Author: Robert Zimmerman

Momentus reports successful use of its new water-based thrusters on its orbiting Vigoride-5 tug

8:55 pm

The orbital tug startup Momentus on March 23, 2023 reported the successful use of its new water-based thrusters on its orbiting Vigoride-5 prototype tug, proving the design works.

The Reaction Control System operates using the same propellant and tank with water as the Vigoride spacecraft’s primary MET propulsion system. The MET is designed to use water as a propellant and produce thrust by expelling extremely hot gases through a rocket nozzle. Unlike a conventional chemical rocket engine, which creates thrust through a chemical reaction, the MET is designed to create a plasma and thrust using microwave energy. When operational, the MET will be used to raise the orbital altitude and inclination of Vigoride-5.

Essentially this is a variation of an ion engine. The thrust will be low, but very efficient. The thrusters can therefore fire for a very long time, building up accelerations infeasible for chemical engines, and thus allowing the tug to significantly change the orbits of satellites in ways that was previously impossible.

This release came out the day before NASDAQ announced that Momentus has six months to raise the price of its stock above one dollar or be delisted from the stock exchange. Since its release, the stock price rose from $0.54 to $0.63, still below a dollar but going in the right direction, despite the NASDAQ announcement.

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NASDAQ gives two more space companies delisting warning

10:25 pm

NASDAQ yesterday told the space companies Momentus and Spire they have six months to get their stock price over $1 or the stock exchange will delist each.

Small satellite builder and data specialist Spire Global received a notice from the New York Stock Exchange, while spacecraft delivery company Momentus received a notice from the Nasdaq. Under the respective exchanges’ compliance rules, the companies have 180 days, or about six months, to get their stock prices back above $1 a share.

Spire’s stock closed at 69 cents a share on Friday, having first slipped below $1 a share on Mar. 7. Momentus’ stock closed at 63 cents a share, slipping below $1 a share on Feb. 7.

Both companies now join Astra under the same threat. Both also have indicated they will consider a reverse-stock split, combining stocks to reduce the total number in order to bring the price above one dollar.

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India launches 36 OneWeb satellites

9:09 pm

India’s space agency ISRO tonight successfully launched 36 OneWeb satellites using its LVM-M3 rocket, the largest version of its GSLV family of rockets.

This launch completes OneWeb’s constellation, with 618 satellites now in orbit, allowing them to now offer internet access worldwide in competition with Starlink. After Russia broke its contract and confiscated 36 OneWeb satellites, the company contracted SpaceX and ISRO to launch the satellites necessary to complete the constellation, with SpaceX doing three launches and ISRO two.

This was India’s second launch in 2023. The leaders in the 2023 launch race remain the same:

20 SpaceX
11 China
5 Russia
3 Rocket Lab

American private enterprise still leads China 23 to 11 in the national rankings, and the entire world combined 23 to 19. SpaceX by itself now trails the entire world, including other American companies, 20 to 22.

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Ancient Martian landslides

5:45 pm

Ancient Martian landslides
Click for original image.

Cool image time! The picture to the right, rotated, cropped, reduced, and sharpened to post here, was taken on December 23, 2022 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). The image was labeled “Landslides in Orson Welles Crater” because the full photo shows at least two large and obvious slides, with the biggest shown to the right.

These avalanches are likely ancient because both have craters on them suggesting the material has not moved for a very long time. Yet when both flowed they did so almost like mud, the material moving downhill almost in a single blobby mass. Both have this look, as do many Martian landslides, which I think is why the scientists usually label them mass wasting events.
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The invulnerability of today’s academic blacklist culture

2:22 pm

Tirien Steinbach: in favor of censorship and mob rule
Stanford’s Tirien Steinbach:
in favor of censorship and mob rule

They’re coming for you next: In order to best understand how difficult it will be to regain the free and open society that was once the United States, we need only look at recent events at the Stanford Law School.

On March 9, 2023 a mob of students and faculty, led by Tirien Steinbach, the school’s diversity, equity and inclusion dean, shouted down U.S. Court of Appeals Judge Kyle Duncan when he tried to give a lecture about the law for the school’s chapter of the Federalist Society.

You can watch a video of this mob action at the link, where Steinbach actually took the podium away from Duncan to order to give a speech defending the mob and agreeing with their effort to silence him.

The story has gotten ample coverage in the press, including the general reaction from outside the school. For example, in Texas and in California action has been proposed to bar the students involved from getting law licenses.

The law school itself initially responded very weakly, simply sending a letter of apology to Duncan.
» Read more

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Blue Origin releases results of investigation into New Shepard flight failure

11:04 am

Blue Origin today released by email its results of its investigation into the New Shepard flight failure that occurred in September 2022, when the launch abort system activated soon after launch and released the capsule early so that it could return safely to Earth.

[T]he MIT [investigation team] determined the direct cause of the mishap to be a structural fatigue failure of the BE-3PM engine nozzle during powered flight. The structural fatigue was caused by operational temperatures that exceeded the expected and analyzed values of the nozzle material. Testing of the BE-3PM engine began immediately following the mishap and established that the flight configuration of the nozzle operated at hotter temperatures than previous design configurations. Forensic evaluation of the recovered nozzle fragments also showed clear evidence of thermal damage and hot streaks resulting from increased operating temperatures. The fatigue location on the flight nozzle is aligned with a persistent hot streak identified during the investigation.

The MIT determined that design changes made to the engine’s boundary layer cooling system accounted for an increase in nozzle heating and explained the hot streaks present. Blue Origin is implementing corrective actions, including design changes to the combustion chamber and operating parameters, which have reduced engine nozzle bulk and hot-streak temperatures. Additional design changes to the nozzle have improved structural performance under thermal and dynamic loads.

In other words, the company had made some design changes to the engine prior to launch, and these caused the hot spots that destroyed the nozzle.

The company’s email says it is fixing this issue and plans to launch “soon”, but issued no date.

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Hubble spots long term seasonal changes on Uranus

10:20 am

Uranus as seen by Hubble in 2014 and 2022
Click for original image.

Using images of Uranus taken eight years apart by the Hubble Space Telescope, astronomers have detected significant seasonal changes in the atmosphere of the gas giant, caused by its unusual sideways rotation.

The two pictures to the left, realigned and reduced to post here, show the changes. If you look closely you can see the planet’s ring system and its shift to almost face on at present.

[top] — This is a Hubble view of Uranus taken in 2014, seven years after northern spring equinox when the Sun was shining directly over the planet’s equator, and shows one of the first images from the OPAL program. Multiple storms with methane ice-crystal clouds appear at mid-northern latitudes above the planet’s cyan-tinted lower atmosphere. Hubble photographed the ring system edge-on in 2007, but the rings are seen starting to open up seven years later in this view. At this time, the planet had multiple small storms and even some faint cloud bands.

[bottom] — As seen in 2022, Uranus’ north pole shows a thickened photochemical haze that looks similar to the smog over cities. Several little storms can be seen near the edge of the polar haze boundary. Hubble has been tracking the size and brightness of the north polar cap and it continues to get brighter year after year. Astronomers are disentangling multiple effects – from atmospheric circulation, particle properties, and chemical processes – that control how the atmospheric polar cap changes with the seasons. At the Uranian equinox in 2007, neither pole was particularly bright.

To really understand the long term climate of Uranus will likely take centuries, since its year lasts 84 Earth years. Since the beginning of space exploration, we have only had now about forty years of good imagery of the planet, and even that has been sporadic and very incomplete.

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Sierra Space pops another inflatable test space station module

9:56 am

Proposed Orbital Reef space station
Proposed Orbital Reef space station

Sierra Space announced yesterday that it had successfully completed its fourth test to failure of a one-third scale prototype inflatable space station module, dubbed LIFE, with work on the full scale module expected to begin next year and leading to the launch of its private commercial space station sometime later this decade.

In February, Sierra Space performed a month-long Accelerated Systematic Creep (ASC) test on LIFE – the first milestone in its 2023 testing campaign. Engineers loaded a one-third-scale version of the inflatable habitat with a sustained amount of pressure over an extended period until it failed. Per NASA’s recommended guidelines for inflatable softgoods certification, the test reached its goal of generating an additional data point – pressure and time to burst – which can be used to estimate the life of the primary pressure shell structure.

“Our testing campaign has demonstrated that our LIFE habitat pressure shell design has a predicted life of far greater than 60 years – or 525,600 hours – based on Sierra Space’s 15-year on-orbit life requirement and the applied 4x safety factor,” said Sierra Space Chief Engineer for LIFE, Shawn Buckley. “We are obviously simulating pressures well in excess of the norm.”

You can view video of the test here. The failure was so intense that it also blew up the test shack.

Sierra Space is part of a partnership with Blue Origin and others to build the Orbital Reef space station, one of four such stations with contracts with NASA. Sierra Space is building the station’s modules, while Boeing is providing the Starliner capsule for transportation. Blue Origin is supposed be providing larger modules and the New Glenn rocket for transportation, but the development of both continues to lag.

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Starliner’s first manned mission to ISS delayed again

9:36 am

According to a tweet by a NASA official, the first manned mission to ISS of Boeing’s Starliner capsule, carrying two NASA astronauts, has been delayed again, from the planned late April launch to sometime during the summer.

No reasons for the delay were given, as yet. The second link notes however that a schedule conflict at ULA, which is launching Starliner on its Atlas-5 rocket, might be part of the reason.

A launch in late April [of Starliner on the Atlas-5] would have put it in conflict with the inaugural launch of United Launch Alliance’s Vulcan Centaur rocket, currently scheduled for as soon as May 4. Vulcan and Atlas use the same launch pad at Cape Canaveral Space Force Station, and ULA has been conducting tests of the Vulcan rocket on that pad. It has not shared updates on the status of the Atlas 5 used for Starliner.

This conflict might also explain why Starliner itself has not yet been fueled, since Boeing officials have said they want to do this within 60 days of launch to avoid the same kind of valve leaks that delayed the second unmanned demo mission for almost a year.

Starliner itself is years behind schedule, a long delay that has cost Boeing an enormous amount of income. First, the problems during the first unmanned demo flight in December 2019 forced the company to do a second unmanned demo flight, on its own dime costing about $400 million. That second flight was then delayed because of those valve issues. All the delays next cost Boeing income from NASA, as the agency was forced to purchase many manned flights from SpaceX that it had intended to buy from Boeing.

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Rocket Lab and SpaceX successfully launch

9:10 am

There were two launches since yesterday, both American, both launching commercial satellites.

First, Rocket Lab put two Black Sky commercial Earth observation smallsats into orbit, using its Electron rocket launching from New Zealand. This was Rocket Lab’s second launch in less than a week.

Next, SpaceX put 56 Starlink satellites into orbit, launching from Cape Canaveral. The Falcon 9 rocket’s first stage completed its 10th flight, landing successfully in a drone ship in the Atlantic.

The leaders in the 2023 launch race:

20 SpaceX
11 China
5 Russia
3 Rocket Lab

American private enterprise now leads China 23 to 11 in the national rankings, and the entire world combined 23 to 18. SpaceX in turn trails the entire world combined, including American companies, by only 20 to 21.

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Where the flood lava of two gigantic Martian volcanoes meet

5:46 pm

Where the flood lava of two gigantic Martian volcanoes meet
Click for original image.

Today’s cool image illustrates once again the importance of looking not simply at the picture but at the surrounding larger context in order to understand the Martian features within the photograph.

The photo to the left, cropped, reduced, and sharpened to post here, was taken on January 31, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). The location is at 26 north latitude, so it is in the dry equatorial regions. It shows what appears to be a large Martian flood lava plain, with at least two different flood lava events appearing to flow to the northeast, with the second only partly covering the first.

From this high resolution image it seemed probable that the source of the flow was from the southwest, an assumption that at first glance is strengthened by the overview map below.
» Read more

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Today’s blacklisted American: Black DEI administrator fired by college for demanding accuracy and color-blind policies

1:18 pm

Tabia Lee
Tabia Lee

They’re coming for you next: Tabia Lee, the faculty director for the Office of Equity, Social Justice, and Education [OESE] at De Anza College in California, was denied tenure and fired from her job when she repeatedly demanded historical accuracy and color-blind policies from both her department and the rest of the college.

“Historical accuracy and color-blind policies” from a modern college run by leftists? It is to laugh.

Tabia Lee is a black woman who had been an adjunct professor at De Anza when she got the job to run part of the OESE department.

After years of working as a middle-school teacher and an adjunct professor, and founding a network to help minority teachers attain national board certification, Lee was excited get a tenure-track position at De Anza, where her job includes designing workshops to promote inclusion. “I researched them, and I thought we had similar values around diversity, equity and anti-racism,” she said. “I was selected, and I was like, wow, this is a dream come true.”

Instead, Lee found herself constantly harassed and slandered because she tried to bring to her work an even-handed philosophy that attempted to deal with the problems of racial conflict fairly. For example, when Jewish students and faculty members told her they had experienced anti-Semitism on campus, Lee tried to organize a campus event to discuss the problem.
» Read more

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Ingenuity completes 48th flight on Mars

11:33 am

Overview map
Click for interactive map.

On March 21, 2023 the Mars helicopter Ingenuity successfully completed its 48th flight on Mars, flying 1,305 feet for 149.9 seconds with a top altitude of 39 feet. As has now become routine on all the recent flights, the distance and time in the air exceeded slightly the planned amounts, probably because Ingenuity needed slightly more time to find a good landing spot.

The link provides a very short movie created from images looking down during the flight.

The map to the right provides the context. The green dot and line indicates Ingenuity’s new position and flight path respectively. The blue dot marks Perseverance’s present location, a spot the mission planners had previously targeted as a prime place for obtaining core samples. The red dotted line shows the rover’s planned route.

Since the science team is now using Ingenuity for scouting purposes, its turn towards the rim of Belva Crater suggests they are considering this detour for Perseverance as well.

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NASA engineers continue to struggle to save the Flashlight lunar probe

10:30 am

In an update today, NASA reports that engineers continue to troubeshoot the failure of the experimental thrusters on the Lunar Flashlight cubesat, in an effort to improvise a way to get the probe into lunar orbit.

Shortly after launch on Dec. 11, 2022, the operations team for NASA’s Lunar Flashlight determined that three of the four CubeSat’s thrusters were underperforming. This cast doubt on whether the mission could complete its stretch science goal of detecting surface ice at the Moon’s South Pole. After analyzing the situation, team members at NASA’s Jet Propulsion Laboratory and Georgia Tech arrived at a creative maneuvering technique that would use the one fully-functioning thruster to get into planned orbit. But when attempting the modified maneuvers in January, that thruster also experienced a rapid loss in performance and the team determined that Lunar Flashlight would likely be unable to reach its planned near-rectilinear halo orbit around the Moon.

After further troubleshooting, the operations team has been working on ways to restore partial operation of one or more thrusters to keep the spacecraft within the Earth-Moon system. They have had some success but continue to try new things to clear the suspected obstructions in the thruster fuel lines. They have until the end of April to generate the required thrust to preserve the opportunity to allow for monthly flybys of the lunar South Pole.

Though it increasingly appears Lunar Flashlight will not make lunar orbit, the mission is not a failure, since it was first and foremost an engineering mission testing a variety of new cubesat technologies, including the failed thrusters. Their failure and the efforts by engineers to recover them is important data for developing better cubesat thrusters on future such planetary probes.

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SpaceX might get investment capital from Saudi and UAE investors

10:23 am

According to several reports in the business press, SpaceX is presently negotiating with investment companies in Saudi Arabia and the United Arab Emirates (UAE) to possibly provide additional investment capital to the company.

Citing two individuals reportedly familiar with the matter, The Information noted that Saudi Arabia’s Water and Electricity Holding Company, Badeel, and the United Arab Emirates’ Alpha Dhabi are participating in the funding round. Morgan Stanley is reportedly organizing the investment effort.

At present it is unknown how much would be invested. It is also unclear if this foreign investment in an American rocket company can pass muster with the U.S. State Department.

SpaceX has already raised about $10 billion in private investment capital as well as $4 billion from NASA for the development of Starship/Superheavy.

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Italy funds development by Avio of smallsat rocket and methane engine

10:13 am

In a move that might eventually separate Italy from the European Space Agency’s (ESA) Arianespace commercial division, the Italian government on March 13, 2023 announced that it has committed $308 million to the Italian company Avio to develop both a methane-fueled engine and the smallsat rocket to go with it.

The money will be used by Avio on two projects, one to develop an upgraded version of its M10 methane-fueled engine that has already completed two dozen static fire tests, and the other to develop the smallsat rocket, with a targeted first launch in 2026.

While the investment is officially in partnership with the ESA, its wholly-Italian nature suggests in the end it will not be part of Arianespace, but function as an independent competing rocket operated and owned by Avio, which is also the company that developed Arianespace’s Vega family of rockets.

If Italy allows Avio to pull free of ESA and operate as a separate competing rocket company, it will do Europe a favor. Right now the monopolistic nature of ESA is preventing it from competing successfully in the new commercial launch market. Having separately owned and competing private companies will only energize this European industry, which has generally been moribund for years.

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First set of SpaceX’s second generation Starlink satellites experiencing issues

9:57 am

According to a tweet from Elon Musk yesterday, the first set of 21 larger second generation Starlink satellites, launched on February 27, 2023 by a Falcon 9 rocket, have experiencing “some issues.”

Some sats will be deorbited, others will be tested thoroughly before raising altitude above Space Station.

More information here.

Starting around March 15, their orbital altitude started to decrease at varying rates: most gradually, but at least two more steeply, descending to about 365 kilometers. All 21 remain in orbit, but that unusual behavior prompted speculation of problems with the satellites.

The second set of new Starlink satellites is scheduled for launch no earlier than March 30, 2023, but expect that launch to be delayed in order for SpaceX engineers to troubleshoot these issues and then apply what they have learned on the new satellites.

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Russia launches military satellite

9:50 am

Using its Soyuz-2 rocket, Russia today launched a classified military satellite into orbit, lifting off from its Plesetsk spaceport in northern Russia.

The rocket flew north over the Arctic, with its first and second stages falling into the ocean.

The leaders in the 2023 launch race:

19 SpaceX
11 China
5 Russia
2 Rocket Lab

American private enterprise still leads China in launches 21 to 11 in the national rankings, and the entire world combined 21 to 18. SpaceX now trails the entire world combined, including American companies, 19 to 20.

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Second stage on Relativity’s first launch fails to fire

9:36 am

The first test launch of Relativity’s 3D rocket, Terran-1, achieved the mission’s minimum goals, with the first stage performing exactly as planned and the 3D-printed rocket successfully completing engine cut-off and stage separation.

At that point the second stage engine failed to fire, and the upper stage fell into the ocean.

I have embedded the live stream from last night below. The company had made it clear that their number one goal for this flight was getting that 3D-printed rocket through max-q, the time when the atmospheric pressures on the rocket are their greatest. In this area the launch was a success.

This was also the first American launch of a methane-fueled rocket, and it was fascinating seeing the difference in the rocket’s plumes from other fuel types. Terran-1’s engine plumes were a clear distinct blue, quite different from the white and smokey plumes produced by solid-fueled and kerosene-fueled rocket engines, and the almost invisible plume of space shuttle’s hydrogen-fueled engines.

As yet, no methane-fueled rocket has reached orbit, though two Chinese companies and Relativity have tried. SpaceX will try itself when it launches Superheavy/Starship.
» Read more

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Nena – 99 Luftballons

6:01 pm

An evening pause: This pretty 1983 German pop song so perfectly predicts the Biden administration’s silly overreaction to the Chinese spy balloons last month, and the really dangerous consequences that could have resulted.

The lyrics of the original German version tell a story: 99 balloons are mistaken for UFOs, causing a military General Officer to send pilots to investigate. Finding nothing but balloons, the pilots put on a large show of fire power. The display of force worries the nations along the borders and the war ministers on each side encourage conflict to grab power for themselves. In the end, a cataclysmic war results from the otherwise harmless flight of balloons and causes devastation on all sides without a victor.

Hat tip Jay, who is still off in the tropics doing ham radio stuff.

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Confused glaciers in a Martian crater

5:59 pm

Confused glaciers in a Martian crater
Click for original image.

Cool image time. The picture to the right, cropped to post here, was taken on February 2, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO), and shows a strangely blobby crater in the northern mid-latitudes where glacial features are frequently found inside craters.

In this case however the glacier seems very confused. As this is in the northern hemisphere, you would expect glacial material to survive on the north-facing southern interior slopes of the crater, where there is year-round less sunlight. The mottled eroded terrain in the south part of the crater floor suggests this. However, the crater also clearly has a terraced glacier on its south-facing northern interior slopes.

Why has the glacial material survived in both places, but not in the center of the crater?

In addition, there is that strange roughly circular feature attached to the south side of the crater. What formed it? Is it a glacier on the plains surrounding the crater? Or are we looking at volcanic material?

This crater is also unique. The crater just to its southwest (partly seen in the cropped image above), is a much more typical glacial-filled mid-latitude crater, its interior material more evenly distributed and its circular rim only slightly distorted.
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Pushback: Doctors blacklisted by government for disagreeing on its COVID mandate policies now fighting back

2:04 pm

Written by many of the doctors of the Norfolk Group
Correct from the start despite government censorship,
and written by many of the same doctors of the Norfolk Group

Bring a gun to a knife fight: Eight high-ranking doctors, many who were censored and blacklisted by the government and big social media outlets for daring to disagree with the government’s lockdown, masking,, and COVID jab mandates, have now issued a detailed report, dubbed the Norfolk Group report, outlining the many errors of those policies, as well as offering what the scientists call “a blueprint” for moving forward. From their introduction:

In separate chapters we summarize key background information and propose specific questions about failures to protect older high-risk Americans, about school closures, collateral lockdown harms, lack of robust public health data collected and/or made available, misleading risk communication, downplaying infection-acquired immunity, masks, testing, vaccine efficacy and safety, therapeutics, and epidemiological modeling.

We chose not to discuss economic issues, although we recognize that negative effects on the economy have long-term negative effects on public health. We have also chosen not to engage in issues regarding media handling of the pandemic, nor questions of how, when and why the SARS-CoV-2 virus originated. Public health responses to a pandemic are devised and implemented independently of viral origin.

» Read more

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No ice inside permanently shadowed crater near Moon’s south pole?

12:44 pm

Marvin crater as seen by Shadowcam
Click for original image.

Overview map

Using a camera on South Korea’s lunar orbiter Danuri, dubbed Shadowcam and designed to look into the permanently shadowed craters at the Moon’s poles, scientists have taken an image that sees into the forever dark region of one such crater.

The picture to the right, released on March 13, 2023 by the Shadowcam science team, is of the crater Marvin, located about 16 miles to the east of the south pole. The pink outline indicates the area that is thought to be permanently shadowed.

The second image to the right provides a wider view of the south pole region, with the craters labeled and outlined by the green lines. The orange lines mark permanently shadowed areas. The white box indicates the approximate area covered by the Shadowcam picture. One of the candidate landing sites for Starship, as part of NASA’s Artemis program, is the eastern rim of Shackleton, essentially at the south pole itself.

Previous data suggests that ice should be found in those permanently shadowed areas, because other orbiters have detected evidence of hydrogen there. The Shadowcam picture above however shows nothing that strongly suggests the presence of ice, unless that darker flat area on the floor of the crater is ice-infused dust. If so however, it is quite ancient and solid, based on the presence of several craters within it.

The press release makes no mention of this question, probably because the scientists are still analyzing the data. This first look however suggests the ice is not there, or is in a form that is going to require a lot of processing to extract the water from it.

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Samples from Ryugu found to contain uracil, one of the four nucleobases in RNA

11:02 am

Japanese researchers analyzing the samples returned by Hayabusa-2 from the rubble-pile asteroid Ryugu have identified the molecule uracil, one of the four nucleobases that form the molecule RNA.

Hayabusa 2 collected 5.4 grams from two spots on Ryugu and delivered them to Earth on December 6, 2020. Early studies showed the samples contained many organic compounds. That led Oba’s group to analyze two 10-milligram samples using the same sensitive technique they had used earlier on meteorites. The technique can detect nucleic acid bases at levels down to parts per trillion in small samples.

Now, they report in Nature Communications that uracil is present at a level of parts per billion in both Ryugu samples. While this concentration is different than they’d previously found in meteorites, Oba says that might be because the parent bodies of the meteorites and of Ryugu underwent different levels of aqueous alteration and other processes. They also detected niacin (vitamin B3) as well as other organic molecules, but they didn’t find any other nucleobases.

RNA is formed from four nucleobases, uracil, adenine, cytosine, and guanine. To form DNA, the fundamental building block of life, uracil is replaced by thymine.

This data reinforces other data that suggests the formation of these essential molecules for life is relatively common and easy, at least in our solar system.

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