Tag: engineering

A spray of Martian meteorites

12:27 pm

A spray of small secondary impacts
Click for full image.

Cool image time! The photo to the right, cropped and reduced to post here, was taken on October 26, 2020 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It is what the camera team calls a “terrain sample,” meaning it was not specifically requested by a researcher but was instead chosen by the camera team because they need to regularly take images to maintain the camera’s temperature. When they do this, they try to pick a location that hasn’t been photographed in high resolution previously, and that might have some interesting features. Sometimes the photo is boring. Sometimes they hit pay dirt.

In this case, the photo captured an small impact crater, about 1,300 feet across, surrounded by a spray of secondary impacts. The color portion of the image shows what I suspect are dust devil tracks cutting across a surface that, because of its blue tint, is either rough or has frost or ice within it. At 48 degrees north latitude, the possibility of the latter is high, especially because this location is northwest of the Erebus mountains, where SpaceX has its prime Starship candidate landing zone and where scientists suspect ice is readily available very close to the surface. The overview map below shows this context.
» Read more

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LRO looks at Yutu-2

9:40 am

Yutu-2's travels on the Moon through October 2020
Click for full image.

The new colonial movement: The Lunar Reconnaissance Orbiter (LRO) science team today released an update of the travels of China’s Yutu-2 lunar rover, presently operating on the far side of the Moon.

The photo to the right, reduced and annotated to post here, shows the rover’s present position, having traveled about 1,650 feet to the northwest in the 22 months since landing. The goal, according to Yutu-2’s science team, is to get the rover beyond the present ejecta field of debris thrown from a large impact to the north, and reach a basalt covered region about a mile away. At the pace they are setting, about 100 feet per lunar day, it is going to take them about another three years to get there. Whether the rover will last that long is the question, but I suspect they are hopeful, based on the almost two years of operations so far.

If you go to the link you can also see a short movie showing month-by-month where the rover ended up when it shut down for each long lunar night.

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Chang’e-5 lands on Moon

9:09 am

The new colonial movement: According to official Chinese reports, Chang’e-5 has successfully soft-landed on the Moon in preparation for its gathering of samples to bring back to Earth.

The Chang’e 5 lander began final descent at 09:58 EST (14:58 UTC) with an expected touchdown 15 minutes later at 10:13 EST (15:13 UTC).

All broadcasts of the event were abruptly stopped just before the landing burn was to begin — throwing the mission into question with CCTV in China at first saying landing coverage would resume at 21:00 EST — an 11 hour delay to the landing. Minutes later, official sources — via social media — proclaimed a successful landing.

Blocking a broadcast like this is very typical of totalitarian governments, and totalitarian societies. Think about that the next time Youtube or Google or Facebook or Twitter or an American university silences speech they don’t like.

As for the lander, all other news reports that I have so far found provide no further details. It appears that all we know comes from a single sentence announcement of success from the Chinese press.

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Arecibo’s suspended instrument platform has collapsed onto dish

8:59 am

The suspended 900-ton instrument panel of the Arecibo Observatory in Puerto Rico collapsed early today, crashing down onto the radio telescope’s dish.

[Ramon Lugo, director of the Florida Space Institute at the University of Central Florida] says no one was near the dish when the platform fell. But he did not have all the details on how the structure came down. He believes it was because of a failure of one of the remaining cables connecting the platform to one of three support towers. These cables were carrying extra stress following the two previous failures. And since the Thanksgiving holiday, Lugo says, wires were breaking in these remaining cables at a rate of about one a day. He says he told NSF the structure only had a week or two remaining before it would collapse.

They plan on figuring out exactly what caused the collapse, but that is only to facilitate the planned decommissioning and removal of the telescope.

To me, this is another indicator of the arriving dark age. Earlier American generations would not only have never allowed this facility to fall into such disrepair, they would have never considered dismantling it. Instead, they would be planning how to make it bigger and better. Not today.

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New problem found on Orion that could delay its launch by a year

12:11 am

The failure of a power unit on the Orion capsule slated to fly on SLS’s first test flight late in ’21 could delay that test flight by as much as an additional year.

Replacing the PDU isn’t easy. The component is difficult to reach: it’s located inside an adapter that connects Orion to its service module — a cylindrical trunk that provides support, propulsion, and power for the capsule during its trip through space. To get to the PDU, Lockheed Martin could remove the Orion crew capsule from its service module, but it’s a lengthy process that could take up to a year. As many as nine months would be needed to take the vehicle apart and put it back together again, in addition to three months for subsequent testing, according to the presentation.

Lockheed has another option, but it’s never been done before and may carry extra risks, Lockheed Martin engineers acknowledge in their presentation. To do it, engineers would have to tunnel through the adapter’s exterior by removing some of the outer panels of the adapter to get to the PDU. The panels weren’t designed to be removed this way, but this scenario may only take up to four months to complete if engineers figure out a way to do it.

A third option is that Lockheed Martin and NASA could fly the Orion capsule as is. The PDU failed in such a way that it lost redundancy within the unit, so it can still function. But at a risk-averse agency like NASA, flying a vehicle without a backup plan is not exactly an attractive option. It’s still not clear what went wrong inside the unit, which was tested before it was installed on the spacecraft, according to a person familiar with the matter.

None of these options are good. The first two will certainly delay the planned November 2021 launch, which by the way is already four years behind schedule. The third will risk a failure of the mission, which though unmanned would certainly lead to further delays in the manned mission expected one or two years later.

That they don’t know why the unit failed and cannot fix it easily speaks very badly to the design of Orion and SLS. Compare this with SpaceX, which in the past month has demonstrated it can in only days switch out engines on both its commercial Falcon 9 rocket and its new next generation Starship rocket. Moreover, SpaceX has demonstrated repeatedly that once they identify an issue they move immediately to understand it and fix it.

With NASA, Orion, and Orion’s contractor Lockheed Martin, such flexibility and agility appears all but impossible. They have designed a monster that cannot be fixed easily, cannot launched quickly, and costs an ungodly amount of money.

I increasingly believe that Starship will reach orbit before SLS/Orion, even though the latter has been in development for almost three times longer, and will cost 25 times more.

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A place on Mars where lakes, snowfall, and rivers once existed

2:19 pm

Inverted channels near Juventae Chasma
Click for full image.

Cool image time! The photo to the right, cropped and enhanced to post here, attracted my immediate interest when I was going through the November image dump from Mars Reconnaissance Orbiter (MRO) because of its meandering sharp ridges, estimated to be about sixty feet high on average. While I have previously posted MRO images of inverted channels such as these, their particular sharpness, plus their large number in this localized single image, aroused my curiosity. What is their history? Does this illustrate an particularly interesting place on Mars?

The picture itself was taken was on September 29, 2020 by MRO’s high resolution camera. The blue areas in the color strip probably indicate coarser-grained surface. This makes sense, as these ridges are believed to have been initially carved as channels by flowing water or ice, which compressed their riverbed and thus made it resistant to erosion. Over time, the surrounding terrain eroded away, leaving that channel behind now as a upstanding ridge. The surrounding eroded terrain should thus be expected to be rougher.

Where did the water for these rivers come from, however? As always, the overview maps below give the context, and a possible explanation.
» Read more

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Chang’e-5 now in lunar orbit

8:31 am

The new colonial movement: China’s lunar sample return probe Chang’e-5 has now entered in lunar orbit, with its landing to occur in three days.

Over the next week, the probe, composed of four parts – the orbiter, lander, ascender and Earth re-entry module – will perform multiple complicated tasks on a tight schedule.

The four parts will separate into two pairs. The lander and ascender will head to the moon and collect samples, while the orbiter and Earth re-entry module will continue to fly around the moon and adjust to a designated orbit, getting ready for the docking with the ascender.

The landing operation is expected in three days. Once touched down on the lunar surface, the lander will collect two kilograms of lunar sample.

The plan once on the surface is to gather a sample from the surface as well as from a six-foot deep core sample.

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Wealthy environmentalist picks his preferred UK spaceport

11:27 am

Capitalism in space: A wealthy businessman who is also involved in environmental causes has invested almost 1.5 million pounds in the proposed spaceport planned for the Shetland Islands, the northernmost British islands.

What makes this investment especially interesting is this same environmentalist’s opposition to a different spaceport proposed for Sutherland, Scotland.

Danish businessman Mr Povlsen, who is reportedly worth £4.5bn thanks to his Bestseller clothes retail empire, and his wife own thousands of acres of land in Sutherland, and on other estates in the Highlands. [Their company] Wildland Ltd has raised concerns about Space Hub Sutherland’s impact on the Caithness and Sutherland Peatlands Special Protection Area, and has sought a judicial review of Highland Council’s permission for the satellite launch project.

Another of the Povlsens’ companies, Wildland Ventures Ltd, has invested in Shetland Space Centre.

This apparently is the ultimate in NIMBY (not in my backyard!). It seems this couple is throwing its weight behind the Shetland site in order to help keep the Sutherland site (in their backyard) from being built.

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Eroded and possibly wet Lohse Crater

2:51 pm

Gully flow near central peak of Lohse Crater on Mars
Click for full image.

Cool image time! Today we take a look at one particular 100-mile-wide crater, Lohse Crater, located in the southern cratered highlands on Mars. The photo to the right, cropped and reduced to post here, focuses in on one of the many eroding gullies found in the mountainous region surrounding the crater’s central peak. Taken on August 20, 2020 by the high resolution camera on Mars Reconnaissance Orbiter (MRO), the full image is centered on that central peak, just off the south edge of this cropped section. This new image is part of a long monitoring campaign, begun in 2007, of this central peak region. For more than six Martian years, scientists have been tracking the numerous gullies found throughout the central peak region to see if there have been any changes.

I focused on this specific gully because I think it illustrates well why planetary scientists are monitoring these gullies. Whatever flowed down from the cliff on the left hit the material on the right hard enough and fast enough to imprint a curve into the material on the crater floor. Moreover, it does not appear to have simply been a landslide, for several reasons. First, the cliff does not appear cut back at the flow’s head, as you would expect if a section had broken off. Second, the material in the flow does not look like debris from an avalanche. In fact, there does not appear to be very much debris in the gully at all.

Third, and most important, the flow appears to originate at the cliff base, kind of what you’d expect if there was seepage coming out of a layer in that cliff face. Kind of what you’d expect on Earth, at a spring!

Was that flow water? This is the big question. Lohse Crater is significant in that it was one of the first locations on Mars [pdf] spotted by Mars Global Surveyor in the late 1990s where gullies were found suggesting some form of regular erosion possibly caused by flowing water. As this 2005 paper then concluded,
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Next Virgin Orbit LauncherOne test flight set for late December

12:22 pm

Capitalism in space: According to Coast Guard notices, the next Virgin Orbit attempt to put its new LauncherOne rocket into orbit should occur sometime between December 18-21.

A Nov. 24 “Local Notice to Mariners” by the U.S. Coast Guard stated that Virgin Orbit “will conduct hazardous operations” offshore from San Nicolas Island, California, between Dec. 18 and 21. Those operations will take place during a four-hour window that opens at 1 p.m. Eastern.

The notice does not explicitly state that a launch will take place, but Virgin Orbit used the same language in a Coast Guard notice for its first orbital launch attempt in May. That earlier notice, which also cited “hazardous operations,” had the same four-hour window and location for the operations.

The company has not officially announced the launch date, but it has said it would fly this mission before the end of this year.

The article also notes that another smallsat launch startup, Astra, has announced its next launch attempt will take place during a 12-day launch window starting December 7th.

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Orbit of pristine comet in outer solar system is shifting inward

10:43 am

The orbit of a pristine comet that until now has kept it in the outer solar system, where it never got warm enough shed any material, is now shifting inward to join what is dubbed the Jupiter-family of comets, whose orbits are generally within that of Jupiter.

Although it has likely lost some supervolatile ices such as carbon dioxide ice (also known as dry ice) in the outer solar system beyond Jupiter, it is unlikely to have ever been in the inner solar system (where Earth, the other rocky planets, and [Jupiter-family comets] orbit), which is warm enough for water ice to sublime (‘evaporate’ from solid to gas),” Steckloff said. “This means that [Comet 2019] LD2 is a pristine comet, and presents a unique opportunity to observe how pristine [Jupiter-family comets] behave as their water ice begins to sublime for the first time and drive comet activity. Moreover, this transition is likely to finish in only 40 years from now, which is a blink of an eye for astronomy. This means that people alive today will be able to follow this object all the way through its transition into the [Jupiter-family] population.”

In 2019, when 2019 L2 was first identified, it was thought to be an asteroid that had suddenly become active, like a comet. Astronomers soon realized this was a mistake, that it was a comet whose orbit was being changed by its interaction with Jupiter.

The new data refines this conclusion, and confirms that observations of 2019 L2 will provide a lot of information about the make-up of the early solar system. More important, the comet’s orbit will allow for many observations, over a long period of time, unlike most comets that zip around the Sun in a year or so and then are gone.

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Problems discovered in new Japanese H3 rocket engine

10:07 am

Engineers at Mitsubishi have discovered technical problems in the engine for Japan’s new H3 rocket, forcing its first test launch to be delayed into 2021.

The Japanese space agency JAXA told SpaceNews that problems were found with the new LE-9 engine’s combustion chamber and turbopump. “Fatigue fracture surfaces were confirmed in the apertural area of the combustion chamber inner wall and the FTP blade of the turbo pump,” according to a JAXA spokesperson.

JAXA and Mitsubishi Heavy Industries (MHI), the prime contractor for the H3, were aiming to hold the inaugural launch by the end of 2020 before the discovery of issues in May. However engineers testing the LE-9 cryogenic liquid hydrogen and liquid oxygen engine for the H3 first stage encountered a potential issue back in May. This led JAXA to announce in September that the first flight would slip to some time in Japanese fiscal year 2021, beginning April 1, 2021. The rocket’s second launch likewise slipped to Japanese fiscal year 2022.

The H3 is intended as a cheaper and more competitive version of Mitsubishi’s H2 rocket, which has failed to garner much business outside of Japanese government launches because of its cost. That the H3 isn’t being built to be reusable however means it will likely not achieve that goal, as it will not be able to lower it enough to compete with SpaceX.

This launch delay further weakens its ability to compete, as it gives more time for other cheaper alternatives to hit the market.

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Russian company proposes new Russian space station post-ISS

9:27 am

Energia, the division in Roscosmos that manages the Russian manned program, including its share of ISS, has proposed that Russia build its own space station after 2025, and the reasons it gives strongly suggest they are worried about the condition of their 20-year-old and leaking Zvezda module.

The International Space Station’s systems are likely to keep breaking down after 2025, Energia company, which manages the Russian module, said and suggested building a national station instead. “Russia has commitments regarding the ISS through 2025. Several elements are already seriously damaged and about to stop functioning. Many of them are impossible to replace. After 2025, we expect many ISS elements to start breaking down en masse,” the deputy director-general of Energia, Vladimir Soloviev, said at a meeting of the Russian Academy of Sciences. [emphasis mine]

They don’t mention Zvezda by name, but the highlighted words point to it. Assuming the persistent leaks in the module are related to stress damage and age, this statement is recognizing publicly that replacing Zvezda is very difficult, or impossible, and that it is on the verge of complete failure.

Whether Russia has the money or resources to get another station built soon after 2025 is questionable, however. If they do decide to go it alone, I doubt they could launch a replacement before 2030, at the earliest, and likely much later than that.

If they do end the partnership with the U.S., it is unclear what happens to ISS. If the Russians choose to undock their portion of the station it will leave ISS somewhat crippled. It has been my impression that without all of the environmental systems in the Russian half, ISS cannot function. This might no longer be true, and will likely not be true with the planned arrival of Axiom’s private modules by the mid-20s. Timing however of all this remains critical.

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Giant wind eddies in the sands of Mars

12:13 pm

Wind eddies on Mars
Click for full image.

Cool image time! The image to the right, cropped and reduced to post here, was photographed by the high resolution camera on Mars Reconnaissance Orbiter (MRO) on August 5, 2020. It shows a cluster of the crescent-shaped gullies, apparently carved from desert sand by the prevailing winds.

Those prevailing winds here are from the southwest to the northeast. As the wind blows the sand to the east, it hits a more solid object, such as a mountain buried in the sand, which forces the wind and the blown sand to go around, much as water passes a boulder in river rapids. That solid object also causes an eddy to form at its face, the wind forced downward and then around and up, carving out the gullies by lifting the sand at the base of that solid object. The result are these crescent gullies, dubbed blow-outs.

The overview map helps explain why there is so much sand here, enough apparently to bury whole mountains.
» Read more

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Starship 50,000 ft hop now scheduled for Nov 30th

8:35 am

Capitalism in space: Having completed all preliminary static fire tests, SpaceX has now set November 30th as the target date for 50,000 foot high hop for its eighth Starship prototype.

SpaceX is understood to be conducting a Flight Readiness Review (FRR) for the test flight, with this final Static Fire test providing key data to the final go to proceed towards SN8’s big day.

Elon Musk has already calibrated public expectations on the expected outcome of SN8’s test, noting that “understanding exactly how the body flaps control pitch, yaw & roll during descent, such that the ship is positioned well to relight, flip & land, would be a big win.” As opposed to expecting SN8 to land feet first on the landing pad.

Musk’s point is important. The primary engineering goal for this first hop will be to find out whether they truly understand how to control and fly Starship. Their knowledge in this area is only computer based, and thus is very incomplete, and could very well be wrong, resulting in a failure that prevents a proper clean landing.

Such as failure however would actually be an engineering success, as it would give them the data needed to make later prototypes work. As for landing, they know how to do that already. Once they get the flying right, the landing should follow.

SpaceX has said it will live stream that hop. Should be a thrill to watch.

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SpaceX sets numerous launch records in placing 60 more Starlink satellites in orbit

10:23 pm

Falcon 9 booster landing for a record 7th time

Capitalism in space: SpaceX tonight broke a whole bunch of new launch records in launching another sixty Starlink satellites into orbit using its Falcon 9 rocket.

First, the leaders in the 2020 launch race:

31 China
22 SpaceX
12 Russia
5 ULA
5 Rocket Lab

The US now leads China 35 to 31 in the national rankings.

For SpaceX, this launch established the following landmarks for the company:
» Read more

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Rocket Lab declares first attempt at recovering a 1st stage a success

9:34 am

Capitalism in space: Rocket Lab has announced that the company’s first effort to recover a 1st stage of its Electron rocket during a November 19th launch was a complete success.

On Rocket Lab’s latest launch Nov. 19, the rocket’s first stage made a controlled reentry after stage separation, then released a drogue and a main parachute before splashing down about 400 kilometers downrange from its New Zealand launch site, where it was recovered by a boat.

The recovery itself went as planned. “The test was a complete success,” Peter Beck, chief executive of Rocket Lab, said in a call with reporters Nov. 23. “The stage splashed down completely intact. What it proved to us is that this is a feasible approach, and we’re really confident that we can make Electron a reusable launch vehicle from here.”

Eventually they plan to snatch the stage out of the air using a helicopter prior to hitting the water, but are presently focusing instead on developing the proper thermal protection and attitude control systems for the flight back to Earth. They are presently taking that first stage apart and analyzing what worked and didn’t work in protecting it during that flight.

According to Beck, they will do another splashdown recovery early in ’21 to refine things. They also hope to reuse some of the recovered components from both splashdown tests on later flights.

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Regulators coming after SpaceX’s Boca Chica facility and Starship

9:05 am

Capitalism in space? New FAA documents suggest that government regulators are not happy with the rapid and spectacular development by SpaceX of its Super Heavy/Starship rocket at Boca Chica, Texas, and are eager to impose restrictions and delays.

The issue revolves around revisions to SpaceX’s original FAA approval for its work at Boca Chica because the company has switched from flying Falcon 9 and Falcon Heavy rockets to developing and flying Starship and Super Heavy. While the FAA has been cooperative in issuing the necessary revisions, other agencies have raised red flags.

But the most important document of the bunch is the written reevaluation signed by the FAA on May 22. The file spans 26 pages, was required for SpaceX to receive its suborbital launch license from the FAA on May 28, and incorporates concerns from state and federal environmental agencies.

In the reevaluation, the Texas Parks and Wildlife Department and the US Fish and Wildlife Service took issue with several aspects of SpaceX’s plans and ongoing activities. Those criticisms targeted the “fluid nature” of the company’s construction projects, excessive road closures to Boca Chica Beach (which Brownsville locals prize), around-the-clock work that may affect nocturnal threatened or endangered species, prototype explosions, and sprawling wildfires the company has triggered.

The FAA responded to each concern in the document, ultimately determining “there are no significant environmental changes, and that all pertinent conditions and requirements of the prior approval have been met or will be met” with SpaceX’s suborbital test-flight plans.

However, SpaceX does not yet have the FAA’s go-ahead to launch any Starships to orbit from Boca Chica.

In its replies to concerns noted by other agencies — some of which call for a new EIS [environmental impact statement], which could take years to complete (an eternity in Musk time) — the agency repeatedly noted it is working with SpaceX to draft an “environmental review” of those plans.

Should Joe Biden and the power-hungry and controlling Democrats take control of the executive branch of the federal government, expect the FAA’s desire to help SpaceX to quickly end.

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Faulty valve on one Soyuz causes Russians to delay second Soyuz launch

8:44 am

Due to the discovery of a faulty valve on a Soyuz rocket being prepared for launch in French Guiana, Roscosmos has delayed today’s Soyuz rocket launch from Plesetsk, Russia, until December 3rd to allow engineers to inspect similar valves on that rocket.

This quote from Dmitry Rogozin, head of Roscosmos, from the first link, describing the problem, is somewhat amusing:

“The ‘faulty valve’ would be launched with the rocket, and it would return to Earth being just a heap of mishap metal, that would be the problem. There are always some flaws, but in our case, they cost too much. Happily, the low-quality detail was timely detected by the quality control system. However, in general, I do note a sharp decline in our suppliers’ responsibility and quality of their work,”

It appears the quality control problems with Russia’s aerospace industry are continuing. No one, including the Russians, should be surprised by this, as that industry has no competition to stimulate quality work and force bad companies out of business. Instead, everything is managed by Roscosmos from on top, with much of that management designed to eliminate competition entirely and protect the companies that presently exist..

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China successfully launches its Chang’e-5 lunar sample mission

2:45 pm

screen capture at Long March 5 launch of Chang'e-5
Screen capture from launch live feed

The new colonial movement: China today successfully used its Long March 5 rocket to launch its Chang’e-5 on the first lunar sample return mission since the 1970s.

If all goes well, the return capsule will return to Earth with its sample on December 15th.

China provided a live stream, in English, which I have embedded below the fold.

The leaders in the 2020 launch race:

31 China
21 SpaceX
12 Russia
5 ULA
5 Rocket Lab

The U.S. still leads China 34 to 31 in the national rankings.
» Read more

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Glacial eddies on Mars?

12:24 pm

Glacial eddies on Mars?
Click for full image.

Cool image time! The photo to the right, cropped and reduced to post here, was taken on August 15, 2020 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows a truly strange bunch of blocks beside a clean flow neatly organized in almost straight parallel lines.

What is going on? This location is at 38 degrees south latitude, a latitude where scientists have found a lot of features that resemble water ice glaciers, generally protected from sublimating away by a thin layer of dust and debris.

A first guess is that the smooth glacial flow at the lower right is disturbing the glacial material next to it, causing it to rip apart and break up. At the same time, the hollowed look of these glacial blocks suggests that the ice below that protective debris layer is also slowly sublimating away, causing the surface to sink.

The wider shot below helps confirm this impression.
» Read more

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SpaceX launches oceanography satellite

10:26 pm

Capitalism in space: SpaceX today successfully launched an oceanography satellite using its Falcon 9 rocket from the company’s California launch site at Vandenberg Air Force Base..

The first stage, making its first flight, successfully landed back on land near the launch site.

This was also SpaceX’s 21st successful launch in 2020, tying their record from 2018 for the most launches in a single year by a private company, ever. That record should be broken tomorrow, with their next Starlink launch.

The leaders in the 2020 launch race:

30 China
21 SpaceX
12 Russia
5 ULA
5 Rocket Lab

The U.S. now leads China 34 to 30 in the national rankings.

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Curiosity data suggests the occurrence of mega floods in Gale Crater

3:30 pm

The uncertainty of science: Using Curiosity data a team of scientists are now suggesting that some of the features the rover has seen were created during mega flood within Gale Crater, and this data also requires a rethinking of the present theories of the crater’s geological history.

This case includes the occurrence of giant wave-shaped features in sedimentary layers of Gale crater, often called “megaripples” or antidunes that are about 30-feet high and spaced about 450 feet apart, according to lead author Ezat Heydari, a professor of physics at Jackson State University.

The antidunes are indicative of flowing megafloods at the bottom of Mars’ Gale Crater about 4 billion years ago, which are identical to the features formed by melting ice on Earth about 2 million years ago, Heydari said.

The most likely cause of the Mars flooding was the melting of ice from heat generated by a large impact, which released carbon dioxide and methane from the planet’s frozen reservoirs. The water vapor and release of gases combined to produce a short period of warm and wet conditions on the red planet.

The press release above focuses on the catastrophic floods, but the research paper itself is really much more focused on the need to rethink present hypotheses for explaining the observed geology in Gale Crater. This report notes that they are finding patches of material that could not have been laid down as seen, based on those past theories, and proposes the catastrophic flood event as a possible solution.

In reading the paper however it is evident that even this new hypothesis is based on a limited amount of data, and thus can have holes punched in it as well. This is not to say that the paper is invalid, only that it must be taken with some skepticism. The data being obtained at Gale Crater simply incomplete. Curiosity is following only one path, and has not even left the foothills of Mount Sharp. In order to gain a wider and fuller understanding geologists need to study the entire crater floor, as well as the geology on the mountain.

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India’s first mission to Venus delayed a year

10:19 am

The new colonial movement: During a NASA planetary science conference on November 10th, an official of India’s space agency ISRO revealed that they have been forced to delay their first mission to Venus, dubbed Shukrayaan, till 2024.

T. Maria Antonita of the Indian Space Research Organisation (ISRO) detailed the status of the mission to scientists drafting a new 10-year plan for NASA’s planetary science program. Shukrayaan will be India’s first mission to Venus and will study the planet for more than four years.

ISRO was aiming for a mid-2023 launch when it released its call for instruments in 2018, but Antonita told members of the National Academies’ decadal survey planning committee last week that pandemic-related delays have pushed Shukrayaan’s target launch date to December 2024 with a mid-2026 backup date (optimal launch windows for reaching Venus occur roughly 19 months apart).

It appears they are using this extra time to consider a larger launch rocket, which would allow them to increase the orbiter’s capabilities.

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Despite permanent repair of crack, air still leaking from Zvezda

10:11 am

According to a Russian news report yesterday, air is still leaking from the Zvezda module of ISS, despite the permanent repair of the crack earlier this week.

Earlier, the crew locked the hatches into the intermediate chamber. The Mission Control asked whether the crew had measured the pressure before the hatch into that chamber was opened. The crew reported that the pressure went down considerably in the smaller part of the compartment while it remained isolated from the rest of the station by an airtight hatch. “The pressure in the intermediate chamber went down from 723 mm of the mercury column to 685 millimeters,” Ryzhikov said.

The report is poorly written, and is unclear on the exact date this air test was done. It is therefore possible the test was done prior to the permanent repair.

If however the air is still leaking, this suggests there might be more than one leak point in that part of Zvezda. According to this same story, the two Russian astronauts during their spacewalk on November 18th took pictures of the exterior area of Zvezda where the leak is located, and noted no exterior damage.

All these facts point to a very serious problem. If there was no exterior damage, it means the leak was probably not caused by a micrometeorite hit (though closer more extensive observations as well as a review of the photos might still conclude otherwise). The fact that the leak is continuing after the permanent repair suggests there is another leak, in the same part of Zvezda. That section is also a docking port, and would have experienced the most stress during the several dozen dockings that have occurred since Zvezda was launched in 2000.

These facts therefore suggest stress damage and aging as the cause, which means the problem will only get worse no matter what method is used to seal any future leaks.

One quick solution that would work, at least for awhile, would be to close the hatch on this intermediate chamber, and do no more dockings to it. This at least would seal the station from atmosphere loss, and reduce the stress on this section of Zvezda. Whether Progress freighters, which use this port, can use another port, or will have a more limited ability to dock, is not clear, however.

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Successful Rocket Lab launch and descent of 1st stage

10:26 pm

Capitalism in space: Rocket Lab today successfully used its Electron rocket to 30 smallsats into orbit from its launchpad in New Zealand.

They also did their first launch test of their planned method for recovering the first stage for reuse. In their case the first stage will use parachutes to slow its descent, and will then be grabbed by a helicopter to be brought back to land. On this launch they were only testing the parachute portion of this plan, and allowed the stage to land in the water, where they then recovered it.

The leaders in the 2020 launch race:

30 China
20 SpaceX
12 Russia
5 ULA
5 Rocket Lab

The U.S. now leads China 33 to 30 in the national rankings.

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Frost on a Martian hillside

3:02 pm

Frost on Martian hillside
Click for full image.

Cool image time! The image to the right, cropped to post here, was taken on August 27, 2020 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows a flat-topped mesa in an enclosed canyon dubbed Sisyphi Cavi in the high southern latitudes of Mars during the spring.

Notice the white spots in the gullies on the southern-facing slopes? From what I can gather from a bit of research, these indicate the presence of carbon dioxide frost. It was spring at this location when the photo was taken. At that time, the thin seasonal mantle of dry ice that covers Mars’ the polar regions south to 60 degrees latitude in the winter is sublimating away. This would explain why the frost is only present in the south-facing slopes. Since this is in the southern hemisphere, the south-facing slopes get much less sunlight, and would sublimate away later.

The photo was taken as part of a monitoring program to study this sublimation process. According to this abstract:

Superposition of channel features over and/or through the defrosting CO2 snowpack shows that the channels are active at the present day and probably have fluid flows every spring during the annual defrosting. In itself, this is a significant observation as active fluid flows of any nature have not yet been proven on Mars. However, the ambient temperature at the time of gully activity appears to require a role for CO2 in the formation of the channels, rather than water.

In other words, the coming and going of this dry ice frost each Martian year, in conjunction with the underground water ice also found here, appears to be causing erosion that then creates of the gullies themselves. More details from the abstract in this paper:
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