Embedded below the fold in two parts.
To listen to all of John Batchelor’s podcasts, go here.
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Since the first two launches earlier today, we have seen two more launches successfully completed.
First Russia placed a classified military payload into orbit, its Soyuz-2 rocket lifting off from its Plesetsk spaceport in northeast Russia. The fairings and first three stages all crashed inside Russia. No word if they landed near habitable areas, though the regions are generally sparsely inhabited.
Then SpaceX completed its second launch today, placing another 20 Starlink satellites into orbit, its Falcon 9 rocket lifting off from Vandenberg in California. Of the satellites thirteen were configured for direct-to-cell service. For the second time in the last week the company broadcast did not begin until after liftoff. In both cases the reason might be to avoid revealing any visuals of the rocket’s fairing, suggesting that SpaceX was using something different that it wanted to keep secret.
The first stage completed its twelfth flight, landing on a drone ship in the Pacific.
Not surprisingly, two of the launches previously scheduled for today have been postponed. The PSLV launch of a European solar telescope was delayed one day due to an issue detected with the payload’s propulsion system, while the first launch in two years of Arianespace’s Vega-C rocket was delayed because of an unspecified “mechanical issue.” At present Arianespace is targeting a launch for tomorrow.
The leaders in the 2024 launch race:
126 SpaceX
58 China
16 Russia
13 Rocket Lab
American private enterprise still leads the rest of the world combined in successful launches 145 to 87, while SpaceX by itself leads the entire world, including American companies, 126 to 106.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The print edition can be purchased at Amazon, any other book seller, or direct from my ebook publisher, ebookit. The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
Courtesy of BtB’s stringer Jay. This post is also an open thread. I welcome my readers to post any comments or additional links relating to any space issues, even if unrelated to the links below.
Now available in hardback and paperback as well as ebook!
From the press release: In this ground-breaking new history of early America, historian Robert Zimmerman not only exposes the lie behind The New York Times 1619 Project that falsely claims slavery is central to the history of the United States, he also provides profound lessons about the nature of human societies, lessons important for Americans today as well as for all future settlers on Mars and elsewhere in space.
“Zimmerman’s ground-breaking history provides every future generation the basic framework for establishing new societies on other worlds. We would be wise to heed what he says.” —Robert Zubrin, founder of the Mars Society.
All editions are available at Amazon, Barnes & Noble, and all book vendors, with the ebook priced at $5.99 before discount. All editions can also be purchased direct from the ebook publisher, ebookit, in which case you don't support the big tech companies and the author gets a bigger cut much sooner.
Autographed printed copies are also available at discount directly from the author (hardback $29.95; paperback $14.95; Shipping cost for either: $6.00). Just send an email to zimmerman @ nasw dot org.
Today’s cool image will be unlike most cool images, in that we will begin not with the image but with the overview map to the right. The long meandering canyon at the center of this map is Nirgal Vallis, a 300-mile long canyon on Mars that eventually drains to the east into a much larger drainage system that runs south-to-north several thousand miles into the Martian northern lowland plains.
At first glance Nirgal Vallis invokes a river system. It starts in the west as several branches that combine to form a single major canyon meandering eastward until it enters that south-to-north system. To our Earth eyes, this canyon suggests it was carved by water flowing eastward, the many drainage routes combining as they flowed downhill.
Today’s the cool image, its location indicated by the white dot, tells us however that liquid water might not have been what created this canyon.
» Read more
Jared Isaacman
Capitalism in space: In a decision that is certain to send shock waves throughout NASA and the established aerospace industry, President-elect Donald Trump today announced that he has chosen billionaire and private astronaut Jared Isaacman to be his nominee for NASA administrator.
Isaacman quickly accepted the nomination.
Besides being a jet pilot with extensive experience in the aerospace industry, Isaacman has also commanded two space missions, financed out of his own pocket. Both missions used SpaceX’s Falcon 9 rocket and Resilience capsule. Both also pointedly avoided any involvement with NASA, spending several days in free Earth orbit instead of docking with ISS. The second mission achieved several major engineering milestones, testing the first privately built spacesuit during a spacewalk while also flying farthest from Earth since the 1970s Apollo missions.
These flights were part of Isaacman’s own long term space program, dubbed Polaris, with two more missions already in planning stages. The first would be another Dragon orbital mission in which Isaacman had tried to get NASA to shape as a Hubble repair mission. NASA declined. The second is intended as a manned mission around the Moon using SpaceX’s Starship.
That program will now likely get folded into NASA’s Artemis program, which we can all expect Isaacman to force major changes. For one thing, this is another blow to the future of SLS and Orion. As a very successful businessman Isaacman will look with great skepticism at this boondoggle.
For another, Isaacman’s markedly different experiences working with SpaceX versus NASA will likely encourage major bureaucratic changes at the space agency. It is almost certain that Isaacman’s manned flights avoided ISS in order to avoid its Byzantine red tape, that would have likely also blocked use of SpaceX’s spacesuit on a private spacewalk. NASA’s decision to reject Isaacman’s proposal to do a simple but very necessary Hubble repair mission will also likely influence his management of the agency. Isaacman is going to force NASA to depend on the private sector more. He is also likely to reduce the agency’s risk adverse mentality that while often reasonable is many times very counter-productive.
Unlike many of Trump’s other radical nominees, I would be very surprised if Isaacman is not confirmed quickly and with little opposition.
Whether Isaacman will still fly his two remaining private Polaris manned missions is at this moment unknown. Practically it would make sense to cancel them, since he will have much bigger fish to fry at NASA. Emotionally and politically however it would be truly spectacular to have NASA’s administrator fly in space, on a mission using no taxpayer funds. That more than anything would demonstrate the ability of freedom and private enterprise to get things done.
Leaving Earth: Space Stations, Rival Superpowers, and the Quest for Interplanetary Travel, can be purchased as an ebook everywhere for only $3.99 (before discount) at amazon, Barnes & Noble, all ebook vendors, or direct from my ebook publisher, ebookit.
If you buy it from ebookit you don't support the big oppressive tech companies and I get a bigger cut much sooner.
"Leaving Earth is one of the best and certainly the most comprehensive summary of our drive into space that I have ever read. It will be invaluable to future scholars because it will tell them how the next chapter of human history opened." -- Arthur C. Clarke
Capitalism in space: As part of the multi-billion dollar fund the Japanese government has allocated to encourage private enterprise by new Japanese startups, its space agency JAXA has now awarded a $32.5 million development contract to the startup ArkEdge Space to design and fly a GPS-type satellite in orbit around the Moon, thus demonstrating the technology.
Under the agreement, ArkEdge Space will plan and design the mass production and operation of micro-satellite constellations to lead the development of a next-generation Lunar Navigation Satellite System (LNSS), a vital component to the International “LunaNet” initiative driven by National Aeronautics and Space Administration (NASA), European Space Agency (ESA) and JAXA. LunaNet seeks to establish essential infrastructure to support sustainable lunar exploration and foster the growth of the lunar economy.
The real significance of this contract award is that it signals JAXA’s growing shift from designing, building, and owning everything to simply becoming the customer who gets what it needs from the private sector. The Japanese government had established that fund for this express purpose, but JAXA has shown a reluctance to proceed, as it directly threatens its turf. This award indicates that reluctance is finally being pushed aside.
Spaceports surrounding the Norwegian Sea
In a very sudden decision, the rocket startup Orbex, based in Great Britain, has “paused” its long-delayed work to develop a launch facility at the Sutherland spaceport in northern Scotland and instead decided to launch its first rockets from the competing SaxaVord spaceport on the Shetland islands.
Orbex says it is halting construction work on the £20 million spaceport and instead is mothballing the project, which has received a £14.6 million public investment package. The space company, which was to have made the Sutherland Spaceport its home port, will now launch its rockets carrying commercial satellites from another north spaceport – SaxaVord on Unst, Shetland.
According to the company’s CEO, it will retain its 50-year lease at Sutherland to give it “flexibility to increase launch capacity in the future.”
The company had originally hoped to launch its Prime rocket from Sutherland in 2022, but has been faced with red tape from the Civil Aviation Authority (CAA), which has still not issued a launch licence, even though the application was submitted almost three years ago. Orbex has also faced lawfare opposition from local activists as well as a major local landowner, billionaire Anders Povlsen, who is also a major investor in SaxaVord.
That last detail might help explain this decision. In private talks Orbex might have learned that the red tape and opposition would disappear if it switched to SaxaVord. The timing is also suggestive, as only a few days ago construction started on a new spaceport in Scotland, located on the island of North Uist.
All told, Orbex might have decided that the stars were aligned against it at Sutherland, and it was better to move. It now hopes to complete the first test launch of its Prime rocket from SaxaVord next year.
Today will be one of the busiest ever at spaceports worldwide. Already we have had two launches, with five more expected by this time tomorrow.
First, China launched a radar satellite, its Kuaizhou-1A solid-fueled rocket lifting off from the Xichang spaceport in the southwest of China. No word on where the rocket’s lower stages crashed in China.
Next, SpaceX placed another 24 Starlink satellites into orbit, its Falcon 9 rocket lifting off from Cape Canaveral in Florida in the early morning hours. The first stage completed a record 24th flight, the most flights of any Falcon 9 booster so far, landing on a drone ship in the Atlantic Ocean.
And we are only getting started today. If all goes right, by this time tomorrow Russia will have done a military launch from its Plesetsk spaceport, Arianespace will have launched a Vega-C from French Guiana, SpaceX will have completed two more Falcon 9 launches from Vandenberg and Kennedy, and India will have launched its PSLV rocket from its Sriharikota spaceport.
The leaders in the 2024 launch race:
125 SpaceX
58 China
15 Russia
13 Rocket Lab
American private enterprise still leads the rest of the world combined in successful launches 144 to 86, while SpaceX by itself leads the entire world, including American companies, 125 to 105.
According to a report yesterday by Bloomberg, SpaceX is now in talks to raise more private investment capital, based on a new and vastly increased valuation of the company, from $255 billion to $350 billion.
A so-called tender or secondary offering, through which employees and some early shareholders can sell shares, provides investors in closely held companies such as SpaceX a way to generate liquidity.
The amount the company hopes to raise by this tender is at present not known. In the past decade the company has raised about $12 billion in private capital in order to fund development of both its Starship/Superheavy rocket as well as its Starlink internet constellation. The latter however is already generating about $9 billion in revenue annually in the past two years, more than enough to fund the projects.
Embedded below the fold in two parts. This podcast, which aired almost a month ago, is late being posted here on Behind the Black because of a technical issue. John Batchelor got it fixed today, so for completeness I am posting it now.
To listen to all of John Batchelor’s podcasts, go here.
» Read more
Courtesy of BtB’s stringer Jay. This post is also an open thread. I welcome my readers to post any comments or additional links relating to any space issues, even if unrelated to the links below.
Click for original image.
Click for interactive map.
Since landing on Mars in 2021, the rover Perseverance has been exploring Jezero Crater, first the crater floor and then the delta that poured into the crater through a western gap.
Now, after three years of exploration and the drilling of 25 core samples, the science team is about to send Perseverance over the top of the crater’s western rim, to explore the very mountainous but potentially rich mining region beyond.
The blue dot on the overview map to the right indicates the rover’s present position, with the area covered by the panorama above, taken on November 26, 2024 by Perverance’s left navigation camera and cropped and annotated to post here, indicated by the yellow lines.
The red dotted line indicates the rover’s planned route. The black dotted line is a former plan that apparently has now been abandoned. It appears the science team really wants to check out Witch Hazel Hill, as well as reach the rim’s highest point to get views of its future travels. From an update posted yesterday:
Orbital views of Witch Hazel Hill suggest the area may contain layered and light-toned bedrock that likely record important information of the planet’s ancient climate. Prior to arriving at Witch Hazel Hill, the rover plans to pass through a high point known as Lookout Hill that will afford the team incredible views looking back into the crater, as well as get a glimpse westward of terrain far beyond Jezero.
The region beyond Jezero is hilly and rough. The views should be quite interesting.
The Spanish rocket startup PLD yesterday announced it has obtained a new $11.6 million loan that it plans to use to build its launch facility at the French-owned French Guiana spaceport.
The loan was issued by the Spanish governmment finance agency COFIDES, which comes on top of an earlier $43.8 million Spanish government grant. In addition, the company has gotten a $2.4 million grant from the European Commission, as well as a $1.37 million grant from the European Space Agency.
The company has also obtained a loan of $34 million from banks in Spain.
All told, the company has raised about $164 million, more than $58 million came from government agencies, with another $34 million from loans.
For whatever reason, PLD has found favor with the various governments in Europe, fueling its work. None of the other European rocket startups from Germany or Great Britain have been as lucky.
Click for original image of Chang’e-6 on the Moon
In a paper published in mid-November, Chinese scientists have concluded that — based on their analysis of the lunar samples returned by their Chang’e-6 spacecraft — the giant impact that created the 1,600-mile-wide South Pole-Aitken Basin on the Moon occurred about 2.83 billion years ago.
This conclusion is based both on the dating of the samples as well an analysis of the cratering rate on the Moon. It also suggests the landing site as well as Aitken basin were volcanically active for longer than previous predictions. Overall, scientists believe most volcanic activity on the Moon ceased around three billion years ago.
As noted in the paper, the near and far sides of the Moon are very different.
The Moon has a global dichotomy, with its near and far sides having different geomorphology, topography, chemical composition, crustal thickness, and evidence of volcanism. Volcanic eruptions flooded parts of the surface with lava, producing rocks known as mare basalts, which are more common on the nearside (4), where they cover ~30% of the surface compared to 2% of the farside.
The farside’s crust is also thicker, though under Aitken Basin the difference largely disappears.
This first precise dating for the far side is the first step for understanding why the Moon’s hemispheres are so different. Though many theories exist, none can be considered definitive because we so far have only one data point for the far side.
Based on records of two past eruptions approximately eighty years apart, astronomers had predicted that the binary star system T Coronae Borealis would erupt sometime in September 2024, brightening from magnitude 10 to as much as magnitude 2, making it one of the sky’s brighter stars for a short while.
That eruption however has so far not taken place.
“We know it has to happen,” astrophysicist Elizabeth Hays, who is watching T CrB every day using NASA’s Fermi gamma-ray space telescope, told Space.com in a recent interview. “We just can’t pin it down to the month.”
The unpredictability stems partly from limited historical records of T CrB’s outbursts. Only two such eruptions have been definitively observed in recent history: on May 12, 1866, when a star’s outburst briefly outshined all the stars in its constellation, reaching magnitude 2.0, and again on February 9, 1946, when it peaked at magnitude 3.0. These events appear to follow the star’s roughly 80-year cycle, suggesting that the next outburst may not occur until 2026. [emphasis mine]
The eruptions are thought to occur because the system’s denser white dwarf star pulls material from the lighter orbiting red giant. Over time that material accumulates on the surface of the white dwarf until it reaches critical mass, triggering a nuclear explosion that we see as the star’s brightening.
Astronomers have assumed this process is predictable, but in truth it really is not. For example, the star has brightened at other times, in 1938 and again in 2015, though not as much. These other brightenings suggest a great deal of uncertainty in the rate in which material accumulates, as well as how much is needed to trigger a nuclear burst.
Because of the possibility however of a burst at any time, astronomers have been poised eagerly now for months, observing the star regularly with the many orbiting telescopes that can observe it not only in optical wavelengths but in gamma, X-rays, and infrared. The latter capabilities didn’t exist in previous eruptions, and are now able to tell them things about the system that was impossible for earlier astronomers.
Assuming the eruption occurs at all. Despite the certainty of the astronomer’s quote highlighted above, there is no certainty here. This star system will do whatever it wants, despite the predictions of mere human beings.
Varda’s first capsule on the ground in Utah.
The U.S. Air Force last week awarded the reusable orbiting capsule company Varda a four-year $48 million contract for placing experimental hypersonic payloads on the capsule for testing during its re-entry through the atmosphere.
The four-year deal with AFRL [Air Force Research Laboratory], announced on Nov. 26, leverages Varda’s W-Series reentry capsules as platforms to test payloads at hypersonic speeds. The spacecraft are built on Rocket Lab’s Photon satellite bus,
…Varda’s next mission, W-2, is scheduled for early 2025. This mission is designed to showcase the Varda Hypersonic Testbed vehicle. The capsule will carry an AFRL-developed spectrometer payload named OSPREE (Optical Sensing of Plasmas in the Reentry Environment) to collect critical data during atmospheric descent.
Up until now Varda’s customers have been entirely focused on using the capsule to produce pharmaceuticals in weightlessness for sale back on Earth. This new contract provides it another and initially unexpected way to make money on the capsule’s capabilities.
China today successfully launched a communications satellite designed according to its state-run press to test new communication technologies, its Long March 3B rocket lifting off from its Xichang spaceport in southwest China.
No word on where the rocket’s lower stages and four strap-on boosters, all using toxic hypergolic fuels, crashed inside China.
The leaders in the 2024 launch race:
124 SpaceX
57 China
15 Russia
13 Rocket Lab
American private enterprise still leads the rest of the world combined in successful launches 143 to 85, while SpaceX by itself leads the entire world, including American companies, 124 to 104.
An evening pause: Uses nicely edited archival documentary footage and pictures to highlight to story told by the song, intercut with Lightfoot’s live performance in 1979.
Hat tip Wayne DeVette.
The Democratic Party for the past half century
While the conservative press is today going ga-ga over Joe Biden’s pardoning of his son Hunter yesterday — noting accurately that Biden’s action proved himself once again to be a liar and a fraud, having spent the last four years insisting he would never do such a thing while also insisting that “no one is above the law” — I think it more instructive to look at what some of the most rabid partisan leftists have been saying, before and after the election of Donald Trump.
You see, some of these partisan leftists are actually doing something I have not seen a partisan leftist do since before Bill Clinton was president — they are showing an ability to have an open mind.
Let’s begin with two members of a leftist podcast group dubbed the Young Turks that for years saw nothing good about any Republican and considering Donald Trump the epitomization of the devil himself. Anything Trump did was wrong. Everything Trump and the Republicans represented was evil and must be opposed blindly. During and after this presidential election campaign however two of the more noted members of this podcast, Ann Kasparian and Cenk Uygar, changed their tune, and did so in an astonishing way.
First there was Kasparian’s announcement in October that she has left the Democratic Party. Watch:
» Read more
Click for original image.
Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken by the Hubble Space Telescope as part of a study focused on looking at star formation in nearby galaxies. From the caption:
Evidence of star formation is scattered all around NGC 1637, if you know where to look. The galaxy’s spiral arms are dotted with what appear to be pink clouds, many of which are accompanied by bright blue stars. The pinkish colour comes from hydrogen atoms that have been excited by ultraviolet light from young, massive stars. This contrasts with the warm yellow glow of the galaxy’s centre, which is home to a densely packed collection of older, redder stars.
The stars that set their birthplaces aglow are comparatively short-lived, and many of these stars will explode as supernovae just a few million years after they’re born. In 1999, NGC 1637 played host to a supernova, pithily named SN 1999EM, that was lauded as the brightest supernova seen that year. When a massive star expires as a supernova, the explosion outshines its entire home galaxy for a short time. While a supernova marks the end of a star’s life, it can also jump start the formation of new stars by compressing nearby clouds of gas, beginning the stellar lifecycle anew.
This galaxy is one worth keeping an eye on for supernovae, since every one of those blue stars has the potential of erupting.
China today successfully launched for the first time its new Long March 12 rocket, lifting off from its coastal Wenchang spaceport and placing “two technology test satellites” into orbit.
The two-stage rocket, powered by burning kerosene and liquid oxygen, is notable as the first 3.8-metre-wide rocket launched so far by China, said Wu Jialin, an engineer with the Shanghai Academy of Spaceflight Technology under CASC, which developed the spacecraft.
Most Chinese rockets have a diameter of 3.35 meters, Wu told a press conference on site shortly after the launch was announced successful. “A wider body means the rocket can hold about 30 per cent more propellant, giving it much enhanced carrying capacity,” he said.
For comparison, the Falcon 9 has a diameter of 3.7 meters, though its payload fairing is wider. China intends to use this new rocket to launch its own large satellite constellations to compete with SpaceX.
The leaders in the 2024 launch race:
124 SpaceX
56 China
15 Russia
13 Rocket Lab
American private enterprise still leads the rest of the world combined in successful launches 143 to 84, while SpaceX by itself leads the entire world, including American companies, 124 to 103.
Construction of a third spaceport in Scotland has now begun, its location on the northwest coast of the island of North Uist (as shown on the map to the right), with its plans to serve suborbital launches initially.
The Highlands and Islands Enterprise, a Scottish government agency focused on regional development, has allocated £947,000 for the construction of the site’s enabling infrastructure. Additionally, the Comhairle is contributing £675,000 from its 2023-2028 capital programme. The total cost of the enabling works project is estimated to be £2.6 million.
After the construction of the enabling infrastructure is complete, which is expected to occur by Spring 2025, a private sector operator will take over to complete the second phase of construction and manage the spaceport.
According to the Wikipedia page for this area on North Uist, the project was first proposed in 2019, and was then hoping to attract orbital launches. Subsequent opposition by activists slowed development and likely reduced the project from orbital to suborbital, at least for now.
SpaceX early today successfully completed a launch for the National Reconnaissance Office (NRO), its Falcon 9 rocket lifting off from Vandenberg in California.
The broadcast by SpaceX began after launch, had degraded visuals, and cut off immediately after the first stage, on its very first flight, touched down successfully on a drone ship in the Pacific. Very little confirmed information was released about the payload, though according to this story that payload included 20 Starlink satellites as well as an additional payload for NRO. It is also possible the Starlink satellites were that NRO payload, being the Starshield military version of Starlink.
The leaders in the 2024 launch race:
124 SpaceX
55 China
15 Russia
13 Rocket Lab
American private enterprise now leads the rest of the world combined in successful launches 143 to 83, while SpaceX by itself leads the entire world, including American companies, 124 to 102.
SpaceX tonight successfully placed another 24 Starlink satellites into orbit, its Falcon 9 rocket lifting off from Cape Canaveral in Florida.
The first stage completed its sixth flight, landing on a drone ship in the Atlantic.
The leaders in the 2024 launch race:
123 SpaceX
55 China
15 Russia
13 Rocket Lab
American private enterprise now leads the rest of the world combined in successful launches 142 to 83, while SpaceX by itself leads the entire world, including American companies, 123 to 102.
An evening pause: From the 1933 film She Done Him Wrong. And yes, the young guy you see is Cary Grant. Sadly the print here is old and fuzzy, but a newer reprint is not available on line.
Hat tip Judd Clark.
Courtesy of BtB’s stringer Jay. This post is also an open thread. I welcome my readers to post any comments or additional links relating to any space issues, even if unrelated to the links below.
Russia today successfully launched a new radar Earth-observation satellite, its Soyuz-2 rocket lifting off from its Vostochny spaceport in the far east.
The leaders in the 2024 launch race:
122 SpaceX
55 China
15 Russia
13 Rocket Lab
American private enterprise still leads the rest of the world combined in successful launches 141 to 83, while SpaceX by itself leads the entire world, including American companies, 122 to 102.
Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken on October 2, 2024 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). The white dot in the overview map above marks the location, inside the chaos terrain of Deuternilus Mensae and part of the 2,000-mile-long mid-latitude Martian strip I label “glacier country,” because practically every image of every part of its landscape has glacial features. For example, the splash apron around the picture’s largest crater as well as the material within it all suggest some form of glacial activity and near-surface ice.
The scientists label what they see here as “Mesas in Small Craters.” These features are located in a low flat plain that geologists think was created when the ground eroded away, leaving behind scattered high plateaus that indicate the previous surface elevation. The geological map [pdf] of this plain describes it as follows:
Smooth, relatively featureless materials with regions of variable albedo north of continuous cratered highlands; exhibits scattered clusters of small circular to irregular knobs.
Based on the many accumulated photos from MRO, the general conclusion is that we are looking at a sheet of ice/dirt and covered by a thin dust layer that acts to protect that ice from sublimating away. When wind blows that dust off and the summer sun hits that near-surface ice, however, it does sublimate in bursts, which thus provides an explanation for the erosion that caused these low featureless plains.
As for these strange terraced mesas inside these distorted hollows, my guess is that the mesas predate the icesheet and are made of material with less ice impregnated within it. As that ice sublimates away it creates the craters within which the mesas remain. The terraces suggest a earlier series of geological sedimentary history.
