Author: Robert Zimmerman

Flaky Martian rock

11:41 am

Flaky Martian rock
Click for full image.

Overview map
Click for interactive map.

Cool image time! The photo to the right, reduced and enhanced to post here, was taken on May 15, 2022 (sol 3474) by the high resolution camera on the Mars rover Curiosity, and shows a rock that was near the rover at that time that I estimate to be around three to four feet long.

This picture was taken the same day Curiosity also took a panorama and close-up images of a row of teeth-like boulders that sat a short distance in front of the rover. Those rocks, much larger than the one to the right, had numerous large flakes protruding from their sides.

This smaller rock has even more such flakes, all much smaller and clearly more delicate.

The overview map to the right shows Curiosity’s present position with the blue dot. The yellow dot marks where it was when it took this photograph. The red dotted line shows the rover’s original planned route. The white arrows indicate what the scientists have dubbed the “marker horizon,” a distinct layer found in many places on the flanks of Mount Sharp that they are very eager to study up close.

The green dot marks the approximate location of a recurring slope lineae, a place where the cliff is seasonally darkened by a streak that appears each spring and then fades.

The two orange dotted lines are my guesses for the two possible routes the rover will take from here to get back to its planned route, abandoned in mid-April when the Greenheugh Pediment was found too rough for Curiosity’s wheels. Though science team has not published a new route, the direction traveled in recent weeks suggests these are the possibilities. If I had to choose, I would favor the east route, as it bypasses more completely the pediment with its rough terrain.

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Did SpaceX’s Endeavour capsule have issues with its heat shield during its most recent return to Earth?

9:43 am

According to a May 23rd Space Explored article based on anonymous sources, the heat shield on SpaceX’s Endeavour capsule experienced “dangerously excessive wear upon reentry” because of a propellant leak.

Hypergolic propellant made its way into the Crew Dragon Endeavour’s heat shield, according to sources at SpaceX and NASA who spoke with Space Explored. This hypergolic propellant is used by the Crew Dragon in its Draco engines – hypergolic means that the two parts spontaneously combust upon contact. It is believed that this hypergolic propellant impacted the integrity of the heatshield, causing dangerously excessive wear upon reentry.

NASA however has now bluntly denied these claims:

“The data associated with Dragon’s recent crew reentries was normal — the system performed as designed without dispute. There has not been a hypergol leak during the return of a crewed Dragon mission nor any contamination with the heat shield causing excessive wear,” the NASA statement reads, in part.

“SpaceX and NASA perform a full engineering review of the heat shield’s thermal protection system following each return, including prior to the launch of the Crew-4 mission currently at the International Space Station,” the NASA statement continues. “The heat shield composite structure (structure below the tile) was re-flown per normal planning and refurbishment processes. The thermal protection system on the primary heat shield for Crew-4 was new, as it has been for all human spaceflight missions.”

Such a flat out denial by NASA strongly suggests that the anonymous sources relied on by Space Explored are not reliable, and got their facts wrong. While NASA will often try to hide or spin any issues to make them seem less worrisome, it has almost never denied the existence of a serious problem, when it was revealed that such a problem had occurred.

I know to say this sounds paranoid, but this story also suggests this claim might be part of the growing effort within the federal bureaucracy and the press to attack SpaceX, because of its new irrational hostility to Elon Musk because he supports achievement and free speech.

At the same time, SpaceX has recently had to discard and replace a Dragon heat shield planned for a future mission because of discovered “manufacturing defect” during normal preflight testing. This confirmed story, combined with the unconfirmed and questionable story above, suggests SpaceX needs to take a closer look at the Dragon heat shield design.

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Astroscale to deorbit OneWeb satellites, funded by the European Space Agency

9:23 am

Capitalism in space: Astroscale has obtained OneWeb as a major customer for its system to safely deorbit its defunct satellites, with the work partly funded by the European Space Agency (ESA). From the ESA press release:

There are currently two options for removing end-of-life OneWeb satellites from their orbits at the end of their predicted five to six years of service. Each has been allocated enough fuel to be able to actively deorbit at the end of its useful lifetime. But, in case of failure, each has also been built with either a magnetic or a grappling fixture [designed by Astroscale], so that a servicer spacecraft could collect and actively deorbit the satellite.

The servicer spacecraft that Astroscale will build and test is called “ELSA-M” and is planned for launch in 2024. The servicer spacecraft will be the first “space sweeper” capable of removing multiple defunct satellites from their orbits in a single mission.

Following this demonstration, Astroscale will offer a commercial service for clients that operate satellite constellations in low Earth orbit, providing the technology and capability to make in-orbit servicing part of routine satellite operations by 2030.

Apparently, the ESA will pay Astroscale a little less than $16 million to install its grappling fixture on OneWeb’s satellites as well as build and fly the test ELSA-M mission. Once that flight proves the technology by removing several satellites, OneWeb will be expected to pay for Astroscale’s services, as will any other satellite customers.

This deal gives Astroscale a significant leg up on any other junk removal companies, as it getting its grappling fixture in space on many satellites. If that fixture should become standard, it will allow Astroscale to become the dominate satellite junk removal company, at least for the near future.

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Engineers rethinking Ingenuity operations to keep it alive through the winter

9:07 am

The engineering team operating the Ingenuity helicopter on Mars have now determined that the cold oncoming winter temperatures on Mars are causing its systems to shut down during the night — at the edge of their designed temperature limits — and then reboot each morning, thus resetting its clock to the wrong time.

The result has been that the helicopter’s future is now definitely threatened. To address the cold winter temperatures and possibly keep Ingenuity alive, the engineers have come up with the following plan. First, they have focused on downloading from the helicopter all the remaining data still on-board, in case it shuts down permanently.

After all critical logs are transferred, the team will proceed with a recommissioning phase during which we will reestablish Ingenuity’s flight-readiness given our ongoing overnight cold-cycling. Like during the technology demonstration phase, we will perform a high-speed spin before proceeding to flight. Should Ingenuity receive a clean bill of health, we would be ready to execute a short sortie to the southwest in Flight 29. This flight will improve our radio link for approximately the next four to six months while Perseverance samples at the river delta.

In the meantime, the Ingenuity flight software team will be preparing a series of upgrades to enable advanced navigation features. These new capabilities will help Ingenuity ascend the river delta and continue its missions as a forward scout for Perseverance past winter.

All this effort will carry much greater risk, especially because Ingenuity is now operating far beyond its original planned capabilities, and the worst and coldest winter temperatures are yet to come. For the next three months or so the amount of sunlight available will be insufficient to power it as planned, and thus it will face a possibility of permanent failure almost every day. That 29th flight is thus likely critical to survival.

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First test flight of Momentus’s orbital tug has issues

8:49 am

Capitalism in space: According to a short press release from the company, tirst test flight of Momentus’s orbital tug — launched on a Falcon 9 on May 25th, has communications issues.

We have established two-way contact with the Vigoride Orbital Transfer Vehicle, and as is often the case with a new spacecraft, have had some initial anomalies. We are using an unplanned frequency as we work through this and are applying for a Special Temporary Authority (STA) with the FCC to address that in order to help command the vehicle back to nominal configuration. Our engineering and operations team is working to address the anomalies.

No further details have so far been released.

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SLS next dress rehearsal countdown scheduled for June 19th

8:44 am

NASA has now scheduled the next dress rehearsal countdown for its SLS rocket for around June 19th, with the rocket beginning its trip to the launch site on June 6th.

It appears the issues that prevented the completion of the dress rehearsal in April have all been addressed:

While inside the Vehicle Assembly Building (VAB), teams completed several major objectives, including assessing the liquid hydrogen system leak at the tail service mast umbilical, replacing the interim cryogenic propulsion stage (ICPS) gaseous helium system check valve and support hardware, and modifying the ICPS umbilical purge boots. The addition of hazardous gas detectors above the upper stage allows for additional visibility into any potential leaks during cryogenic operations.

Other than the rollout on June 6th, all future dates remain flexible, depending on what happens step-by-step.

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A high mountain inside Valles Marineris

6:12 pm

A high mountain inside Valles Marineris
Click for full image.

Cool image time! The photo to the right, cropped, reduced, and annotated to post here, was taken on January 4, 2022 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows the flat top of a mountain inside Candor Chasma, one of the side canyons of the solar system’s largest canyon, Valles Marineris.

The image was taken when the sun was about 32 degrees above the horizon, to the west, and thus apparently low enough to put the flat top mostly in shadow.

What is most spectacular about this photo is the sense of scale it portrays once you know the overall context. Note the many layered slope to the west. That slope will continue downward far beyond the left edge of this image, dropping for dozens of miles and about 13,000 feet. The overview map below makes this clearer.
» Read more

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Today’s blacklisted American: Teacher threatened with loss of license for expressing an opinion

1:17 pm

Marissa Darlingh: Her free speech not allowed in Wisconsin
Marissa Darlingh at the April 23rd rally: Her free speech forbidden by Wisconsin

They’re coming for you next: A Wisconsin teacher, Marissa Darlingh, has been threatened with loss of her teaching license by the Wisconsin Department of Public Instruction (DPI) for speaking publicly — on her own time and as a private citizen — at a feminist rally on April 23, 2022 against the modern queer movement to introduce perverse sex instruction into elementary schools.

During that rally, Ms. Darlingh publicly expressed that she “oppose[s] gender ideology” in elementary schools and that young children should not be “exposed to the harms of gender identity ideology” or given “unfettered access to hormones—wrong-sex hormones—and surgery.” She argued passionately that she “exist[s] in this world to serve children” and “to protect children,” and does not support social or medical transition of young children. In the passion of the moment, Ms. Darlingh at one point said “[expleteive] transgenderism,” referring to the “gender identity ideology” that she believes harms children.

The Wisconsin Department of Public Instruction (DPI) issued Ms. Darlingh a letter on April 29, informing her that the agency opened an investigation to determine whether to revoke her educator license for “immoral conduct” at the April rally. The letter cites Darlingh’s use of profane language as well as her statements “oppos[ing] gender identity ideology from entering [her] school building” and her statements that she “do[es] not believe children should have access to hormones or surgery” as examples of her “immoral conduct.”

You can view the DPI letter here [pdf]. In threatening to take away Darlingh’s right to teach, it also gave her the option to end the public investigation if she would simply “surrender her license.” To do so DPI kindly included an agreement for her to sign.

In other words, “You sure have a nice looking resume. It sure would be a shame if something happened to ruin it.”

Darlingh not only did not surrender her license, she enlisted legal help from the Wisconsin Institute for Law & Liberty (WILL), which immediately sent a letter to DPI [pdf] telling it to back off or face a lawsuit for violating Darlingh’s first amendment rights. The letter also took the offensive, closing with this demand:
» Read more

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Part 2 of Elon Musk’s most recent tour of Starbase

10:37 am

Looking up from the bottom of the tower
Looking up from the bottom of the tower

Looking down from the top of the tower
Looking down from the top of the tower

Tim Dodd of Everyday Astronaut has now posted part two of his long and most recent tour of Starbase at Boca Chica with Elon Musk. This section is 33 minutes long, and takes us to the top of the new orbital launch tower that SpaceX will use to launch Starship and Superheavy, as well as eventually catch Superheavy upon its return.

Part 1 can be viewed here.

The two images to the right are screen captures from today’s tour.

I have embedded Part 2 below. It has the following interesting take-aways:

  • Musk: “At SpaceX, we specialize in converting the impossible into late.”
  • Musk and his engineers spent several minutes describing in detail how the tower’s chopsticks will work in conjunction with Superheavy as it comes down and the chopsticks grab it.
  • Musk also provided some details about the Starlink-2 satellites, explaining that it is impractical to launch them on Falcon 9, and thus Starship must become operational to fly them.
  • The tour not only stopped near the top of the tower to get a close look at the attachment points for the chopsticks, it went to the tower’s top, at 469 feet in the air, 106 feet taller than the Saturn-5 rocket.
  • In discussing how the economy is not zero sum, Musk revealed why he is at heart a conservative, and is slowly finding this out. That he still leaves out that forgotten word that makes this all possible, freedom, shows his journey is not quite complete.
  • Musk also added his thoughts on the importance of making human civilization multi-planetary. For him, it is really a question of survival.

» Read more

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Spaceflight’s Sherpa-AC tug successfully deploys satellites

9:49 am

Sherpa-AC

Capitalism in space: Spaceflight’s first orbital tug, dubbed Sherpa-AC and launched on SpaceX’s May 25th smallsat Falcon 9 mission, has successfully deployed its satellites as planned.

Spaceflight successfully delivered all five customer payloads, including two hosted payloads on the Sherpa OTV [Orbital Transfer Vehicle, or tug], to their desired orbital destinations.

The Transporter 5 mission marks Spaceflight’s 51st launch, its sixth in 2022, and the first launch of the Sherpa-AC OTV model. Sherpa-AC, named for its “Attitude Control” capabilities, augments Spaceflight’s base free-flying Sherpa with key functionality including a flight computer, attitude knowledge and control, and more, making it ideal for servicing hosted payloads on orbit.

Organizations on Spaceflight’s Transporter 5 mission include Xona Space’s Huginn mission, NearSpace Launch Inc.’s TROOP-3, MIT Lincoln Laboratory’s Agile Micro Sat, and Missile Defense Agency’s CNCE Block 2.

The picture above, reduced to post here, shows Sherpa-AC as launched. According to Spaceflight’s webpage, Sherpa-AC can act either as the service module for a smallsat, providing power, attitude control, and communications, or as a tug, bringing the cubesat to its desired orbit and then deploying it. On this flight three cubesats were deployed, and two remain attached, using Sherpa-AC as their service module.

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