Author: Robert Zimmerman

Curiosity presently traveling over broken sandstone from an ancient dune field

10:27 am

Gator-back terrain on Mars
Click for full image.

According to a new paper, scientists now think that the rough and broken cap layer of the Greenheugh pediment that Curiosity is presently traveling across was originally a dune field periodically washed by water runoff, which with time eventually hardened into sandstone.

That broken terrain, dubbed “gator-back terrain” by the Curiosity science team, is shown clearly in the image to the right, taken on March 20, 2022. From the paper’s abstract:

The Greenheugh pediment is capped by a unit of broadly uniform thickness which represents the remains of the Stimson dune field that existed <2.5 Ga (mid- to late-Hesperian). ChemCam geochemical data shows that the sands deposited at the Greenheugh capping unit were sourced from a nearby olivine-rich unit. Surface waters then cemented the windblown sand deposits, ponding at the unconformity with the underlying mudstone unit, creating concretions towards the base. Episodes of groundwater circulation did not affect the rocks at Greenheugh as much as they did at other Stimson localities with the exception of acid-sulfate alteration that occurred along the unconformity. These results suggest that the ancient Stimson dune field was a dynamic environment, incorporating grains from the surrounding geological units on Mt Sharp. Furthermore, liquid water was stable at the surface in the Hesperian and was available for multiple diagenetic events along bedrock weaknesses.

In other words, material from Mount Sharp formed the dune fields, all of which were reshaped by groundwater circulation, with the dunes higher on the mountain seeing less groundwater.

The biggest uncertainty of these findings is explaining how surface liquid water could exist on Mars. Scientists have yet to develop an accepted model that would allow it. Another possibility would be the recent data that suggests Gale Crater was filled with glaciers. If so, scientists would need to figure out how the interaction of a Martian glacier might have geologically changed those dunes in a manner similar to groundwater.

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ISRO pinpoints cause of August ’21 failure of India’s GSLV

9:59 am

India’s space agency ISRO has completed its investigation of the failure of the third stage of its GSLV rocket during an August ’21 launch, identifying a leaky valve as the cause.

The leakage in the Vent and Relief Valve is being attributed to the damage in the soft seal that could have occurred during the valve operations or due to contamination and valve mounting stresses induced under cryogenic temperature conditions.

“The committee has submitted comprehensive recommendations to enhance the robustness of the Cryogenic Upper Stage for future GSLV missions, which includes an active LH2 tank pressurization system to be incorporated to ensure sufficient pressure in the LH2 tank at the appropriate time before engine start command, strengthening of Vent & Relief Valve and associated fluid circuits to avoid the possibility of leakage along with the automatic monitoring of additional cryogenic stage parameters for giving lift-off clearance,” Isro said.

India entire space industry almost completely shut down for two years due to its panic over the Wuhan flu. This launch was part of its effort to resume launches, and the failure only added to that shutdown.

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FAA again delays decision on environmental reassessment of SpaceX’s Boca Chica facility

1:32 pm

Surprise, surprise! According to an FAA email sent out today, the agency has once again, for the fifth time, delayed its decision on the environmental reassessment of SpaceX’s Boca Chica Starship launch site.

From the email:

The Federal Aviation Administration (FAA) is updating the release date for the SpaceX Starship/Super Heavy Final Programmatic Environmental Assessment (PEA) on the Federal Infrastructure Permitting Dashboard (Permitting Dashboard) and project website. The FAA plans to issue the Final PEA on April 29th. The planned April 29, 2022 release date will allow the FAA to review the Final PEA, including responses to comments, and complete consultation and coordination with agencies at the local, State, and Federal level. All consultations must be complete before the FAA can issue the Final PEA.

This date is now listed on the FAA’s SpaceX-Starship webpage. Nor is the decision a surprise. Expect the FAA to continue this charade month-to-month until after the November election, when the Biden administration will then feel free to block SpaceX’s effort in Boca Chica completely.

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Pushback: Lawsuit by teacher fired for his opinions to be heard by VA Supreme Court

11:49 am

Peter Vlaming, fired for his opinions
Peter Vlaming

Peter Vlaming was a successful French teacher in the West Point School District in Virgina in 2018, until he was fired for refusing to use male pronouns demanded by a female student.

In 2018, one of Peter’s female students decided to identify as male.

Peter went out of his way to accommodate this student. He said he would use the student’s preferred male-sounding name and avoid using pronouns.

But Peter simply could not use male pronouns for a female student because it would contradict his core beliefs. This was about more than just pronouns; it was about what pronouns mean. In speech, after all, pronouns identify us as either male or female.

Peter couldn’t in good conscience use male pronouns to identify a female student. At the same time, he made it clear that he wanted to work with the student by avoiding pronouns that may cause offense.

But that wasn’t good enough for the school district. It didn’t care about how Peter treated the student. It was on a crusade for conformity. It wanted to force Peter to speak words he disagreed with by using pronouns for the student—even when that student was not present. [emphasis in original]

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Ukraine War energizes commercial orbital remote sensing industry

10:31 am

Capitalism in space: It appears that the Ukraine War has had a positive effect on the emerging commercial remote-sensing satellite industry.

This industry is made up of a number of new private companies launching satellites to take high resolution images across a range of wavelengths, as well as do surveillance of communications. These companies have in the past decade slowly taken over this market from government satellites, which were becoming too expensive and launching too slowly to meet the military’s needs.

The war is illustrating their success, and firming up their businesses as other customers, such as news organizations, utilize their capabilities.

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Solar Orbiter takes closest image of Sun so far

10:18 am

Solar Orbiter's closest image of the Sun, so far
Click for full interactive image, where you can zoom in, a lot.

Cool image time! The European Space Agency (ESA) yesterday released several new images from its Solar Orbiter probe, taken when the spacecraft made its most recent closest approach of the Sun.

One of the images, taken by the Extreme Ultraviolet Imager (EUI) is the highest resolution image of the Sun’s full disc and outer atmosphere, the corona, ever taken.

Another image, taken by the Spectral Imaging of the Coronal Environment (SPICE) instrument represents the first full Sun image of its kind in 50 years, and by far the best one, taken at the Lyman-beta wavelength of ultraviolet light that is emitted by hydrogen gas.

The images were taken when Solar Orbiter was at a distance of roughly 75 million kilometres, half way between our world and its parent star. The high-resolution telescope of EUI takes pictures of such high spatial resolution that, at that close distance, a mosaic of 25 individual images is needed to cover the entire Sun. Taken one after the other, the full image was captured over a period of more than four hours because each tile takes about 10 minutes, including the time for the spacecraft to point from one segment to the next.

The photo to the right, reduced to post here, is the EUI photo.

Solar Orbiter has been in its science orbit since November, though that orbit over time will slowly be adjusted to swing the spacecraft into a higher inclination so that it can make the first close-up observations of the Sun’s polar regions. It is also working in tandem with the Parker Solar Probe, which observes the Sun from even closer distances using different instruments.

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Arianespace and SpaceX adjust to the new commercial launch market, without Russia

9:56 am

Link here. The article is mostly about how both companies need to adjust their launch schedules, with Arianespace scrambling to find rockets for its customers who had been scheduled to launch on Russian Soyuz-2 rockets and SpaceX describing how it will readjust its schedule with the addition of the OneWeb satellite launches.

The article had two quotes of interest. First, this fact about Arianespace’s new Vega-C rocket:

The Vega C uses an upper stage engine provided by Ukraine’s Yuzhmash, and supplies of that engine are in question because of the ongoing invasion. ESA officials said March 17 that they have three of those engines, enough to handle the anticipated Vega C missions this year.

ESA is supporting work on a new upper stage engine, M10, for a version of the Vega called Vega E that is slated to make its first launch around 2025. [Stéphane Israël, chief executive of Arianespace] said there was “no need” to accelerate work on Vega E, though, citing the Ukrainian engines in storage.

Thus, Vega-C is in the same boat as Northrop Grumman’s Antares, which also relies on Ukrainian rocket engines. When you also add the difficulty that both Blue Origin and ULA are having getting new rockets off the ground because of the delays in the BE-4 engine, it appears that in general there is presently a strong need across the entire rocket industry for rocket engines that is not being fulfilled by the engine builders available. This fact puts the new rocket engine company Ursa Major in a very strong position, should it begin to build bigger engines to serve this need. It also suggests there is an opportunity here for other engine builders, such as Aerojet Rocketdyne, if they have the wherewithal to grab it.

The second quote from the article of interest was from a SpaceX official, describing how the company is dealing with the sudden requirement to launch 216 OneWeb satellites:

Tom Ochinero, vice president of commercial sales at SpaceX, said at the conference that the company’s vertical integration and large fleet of reusable boosters offer the company flexibility to accommodate customers like OneWeb. “We can react very quickly because we’re just managing a fleet,” he said. [emphasis mine]

I just love the significance of the highlighted quote. Unlike all past rocket companies, SpaceX doesn’t have to build more rockets to add new customers, which makes adding new customers difficult and expensive. It simply can readjust how it uses the rockets in its fleet to get those new customers in orbit. And the new business will likely pay for SpaceX to expand that fleet so that it can launch more satellites even quicker.

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Ingenuity completes 23rd flight on Mars

11:05 pm

Overview map
Click for interactive map.

JPL announced tonight in a tweet that Ingenuity today completed its 23rd successful flight on Mars.

23 flights and counting! #MarsHelicopter successfully completed its 23rd excursion. It flew for 129.1 seconds over 358 meters [1,175 feet].

The overview map to the right was taken from the “Where is Perseverance?” webpage and annotated by me to show the planned future routes of both Perseverance and Ingenuity. The white dotted line shows Perseverance’s path, now having almost circled the rough ground on its way to the delta and Three Forks. The tan dotted line indicates Perseverance’s future route. The dashed pink and green lines indicate two possible future flight paths for Ingenuity.

The green dot marks the position the science team marked on the map for where Ingenuity landed after today’s flight. They have not yet calculated the actual flight path, which is why it is shown by the tan dashed line. This also means there is as yet some uncertainty about this landing spot.

Originally, the plan had been to get to this spot in one flight. For reasons not yet explained, when the helicopter took off on its 22nd flight during the March 19-20th weekend, it stopped after only about 100 feet. Today’s flight apparently completed the plan, putting the helicopter where it was supposed to be.

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The Ukraine War: Another week, little change

5:16 pm

The Ukraine War as of March 17, 2022
The Ukraine War as of March 17, 2022. Click for full map.

The Ukraine War as of March 24, 2022
The Ukraine War as of March 24, 2022. Click for full map.

Since my last post on the state of the Ukraine war one week ago, on March 17, very little has changed, with tiny gains and losses in territory by both sides.

The two maps to the right, the top from last week, the bottom from today, both created by the Institute for the Study of War (ISW) and simplified, annotated, reduced by me to post here, illustrate the somewhat static situation. The three green arrows in the bottom map point to the regions where the most significant changes have occurred. The red areas of regions under Russian control. The light red regions are areas the Russian claim control, but have not been confirmed. The blue dots and areas indicate Ukrainian advances or resistance.

For the Russians, the biggest territorial gains took place in the northeast, solidly linking two different fronts. The Russians also made minor gains near Chernihiv, northwest of Kiev, and near Donetsk.

Meanwhile, the Russians have still not taken the besieged city of Mariupol, though their forces have finally made some inroads into the city’s center.

For the Ukrainians, a Russian push beyond Mykolaiv in the south was completely defeated and forced to retreat. More importantly, Ukrainian forces have pushed the Russians back on the western outskirts of Kiev.

The primary question remains: Is this situation indicating that Russia is bogged down and facing a long protracted quagmire? Or does it more resemble the American situation shortly after D-Day, when Allied forces were stymied somewhat close to the beaches for almost two months before suddenly breaking out and overrunning much of France in the next two months.
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