when NASA’s OSIRIS-REx spacecraft collected a sample from asteroid Bennu in October 2020, scientists have learned something astonishing: The spacecraft would have sunk into Bennu had it not fired its thrusters to back away immediately after it grabbed dust and rock from the asteroid’s surface.

It turns out that the particles making up Bennu’s exterior are so loosely packed and lightly bound to each other that if a person were to step onto Bennu they would feel very little resistance, as if stepping into a pit of plastic balls that are popular play areas for kids.

The image above shows what the touch down crater looked like after the sample grab, taken from the video that was part of the press release. The false colors indicate the depth changes produced by the touch down. The final crater was 26 feet across and more than two feet in depth, far larger than expected. Moreover, the energy from the spacecraft’s thrusters as it lifted off had increased the size of that crater further, by about 40%.

These results about the asteroid’s lack of cohesion match the earlier results studying a different impact crater on Bennu.

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From the rim to the floor of Valles Marineris

5:01 pm

Overview map

From the rim to the floor of Valles Marineris
Click for full image.

For today’s cool Martian image, we begin from afar and zoom in. The overview map above shows the solar system’s largest canyon, Valles Marineris, 1,500 miles long, and 400 miles wide at its widest. The white dot on the north rim of the section of the canyon dubbed Melas marks the location of the photo to the right, rotated, cropped and reduced to post here and taken on January 28, 2011 by the wide angle context camera on Mars Reconnaissance Orbiter (MRO).

I have added elevation numbers to this picture to give it some understandable scale. From the rim to the interior canyon floor — a distance of about ten miles — the canyon wall drops about 19,000 feet. Compare this with Bright Angel Trail in the Grand Canyon, which from the rim to the Colorado River drops about 4,400 feet in about the same distance. The wall of Valles Marineris is about four times steeper.

Even that doesn’t give you the full scale. Having hiked down to that interior canyon floor, you are still about 10,000 feet above Valles Marineris’s main canyon floor, with fifteen more miles of hiking to go to reach it.

The white rectangle marks the area covered by the MRO high resolution image below.
» Read more

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Today’s blacklisted American: Thomas Jefferson and other important American historical figures banned by Cleveland school authorities

11:52 am

Thomas Jefferson banned in Cleveland
Thomas Jefferson, banned by Cleveland school officials

The modern dark age: Officials of Cleveland Metropolitan Schools have decided that its schools cannot be named after Thomas Jefferson and Patrick Henry because these great Americans — who trail-blazed the fight for individual freedom — had also owned slaves.

Guidelines implemented by the district last year with the urging of the Cleveland City Council require that schools not be named after people who have a documented history of enslaving other humans.

The district also prohibits naming schools for those who have actively participated in the institution of slavery, systemic racism, the oppression of people of color, women, or other minority groups, or who have been a member of a supremacist organization.

The two schools are now named after a black Democratic Party politician and a former school official. In our new dark age, these relatively minor individuals are now considered more important than two giants who made it possible to found the first country on Earth dedicated to freedom and individual liberty where the people were sovereign and the government was only their servant.
» Read more

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CAPSTONE completes mid-course correction

10:39 am

Engineers at Advanced Space today successfully completed CAPSTONE’s first mid-course correction, following a quick investigation that determined why communications with the probe was lost for almost a full day.

The communications blackout was apparently due to software issues and human error.

During [in-flight] commissioning of NASA’s CAPSTONE (short for Cislunar Autonomous Positioning System Technology Operations and Navigation Experiment) spacecraft, the Deep Space Network team noted inconsistent ranging data. While investigating this, the spacecraft operations team attempted to access diagnostic data on the spacecraft’s radio and sent an improperly formatted command that made the radio inoperable. The spacecraft fault detection system should have immediately rebooted the radio but did not because of a fault in the spacecraft flight software.

CAPSTONE’s autonomous flight software system eventually cleared the fault and brought the spacecraft back into communication with the ground, allowing the team to implement recovery procedures and begin commanding the spacecraft again.

All looks good for a November 13, 2022 arrival in lunar orbit.

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Scientists: Impacts on rubble-pile asteroid are different than on planets

10:27 am

Landslide on Bennu from impact
Click for full image.

Using data collected by OSIRIS-REx at the asteriod Bennu, scientists have determined that the ejecta from impacts on a rubble-pile asteroid behaves in a very different manner than on planets with higher gravity.

Instead of flying away at about the same speed as the impactor and escaping into space, as expected in the weak gravity, the material is lifted up at a very slow speed, falls back down, and then rolls downhill like a landslide. The graphic to the right from the press release, reduced and enhanced to post here, illustrates what the scientists think happened when one of Bennu’s larger craters was created.

[M]ost of that material, called ejecta, returned to the surface and slid down the face of the asteroid, starting a wide avalanche that slowly rolled toward Bennu’s equator. Perry said the only way this could happen on a small object like Bennu, which is less than 500 meters (1,640 feet) in diameter and has low gravity, is if the dust had low or next to no cohesion.

“Because Bennu is so small, its escape velocity is less than a few tenths of a mile per hour, so any particle ejected faster than that would leave the surface,” he said. “These slow speeds are possible only if Bennu’s surface is weaker than we thought, even weaker than very loose, dry sand. This extremely low surface strength also means material on a slope is easily disturbed, and that’s what led to the landslide.”

In other words, the low cohesion prevents the impact’s energy from being transferred efficiently to the asteroid’s particles. They move, but only slowly, and thus end up sliding away more or less along the asteroid’s surface.

This discovery helps explain how these rubble-pile asteroids accumulate material, despite their low gravity.

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Having regained communications with CAPSTONE, engineers prepare for first mid-course burn

8:55 pm

Engineers are now preparing CAPSTONE for its first first mid-course engine burn, slightly late due to a loss of communications during the past two days.

The spacecraft is in good health and functioning properly.

The CAPSTONE team is still actively working to fully establish the root cause of the issue. Ground-based testing suggests the issue was triggered during commissioning activities of the communications system. The team will continue to evaluate the data leading up to the communications issue and monitor CAPSTONE’s status.

If all goes well, that engine burn will occur as early as 11:30 am (Eastern) on July 7th.

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How did sand dunes get to the top of a Martian mesa?

1:51 pm

Sand dunes at the top of a Martian mountain
Click for full image.

Cool image time! The photo to the right, cropped and reduced to post here, was taken on January 1, 2022 by the high resolution camera on Mars Reconnaissance Orbiter (MRO) and shows one of the peaks of a 5,000+ foot high mesa inside Juventai Chasma, one of Mars’ deep mostly-enclosed chasms north of Valles Marineris.

I grabbed this picture because its label, “Bedform Change Detection in Juventae Chasma”, suggested something had changed from past photos, probably related to the sand dunes that hug the upper slopes of this peak. Unfortunately, in comparing this image with the earliest high-res image taken by MRO back in February 2018, I could not spot any change, probably because the resolution of the pictures released is not as high as MRO’s raw images.

However, the caption written for that 2018 image tells us where that change has likely occurred:

This image reveals a unique situation where this small dune field occurs along the summit of the large 1-mile-tall [mesa] near the center of Juventae Chasma. The layered [mesa] slopes are far too steep for dunes to climb, and bedform sand is unlikely to come from purely airborne material. Instead, the mound’s summit displays several dark-toned, mantled deposits that are adjacent to the dunes and appear to be eroding into fans of sandy material.

In other words, somewhere in the full resolution image scientists have spotted a change in the bedform sands that make-up these high mountain dunes that hug the peak. Since the data so far has suggested that the source for the sand of these high elevation dunes likely comes from the mesa itself — not from any distant source — any change found will help confirm or disprove that hypothesis.

The white box indicates the area covered by the close-up higher resolution picture below. Also below is an overview map, showing both the location of this mountain in Juventai Chasma as well as Juventai’s location relative to Valles Marineris.
» Read more

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