Just Sittin' Around, Waitin' Around, For the Big Story

You know. Starliner's test tomorrow afternoon. There are some other stories around, but not much. 

Surprisingly, at least to me, the Federal Communications Commission, the agency that regulates and licenses radio, TV, and thousands of services that use them, is proposing new rules to cover the risk of debris-generating accidental explosions in space. To the best of my knowledge, radio isn't involved in any of that, so why is it their field to regulate? Sure satellites in space use radios, but so do taxis and I don't know of them regulating ways that keep taxis from getting into collisions.

The new rules would require applicants to assess and limit the probability of accidental explosions to less than one in a thousand for each satellite they submit for approval.

The probability metric is derived from NASA’s standard and would apply during and after the completion of mission operations.

Less than a 1 in 1000 probability of explosion? When we're looking at constellations with tens of thousands of satellites in them, doesn't that seem like too many explosions?

Oh, well. It doesn't have to make sense. Power grabbing expands exponentially. 

I read that JAXA was unable to contact SLIM (Smart Lander for Investigating Moon) as nightfall was approaching the lander, which has had a remarkable record of success in surviving the brutally cold lunar nights. Nobody really expected the lander to survive its first night on the moon after its January landing.

The Japanese Aerospace Exploration Agency (JAXA) attempted to send signals to SLIM on Friday and Saturday (May 24 and May 25), but was met with no response. A final attempt to reestablish contact was made on Monday evening (May 27) to no avail, marking a close to this month’s operations, the space agency announced on SLIM’s official X account.

SLIM, designed to demonstrate accurate lunar landing techniques, touched down on the moon’s surface on Jan. 20. Until now, JAXA has had successful monthly check-ins with the lander in February, March, and April — the probe managed to survive a shocking three frigid lunar nights. Usually, spacecraft can't even survive one of these two-week periods of cold isolation. Still, the space agency plans to try contacting SLIM again next month when the sun returns to the landing site, in hopes that the lander will reboot with sufficient solar power, the Japan Times reported.

Has the moon finally dealt the deathblow to SLIM? We'll have to wait about another two weeks until the sun rises again. 

An image JAXA released the first time SLIM woke up after a night on the moon back in January. For reasons known only to the mission planners, they've chosen to name the labeled rocks after dog breeds they estimate as being similar in size to that rock. 

How Lucky Can You Get?

When I first ran across this story a couple of days ago, the emphasis was that some space debris fell near a hiking trail in North Carolina and they thought it was from a SpaceX Dragon capsule. This left me confused for a little while because "everyone knows" that Dragons are reusable. The same handful of Cargo and Crew dragons have been flying for years, with refurbishment between missions. 

Then it occurred to me that both kind of Dragons (Crew and Cargo) also have the equivalent of the old Apollo era service modules, aptly renamed as a trunk. Could it be? 

Today, Space.com carried a story about the wreckage with several photos and lots of explanation.  The story was based on going to see the piece because the author lives close to where it came down; near Canton, NC — just outside of the city of Asheville, NC, where he lives.

The piece of debris at the head of the trail on which it was found. Image credit: Future/Brett Tingley

On May 22, groundskeeper Justin Clontz and his father were performing maintenance on a trail at the scenic Glamping Collective, a 160-acre luxury camping property offering private dome-style cabins on a mountaintop with panoramic views of the surrounding Pisgah and Cherokee National Forests. 

Coming around a bend in the trail that day, Clontz and his father stumbled upon an odd piece of junk lying on the ground, not far from the path at all. Roughly 3 feet by 3 feet (1 meter by 1 meter), the debris consisted of shredded carbon fiber composite and scorched metal, with exposed metal bolts and plates poking out of it. It had a faint smell, similar to ozone.

"It landed directly in the middle of the trail," Clontz told Space.com. "It was just wild. It was crazy-looking. I really didn't know what to think."

They go on to point out that there was no visible damage to trees or anything that they could identify. It was as if someone had carried the piece up to the trail and gently placed it there for everyone to see, but there were no obvious signs people had been there. 

At first they thought it might be from some military aircraft, but the lack of a crash site didn't support that. Astrophysicist Jonathon McDowell looked at the location, looked for some possible sources and didn't take long to conclude that it could well have come from the trunk module of the Crew Dragon that took the Crew 7 mission up and back down.  The actual Tweet allows you to see that map of the reentry path in better detail and it does look to be right over Canton, NC.

The Trunk (AKA Service Module) carries cargo or small satellites and is fitted with solar panels that supply power to Dragon when the vessel is in flight or docked to the ISS. It has fins for aerodynamic control during emergency aborts. While the Dragon itself has a heat shield across its bottom and is slowed to splashdown by parachutes, the trunk is jettisoned before the reentry really gets going, and burns up on reentry. Apparently not completely.

Why do I consider this lucky? Just finding it on the trail is incredibly lucky. Not getting hit by debris from a reentry is really quite the normal result. The surface area of the Earth is 197,000,000 square miles. Of that, the oceans, take up 139,600,000 sq. mi. or about 70% and, of course, stuff that falls into the overwhelming majority of the ocean is lost for good. The area that a person presents is "a couple" of square feet. To turn that 197 million square miles into square feet, multiply it by 27.828 million square feet in a square mile.  The piece of debris needs to hit a target of "a couple" of square feet in 5,492 trillion square feet.  The Aerospace Corporation has estimated the odds of being hit by a piece of space debris is less than a one in one trillion. I think it's quite a bit less than that.

The Glamping Collective plans to build a display case for the debris along the trail where it was found.

Starliner is "Go" For June 1

The flight readiness review for Saturday's launch of the Starliner Crewed Flight Test was held today as scheduled and mentioned in Saturday's summary. That source stated that if the review declared it was acceptable to launch, the Atlas V and Starliner stack will be rolled to the launch facility tomorrow. According to the statement published on NASA's Commercial Crew website:

NASA and Boeing teams polled “go” to proceed with plans to launch the agency’s Boeing Crew Flight Test to the International Space Station at 12:25 p.m. EDT Saturday, June 1. During a Delta-Agency Flight Test Readiness Review Wednesday at NASA’s Kennedy Space Center in Florida, leaders from NASA, Boeing, and ULA (United Launch Alliance) verified launch readiness, including all systems, facilities, and teams supporting the test flight.

A backup launch opportunity is available on Sunday, June 2, with additional launch windows on Wednesday, June 5, and Thursday, June 6.

Also as stated, astronauts Butch Wilmore and Suni Williams returned to the Kennedy Space Center yesterday. They will stay in quarantine at the Neil A. Armstrong Operations and Checkout (O&C) Building until Saturday’s launch. 

NASA leaders with Boeing and ULA partners, will hold a prelaunch news conference at 1 p.m. EDT Friday, May 31, at Kennedy’s press auditorium. 

NASA astronauts Butch Wilmore and Suni Williams arrive back at the Launch and Landing Facility at the agency’s Kennedy Space Center in Florida on Tuesday, May 28, 2024, ahead of NASA’s Boeing Crew Flight Test. Photo credit: NASA/Cory S. Huston

Like the previous crew demo flights, the Starliner will dock to the Space Station, and the two astronauts will spend about a week aboard before returning to Earth in the Starliner capsule. Unlike the Crew Dragon capsules, Starliner is designed to land in White Sands, New Mexico with a set of parachutes and an airbag for cushioning. While that's all the sources say, I'm assuming it's the White Sands Missile Range - it's where the previous Starliner Demo 1 and 2 missions landed.

Slow Day - So Only Two SpaceX Launches

I'm being slightly facetious; two launches in one day - even from opposite coasts of the US - isn't really slow, it's just not among the busiest days they've had.  Which is also to say that today's schedule was more than most other launch providers do in a month and more than some do in a year. 

The first launch of the day was this morning at around 10:24 AM ET from Cape Canaveral Space Force Station SLC-40. That was a launch of the Starlink 6-60 mission, 23 more satellites for the Starlink constellation. As luck would have it, I ended up being out of the house and missed it - by the time the sound from the launch gets here, the first stage has been dropped and it's hard to see anything. The booster for this mission was flying its 10th mission so we can't really call it a rookie, it's just nowhere near the fleet leader at 21 missions. Maybe the right word is that it's a Journeyman? (Remember when flying 10 times was unheard of?) The booster landed on A Shortfall of Gravitas in the Atlantic 8:15 after liftoff.

If you want to watch a video replay, SpaceX has it here. The coverage starts seven minutes before liftoff, so feel free to position the slider wherever you want it. 

The second mission of the day was for a paying customer, the European Space Agency, and is an Earth Observing Satellite called EarthCARE or the Earth Cloud Aerosol and Radiation Explorer. EarthCARE is a joint project of the ESA and the Japanese Aerospace Exploration Agency (or JAXA) and was launched from Vandenberg Space Force Base SLC-4E  at 6:20 PM ET. This booster was flying its seventh mission and returned to land beside the launch complex at 8:07 after liftoff. 

It's an interesting sounding mission to someone like this old radar designer, and the only difference between "light detection and ranging" and "radio detection and ranging" is the frequency they transmit and receive - which dramatically affects the things they can observe. From the ESA mission web page:

EarthCARE will employ high-performance lidar and radar technology that has never been flown in space before, with the objective to deliver unprecedented datasets to allow scientists to study the relationship of clouds, aerosols and radiation at accuracy levels that will significantly improve our understanding of these highly variable parameters.

There's a bit more succinct and easy to follow description at Space.com's coverage:

The mission will operate at an orbit similar in altitude to that of the ISS (250 miles, or 400 kilometers), but on a different plane: Instead of the more equatorial-focused ISS, EarthCARE will fly a sun-synchronous polar orbit that crosses the equator at local early afternoon, when sunlight is strongest in the region.

The mission will gaze down at particles of clouds and molecules of aerosols, or suspended particles in the atmosphere, to see how they interact with precipitation and how quickly they fall to our planet. EarthCARE will also "register the distribution of water droplets and ice crystals and how they are transported in clouds."

"This essential data will improve the accuracy of both cloud development models and their behavior, composition and interaction with aerosols, as well as improve future climate models and support numerical weather prediction," ESA officials added.

EarthCARE booster's landing at Vandenberg SFB. Screen capture from the SpaceX video of the launch. 

You may be aware that one of my main gripes about the climate catastrophists is how God-awful crappy their simulations are. "Wake me up when you can get clouds right" is my regular challenge. This looks like it could, potentially, get moving in that direction.

Same Old, Same Old

Holiday aside, it's a typical last week of May. It has been pretty much fully summer for a week or two, although our pattern of afternoon thunderstorms much of the week hasn't developed yet. A couple of days ago, the National Weather Service forecast site for central Florida posted warnings of heat indices to around 105 or more but it didn't seem to materialize. This afternoon, the nearby Melbourne airport said it was 93 with a "feels like" temperature of 102. I tend to dismiss those, thinking that's what 93 feels like here, but those warnings seem most appropriate for people visiting or spending their first summer here. 

Gee summer already? Only four months left to late September.

The same day as the heat warnings, the Weather Underground posted this UV warning. I want to direct your attention to the text at the bottom. I didn't select the skin type, that's the way it was displayed by default so I didn't think to see if it said something different for other colors.

This is the UV warning I generally refer to as "Fatal within 15 minutes" but it really says 18 minutes. No more than 8 to 18 minutes exposure to the sun? Is that total sun for a full day or 8 -18 minutes at a time? Doesn't seem like it could be the second one because then they should instruct us about how many 18 minute exposures we can get and how long we need to hide inside between them.

A regular part of my life since about the time I turned 17 has been inhalant allergies. I was in high school and I'm pretty sure I remember seeing my parents' doctor in the fall of my senior year.  He prescribed an antihistamine called Teldrin, which was good for 12 hours and helped me through the allergies, which tended to be all day things when the grass fields by our house or everglades were burning. By the time I was in my mid-20s and working for a living, I decided to see an allergist. 

If you've never gone through this exorbitant ritual, the "gold standard" treatment is they first find out what you're allergic to, and then desensitize you to it with a series of injections. The test is done by injecting a tiny amount of the allergen under your skin and judging your degree of sensitivity by how big of a welt you get. 

I'll never forget this. I was tested for 60 different allergens - 60 different pin prick shots - and I was allergic to all 60. On a scale of 1 to 4 ++, I only scored less less than 3 on two things: newsprint and "common skin bacteria." My usual summary is "I'm allergic to everything that is now, or once was, alive."

I'll cut the story short and not give thousands of details, but in the 53 years since I first saw that doctor when I was 17, I've had four allergists, had the 60 (or 120) injections test done at each of those doctors, had a nose surgery that one quack, um, doctor swore by and did nothing I could tell, I've been put on the latest, most modern, "non-drowsy" antihistamines that last 24 hours, more eye drops for (maddeningly itchy eyes), glucocorticoid nose sprays and every modern alternative.  

53 years later, I still get maddeningly itchy eyes, runny nose, sneezing and everything else. I've switched from prescription antihistamines - that have gone to being nonprescription - to an old four hour OTC drug called chlorpheniramine maleate, which happens to be the exact same drug as the Teldrin I was taking 53 years ago; it's just that Teldrin was designed to be slow release so it lasted 12 hours. Do I have allergy problems less often? I don't know how to know that. In the last week, I've taken the antihistamine tablets a few times, not continually, but I live in a different part of the state and I'm sure there are different plants and allergens here. 53 years of the state of the art care and taking exactly what I took at the start. The only progress is that it doesn't require a prescription and is a penny or two per pill.

Memorial Day 2024

These days I tend to wonder how many more of any holiday that our republic will survive to see, but this one is the hardest to come to grips with. Memorial Day is the day to honor those who fell fighting to preserve the republic and if Memorial Day falls, that's dishonoring every one of them. Every one of them gave themselves, their lives, their futures, for something bigger than themselves.

It's not just "the greatest generation" that saved the west in the all out war of WWII; it's all of them, from those we know of fighting in the first battles of the Revolution on April 19, 1775, (commemorated as Patriots' Day but some states shift the date to get a Monday Holiday) to those who were lost in Bumbling Biden's disastrous abandonment of Afghanistan, and those lost since then. We include losses from training accidents as well as actual enemy action.

For most people, Memorial Day is the semi-official Start of Summer, and it's a rare year indeed that it doesn't feel fully like summer by Memorial Day around here. The day tends to be marked by barbecues, trips out on the boat, or other outdoors activities. Let me join the chorus of folks saying that while you're enjoying your day, take a moment to remember or think of and thank those who gave their all in service to us. The ones who don't get to mark the holiday with us.

I say that in the belief that those who made that sacrifice wouldn't hold it against us to have a little fun on their day. 

Credit to Al Goodwyn at Creators Syndicate. 

Small Space News Story Roundup 37

Because it can be hard to find much on the weekend...

NASA and Boeing Find Deeper Problems with Starliner 

Not that they seem willing to put the launch off because of them. 

Senior managers have said they intend to launch Starliner's Crewed Flight Test on June 1 at 12:25 PM EDT, as noted in the addendum to Wednesday the 22nd's post. Since the first scrubbed attempt to launch Starliner, there has been weeks of detailed analysis of a helium leak and a "design vulnerability" with the ship's propulsion system. 

Extensive data reviews over the last two-and-a-half weeks settled on a likely cause of the leak, which officials described as small and stable. During these reviews, engineers also built confidence that even if the leak worsened, it would not add any unacceptable risk for the Starliner test flight to the International Space Station, officials said.

But engineers also found that an unlikely mix of technical failures in Starliner's propulsion system—representing 0.77 percent of all possible failure modes, according to Boeing's program manager—could prevent the spacecraft from conducting a deorbit burn at the end of the mission.

"As we studied the helium leak, we also looked across the rest of the propulsion system, just to make sure we didn't have any other things that we should be concerned about," said Steve Stich, manager of NASA's commercial crew program, which awarded a $4.2 billion contract to Boeing in 2014 for development of the Starliner spacecraft.

I love precision like "0.77% of all possible failure modes"! Such confidence! Such respect for significant digits! 

Question for any of you with lots of "probability and statistics" course work: how many trials would be needed to have high confidence it's more like 1% chance instead of a 5% chance? How many to determine it's more like 1% than a 10% chance? I assume that if it's really a 5 or 10% chance given some large number of trials, the failure would happen more often than if it was a 1% chance. How many to distinguish a 0.77% chance from a 1% chance? I'm betting on the order of tens thousands of trials. From a system that's going to fly maybe 10 times. Maybe.

I found the entire article unsettling but while I'm not a "belt and suspenders" guy, I'm not a test pilot either. There's a Robert A Heinlein quote (I think it was RAH) about test pilots; something like they'd jump off a building with rubber soles if you gave them odds of surviving it. 

Butch Wilmore and Suni Williams, still in pre-flight medical quarantine, will return to Florida on Tuesday to resume final launch preparations. NASA officials will call a flight test readiness review Wednesday, and if they give the green light, ULA will roll the Atlas V rocket and Starliner spacecraft back to the launch pad on Thursday, May 30. 

Starship FT-4 Set for Wednesday, June 5 at 8:00 AM EDT

In a Friday announcement, SpaceX has set a June 5 launch date for its next Starship integrated test flight, with a focus on demonstrating the ability to bring both stages of the vehicle back intact. The mission details seem like what we covered on Tuesday, 5/21. 

“The fourth flight test turns our focus from achieving orbit to demonstrating the ability to return and reuse Starship and Super Heavy,” the company stated. “The primary objectives will be executing a landing burn and soft splashdown in the Gulf of Mexico with the Super Heavy booster, and achieving a controlled entry of Starship.”

The company has made several upgrades to both the Super Heavy booster and the Starship itself, based on their failure analysis of Flight Test 3. 

SpaceX said that Starship “began losing the ability to control its attitude” several minutes after engine shutdown, while coasting on a suborbital trajectory. Video of the flight showed the vehicle slowly rolling. That loss of attitude control led to an automated decision not to perform a planned engine relight.

“The lack of attitude control resulted in an off-nominal entry, with the ship seeing much larger than anticipated heating on both protected and unprotected areas,” SpaceX stated, with telemetry lost at an altitude of 65 kilometers.

The company believes the attitude control issue was caused by the clogging of valves in thrusters used for roll control. SpaceX has added more thrusters for redundancy while upgrading thruster hardware “for improved resilience to blockage.”

The booster fired 13 of its 33 Raptor engines after separation for a boostback burn, but six of the engines began shutting down, triggering an early termination of the boostback burn. Only two of 13 engines ignited for the final landing burn.

The engine failures, SpaceX concluded, were caused by filter blockage in liquid oxygen lines, keeping propellant from reaching the engines. SpaceX experienced similar problems on previous Starship launches and made changes to the engine design to try to prevent it. “Super Heavy boosters for Flight 4 and beyond will get additional hardware inside oxygen tanks to further improve propellant filtration capabilities,” SpaceX said, along with unspecified “additional hardware and software changes” to improve the reliability of Raptor engine startup.

Another interesting little change they've made is to jettison the interstage adapter they added to allow igniting the upper stage before the booster separates.  They will still have that adapter in place but the way I read that, they'll drop the interstage adapter once the booster separates.

Booster 11 and ship 29, the Flight Test 4 hardware, stacked for the May 15 WDR. Screen capture from SpaceX video posted on X.

Voyager 1 Returning Science Data Again

NASA's Voyager office posted on Wednesday, May 22, that Voyager 1 has started returning science data from its few working instruments for the first time since its November computer memory failure that crippled the probe - the man-made object farthest from Earth in history. 

Voyager 1 has resumed returning science data from two of its four instruments for the first time since a computer issue arose with the spacecraft in November 2023. The mission’s science instrument teams are now determining steps to recalibrate the remaining two instruments, which will likely occur in the coming weeks. The achievement marks significant progress toward restoring the spacecraft to normal operations.
...
The plasma wave subsystem and magnetometer instrument are now returning usable science data. As part of the effort to restore Voyager 1 to normal operations, the mission is continuing work on the cosmic ray subsystem and low energy charged particle instrument. (Six additional instruments aboard Voyager 1 are either no longer working or were turned off after the probe’s flyby of Saturn.)

Regular readers will recall that back in November, Voyager suddenly started acting like something was seriously wrong. I likened it to the probe having had a stroke, although that's too anthropomorphic. The probe seemed to take commands and respond, it still kept its position and kept the data link back to Earth running, it's just that the replies it sent back were more like incoherent ramblings. It's as if Voyager had said its uncle had been eaten by cannibals before the mission started, only less coherent than that.

It took until March before Voyager successfully responded to a command to send back the contents of its memory and the programmers understood how to work around it. 

Launched in August and September of 1977 and coming up on their 47th year in space, it should be clear that the time the two Voyagers have left may not be as long as we might like. The next time a component dies, it may have more dire effects that preclude a fix like this, simply by having the spacecraft lose its ability to point its antenna back to Earth. 

As the first man-made objects to leave the solar system, as relics of America's early space program, and as testaments to how robust even decades-old technology can be, the Voyagers have carved out the kind of legacy usually reserved for remarkable things lost to time. There seems to a widespread interest in and affection for the two deep space probes. Voyager 2 isn't as far away because it spent more time investigating our solar system. 

Project engineers report that no one on the team was particularly excited or depressed about the failure, always believing they could repair it.

"We're confident that we can get back to business as usual soon, but we also know that we're dealing with an aging spacecraft that is bound to have trouble again in the future. That's just a fact of life on this mission, so not worth getting worked up about."

Full of Sound and Fury, Signifying Nothing

I don't think I've ever led with a quote from William Shakespeare, so there's a first time for everything. The quote, of course, is from Macbeth - Act 5 Scene 5 - and is one of the best known soliloquies in all of Shakespeare's plays. 

So why am I invoking this? What does this apply to? 

There was a congressional hearing today in which NASA Administrator Bill Nelson was confronted about the cost and schedule performance of the Artemis program and the hardware systems it depends on.  

At a May 23 hearing, Sen. Jeanne Shaheen (D-N.H.), chair of the Senate Appropriations Committee’s commerce, justice and science subcommittee, pressed Nelson on costs associated with Artemis and suggested that the agency convene an independent review of those costs.

She asked Nelson to describe “what NASA is doing to hold contractors accountable for cost overruns and scheduling delays” including whether the agency withheld payments to contractors for those overruns. She did not cite specific cases with Artemis but rather past studies on the overall costs of the program, including one estimate by NASA’s Office of Inspector General (OIG) that each of the first four Space Launch System/Orion launches will cost $4.2 billion.

Nelson argued that NASA docks the contractors bonuses if their performance doesn't meet objectives. He also pointed out their fixed price contracts, such as for the Human Landing System - a contract awarded to both SpaceX and Blue Origin. Sen. Shaheen responded by asking if NASA had considered an independent review board, citing the benefits of independent reviews on the James Webb Space Telescope program when it encountered additional overruns and delays late in its development.

Nelson responded that it was unnecessary. 

“We are constantly having other eyes” on Artemis, he said, citing reviews by OIG as well as the Government Accountability Office. “The fact is, when you go to the moon in order to go to Mars, it’s hard.”

NASA officials have, in fact, expressed some frustration with the level of outside scrutiny on Artemis. The agency’s response to the most recent OIG audit related to Artemis, regarding the agency’s readiness for the Artemis 2 mission, complained that OIG had not found any issues they were not already addressing and that working with the auditors caused “disruptions to ongoing workflow and priorities” for those working on the upcoming mission.

There's frustration with the progress of the Artemis program. Nothing they can do now will have any affect on the $4.2 billion per launch price tag of the missions. The costs are very likely to go up from that, but that cost goes back to the problems with getting SLS flyable. Until they resolve the Orion capsule's heat shield issues, there can be no real mission. The Artemis program is stalled. The big, slow-moving wheels of "big gubmint" have gummed up SpaceX's progress on getting Starship - the prototype of the Human Landing System - working properly.  

Artemis 2, the lunar flyby mission, is currently scheduled for September of 2025 and the first lunar landing mission is scheduled for September of 2026. I don't know that I'd take a bet that either one will go on time.

Senator Shaheen and NASA Administrator/former Senator Bill Nelson. Credit: NASA/Bill Ingalls

Nothing in this meeting will help the missions or help the whole Artemis program get back moving. "It is a tale told by an idiot, full of sound and fury, signifying nothing."

Starliner Crewed Test Flight Now Suspended "Indefinitely"

Word broke late Tuesday that Saturday's planned launch attempt for the Starliner Crewed Flight Test (CFT-1) has been cancelled with no word on a next date to attempt the flight. The issue is still the helium leak that they've been talking about since the first scrub during the countdown to a scheduled May 6 launch.  

The space agency did not describe what options are on the table, but sources said they range from flying the spacecraft "as is" with a thorough understanding of the leak and confidence it won't become more significant in flight, to removing the capsule from its Atlas V rocket and taking it back to a hangar for repairs.

Theoretically, the former option could permit a launch attempt as soon as next week. The latter alternative could delay the launch until at least late summer.

"The team has been in meetings for two consecutive days, assessing flight rationale, system performance, and redundancy," NASA said in a statement Tuesday night. "There is still forward work in these areas, and the next possible launch opportunity is still being discussed. NASA will share more details once we have a clearer path forward."

Astronauts Butch Wilmore and Suni Williams returned to their homes in Houston when the last reschedule was announced, so their visit will be extended for an unknown duration.

Of concern to me is that prior report said they had replaced the valve that was the initial concern and yet the problem is still there - implying the valve wasn't the only problem present or maybe even wasn't bad at all. 

ULA returned the Atlas V rocket to its hangar, where technicians swapped out the faulty valve in time for another launch attempt May 17. NASA and Boeing pushed the launch date back to May 21, then to May 25, as engineers assessed the helium leak. The Atlas V rocket and Starliner spacecraft remain inside ULA's Vertical Integration Facility to wait for the next launch opportunity.

Boeing engineers traced the leak to a flange on a single reaction control system thruster in one of four doghouse-shaped propulsion pods on the Starliner service module.

There are 28 of these reaction control system - or RCS - thrusters, small rocket engines on the capsule's service module. These thrusters are used for minor course corrections and control of the capsule's orientation. The service module also has dual sets of larger engines used for larger orbital adjustments. 

As has been mentioned before, a consideration in scheduling this mission has to be the ISS' schedule. Briefly, their best chances for this Starliner flight are before July, after which it gets a bit busier and harder to work with. Add to that concern is that ULA needs that launch pad for other missions, too. They plan to launch a US Space Force mission before the end of the summer; it will be the last mission to use an Atlas V rocket. They also plan to launch the second demonstration flight of their Vulcan Centaur rocket, most likely carrying Sierra Space's Dream Chaser, hopefully as soon as September.

The CFT-1 Starliner Capsule on top of its Atlas V ride at the SLC-41 launch pad. Image Credit: ULA on Flickr

 

EDIT 0740 AM EDT MAY 23 to add:  As of this morning, Next Spaceflight is showing the launch has been scheduled for next Saturday, June 1 at 12:25 PM EDT.

Starship Flight Test 4 Looks to be Within 2 Weeks

Two weeks according to Elon Musk. As usual, think of it as Elon Standard Time, but here's the full story.

"Starship Flight 4 in about 2 weeks," Musk posted on X, his social media platform, following a Starship countdown rehearsal Monday at the Starship launch site in South Texas. "Primary goal is getting through max reentry heating."

The article there on Ars Technica begins with the absolutely valid observation that the first three test flights have demonstrated that Starship can lift off the pad, stage properly, and can make it to orbit.  Now, it's time to prove that Starship can reenter and get back home. That will be the emphasis of Integrated Flight Test 4, or IFT-4. 

In case you missed it, on Monday, SpaceX at Starbase carried out a wet dress rehearsal of the Booster 11, Starship 29 stack, filling the nearly 400 foot tall rocket with 10 million pounds of super-cold methane and liquid oxygen. The WDR didn't culminate in a static firing, but covered everything up to the final steps before firing.

SpaceX then drained the cryogenic propellants from the rocket, and ground teams removed the Starship upper stage from the booster Tuesday for more work on the ship's heat shield. A few days before launch, SpaceX will install the rocket's self-destruct mechanism, which would be used to destroy the vehicle if it flies off course and threatens populated areas.

As always, the FAA must grant SpaceX a license to launch before they may. It's reported that they are still going over SpaceX's internal review of the IFT-3 mission back in March. The FAA considered that flight a mishap because the Starship lost control and disintegrated during reentry before it could make a targeted intact splashdown in the Indian Ocean. For SpaceX, the March flight was a resounding success. It was the first time a Starship test flight reached near orbital velocity, with full-duration burns by all 39 Raptor engines on the rocket's first and second stages.  

March's IFT-3 tested a few different things, such as performing a propellant transfer inside the Starship and opening the "Pez Dispenser" door that will be how Starlink satellites are deployed. (All indications continue to say that the propellant transfer worked properly). IFT-4 will focus on controlling the reentry of both the booster and Starship. Both the booster and ship of IFT-3 broke up during their descent.

SpaceX officials would like to see the Super Heavy booster for the next test flight, named Booster 11, make a controlled pinpoint splashdown in the Gulf of Mexico just offshore from Starbase. Halfway around the world, the Starship upper stage, known as Ship 29, will try to survive the blistering reentry back into Earth's atmosphere.

Starship is dressed in about 18,000 hexagonal heat-absorbing ceramic tiles to protect its stainless-steel structure during reentry, when temperatures peak at about 2,600° Fahrenheit (1,430° Celsius). In the final moments of the March test flight, onboard cameras captured spectacular video of the pinkish-orange glow of plasma flowing over the vehicle high over the Indian Ocean. This video was downlinked back to Earth through SpaceX's Starlink broadband network.

This rear-facing camera, mounted inside one of the forward flaps on Starship, shows plasma building up around the underside and rear flaps during reentry over the Indian Ocean.  Image credit: SpaceX 

Musk wants to see Starship survive the highest temperatures of reentry with all systems functioning. Remember, the ultimate goal here is a Return to Launch Site landing of the booster and rapid reuse. Musk has teased that SpaceX could try landing a Super Heavy booster back at the launch pad in Texas as soon as the next flight test. Since we're looking at maybe one week less than three months between the last IFT and this coming one, assume the same three months and the booster returning to Boca Chica to get caught by the chopsticks would be in September.

As Hurricane Season Gets Takes Its Position as “Next Up”

Here we are on the 20th of May and in Central Florida it's turning into full-on summer, while still a few months from turning into Crematoria. We're in the last couple of days of what may well have been the last cool front of the year, with highs that haven't actually gone over 90, and won't be close to that until the weekend. Hurricane season starts on June 1st. 

What's it going to be like?  

The big things to look at are sea surface temperatures, the El Niño Southern Oscillation (ENSO), and the overall weather. I'll take a little look at these and some of the predictions from the pros. Let me point out my standard disclaimer: I reserve the right to be wrong. I try not to be, but while I'm mostly just relaying other people's content, I might make some mistakes. Don't let my look affect your planning if you're in the parts of the US where hurricane preparation is part of your life. 

That said, let me start with sea surface temperatures, which were the big story last year. Back near the end of last July, I passed along a story that I'd read about the monstrous underwater volcano called Hunga Tonga-Hunga Ha'apai that erupted in January of '22.  Within a week of the eruption it was being noted as one of the most violent eruptions ever seen, with this startling statement from a group that monitors nuclear explosions. 

Titled “A nuclear-test monitor calls Tonga volcano blast 'biggest thing that we've ever seen',” it reports that an international group that monitors for likely atomic detonations has reported that at every one of their sites around the world - 53 of them - the infrasonic wave from the Tongan volcano is the largest thing they've ever measured, even bigger than the Soviet Union's Tsar Bomba, the biggest nuclear detonation in history. [BOLD added - SiG]

The point of that article was that the volcano (which I've come to call just Hunga-Tonga - which is probably like using the volcano's wrong pronoun) injected three times more water into the upper stratosphere than was originally estimated.  It injected 150-million metric tons or almost 40 Trillion gallons of water vapor into the atmosphere.  The concern expressed then was that water vapor is a potent greenhouse gas and it was going to affect the weather for years.  

Guess what. They were right in that last sentence. Not only were sea temperatures higher last year than any year going back to 1981, they're higher so far this year than last year. 

Something that worked in our favor (not just Florida, but the whole US) was that the ENSO switched to the El Niño phase, which tends to produce large scale winds that keep storms offshore and watching storms last year clearly showed a tendency to curve to the north farther out to sea than in La Niña years. The current ENSO state as shown on Watts Up With That looks like this:

Don't ask me to try to remember where it was most of last season, but I think it was in the yellow region around 1.0 to 1.5. It got higher than that, into the orange "strong" band, but never into the red "extremely strong" range. Right now, the forecast is for a 60% chance it will decline further into the La Niña range by June to August and an 85% chance it will be there for fall and early winter. August through September is the peak of hurricane season.

Both the temperatures and the La Niña state of the ENSO are indicators that we probably have a nasty hurricane season coming up. It's probably pointless to talk about Colorado State University forecasting 23 named storms with five category III or higher while University of Pennsylvania is forecasting 33 named storms. It's unusual to get more than one or two in a year and that's the ones you're going to care about. I tend to regard Weatherbell as worth following; they're an expensive subscription service that puts up a season forecast for free. They're calling for an active season as well and provide this map with the red area denoting the highest risks with "Accumulated Cyclone Energy" at 2 to 3 times the averages for a typical hurricane season. (ACE is basically wind strength times the number of hours at that speed)

They also predict 25-30 named storms, pretty much what CSU and UPenn are saying, of which 13-17 become hurricanes and 5-9 become Category III or higher. 

All of which says it seems like it's a nasty season coming. Since we're still 12 days away from the start of the season, some sort of tropical depression or storm isn't out of the question but the NHC says models don't show anything for the next seven days. We tend to see one form in May, typically in the Gulf of Mexico, every couple of years. If you're anywhere in the reddish area on that map, this is a good time to refresh your preps and check the status of things. "Two is one and one is none" and all that.  

Solar Cycle 25 Update for Mid-2024

While talking about the geomagnetic storms and some extrapolation about the solar cycle yesterday, it occurred to be that I hadn’t done one of my (semi-? fairly-?) regular update posts on Cycle 25 since mid-December, so six months between them seems like a good time to do another.  

Like the last time, Dr. Scott McIntosh of the National Center for Atmospheric Research, NCAR, gave a solar cycle 25 update on a radio group that I follow, about a month ago, and this is going to be based on what he talked about. I’m going to lead with NOAA Solar Cycle Progression chart from their web site as I often do. 

The gray band is the expected range of the sunspot number, the black trace showing a lot of peak to peak variation is the measured sunspot number, which has been higher than predicted for virtually all of the cycle. 

This horizontal scale is more spread out horizontally than the plot I used in December so that I could put a marker (red vertical line) at the last point for the monthly smoothed sunspot number (SSN) at the right end of the previous plot. You can easily see that the SSN hasn’t achieved the values from 2023. In the last month, we achieved the highest sunspot numbers since cycle 23, but two things apply here. First, this doesn’t include the month of May, and second, a monthly SSN isn’t necessarily moved by a couple of large daily numbers, it’s more like an average. We saw days with sunspot numbers into the 240s. 

Dr. McIntosh of NCAR is tremendously interested in the Smoothed number because it’s an indicator of the cycle’s strength. He rather famously predicted that cycle 25 would be much stronger than average, and rival some of the strongest ever. While his methods for predicting the end of one cycle and start of the next are new, he missed his prediction for the end of cycle 24 by about a year with the termination event showing up in December of 2021. That, in turn, lowered his predictions for cycle 25. While his predictions for the cycle match reality better than the majority of predictions before 25 really started, the cycle is turning out rather average.

This next graphic is kind of dense to look at – it combines two of Dr. McIntosh’s plots showing the previous cycles back to 1975 with his prediction from 2020 (in red) at the right end. Pasted to the right of that is the part of a duplicate plot that shows how it has actually developed. Note how the actual measured data is approaching the red, 2021 prediction and the green Mean Solar Cycle since 1750.

Finally, a plot I’ve shown regularly which shows the SSN for the last five cycles back to 1975. I like this plot because it’s my ham radio biography in one plot. I was first licensed in February 1976, so every cycle I’ve been through is on this plot (and I was a shortwave listener for the cycle before that). The plot is posted to Space Weather News, but is created by a separate site, Solen.info.

Which brings us to the big questions. So what happens next?  I’ll answer with one of my favorite quotes, this time from physicist Niels Bohr: "Prediction is very difficult. Especially if it's about the future." More seriously, will this cycle be a cycle with dual peaks like pretty much all of them on this plot have been? My guess is yes, it will be like the majority of these; mostly flat for a couple of years with a couple of peaks. Cycle 22 (black) appears to be flat for around 30 months or 2-1/2 years. Cycle 23 (red) has a more pronounced double hump but is above that dip between them for more like 40 months or 3-1/2 years. Cycle 24 (pink) the weakest cycle in 100 years held a Smoothed Sunspot Number above its dip between the peaks for close to 48 months. 

Dual peaks might be an indication of asymmetry between the northern and southern hemispheres on the sun; the dual peaks might become a stronger single peak if the two hemispheres had the most effective sunspots at the same time in close to the same numbers.

What Dr. McIntosh seems to be most interested in answering in that presentation is when cycle 26 begins and 25 ends.  His method of predicting the strength of the cycles depends on the start. He expects to see the first signs of cycle 26 starting before the end of this year.

Getting back to the dual peaks, cycle 23 was spitting CMEs and flares for a lot of time. The short green to olive drab curve between cycles 23 and 24 is this one, 25, and we’re not quite four years into what is generally thought of as an 11 year cycle. Put another way we’re 45 months into a roughly 132 month cycle. The past month got a lot of attention for the flares and CMEs that are more prevalent through the peak years and the first years of the decline to the cycle’s completion. It seems like an easy prediction to say we’ll be seeing more CMEs, solar flares and geomagnetic storms for the next four to five years.

Odds, Ends, Small Stories, and Miscellaneous

Blue Origin is set to return to its suborbital tourist flights Sunday morning, for the first flight since the aborted flight of September 12, 2022. Call it just about 3 months, one quarter of a year, short of two years since they've flown.

Historic flight ... This will be the 25th flight of Blue Origin's New Shepard rocket, and the seventh human spaceflight mission on New Shepard. Before Blue Origin's rocket failure in 2022, the company was reaching a flight cadence of about one launch every two months, on average. The flight rate has diminished since then. Sunday's flight is important not only because it marks the resumption of launches for Blue Origin's suborbital human spaceflight business, but also because its six-person crew includes an aviation pioneer. Ed Dwight, 90, almost became the first Black astronaut in 1963. Dwight, a retired Air Force captain, piloted military fighter jets and graduated test pilot school, following a familiar career track as many of the early astronauts. He was on a short list of astronaut candidates the Air Force provided NASA, but the space agency didn't include him. Dwight will become the oldest person to ever fly in space. 

This reference to Ed Dwight becoming the oldest person ever to fly to space comes from Ars Technica's weekly Rocket Report. I was taken aback because I recall that during William Shatner's flight, also on a Blue Origin New Shepard suborbital flight, in October of '21 that he was said to be the oldest person ever to fly into space. I thought he was older but the source says he was also 90. Do they compare ages to the day?  

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It's being said that last week's geomagnetic storm was among the 20 strongest on record (second story down).  The article opens with a photo of auroras taken from New Caledonia in the south Pacific, at a latitude of -26.4 degrees, by Frédéric Desmoulins, who photographed the display from Boulouparis in the island's south province. "I could see the red color of the auroras with my naked eye. According to the New Caledonian Astronomy Society, these photos are the first for this territory." 

The Auroras visible from New Caledonia by Frédéric Desmoulins 

"The auroral visibility from New Caledonia is really unique and extremely valuable," says Hisashi Hayakawa, a space weather researcher at Japan's Nagoya University. "As far as we know, the last time sky watchers saw auroras in the area was during the Carrington Event of Sept. 1859, when auroras were sighted from a ship in the Coral Sea."

Hayakawa specializes in historical studies of great auroral storms. He tries to go back in time as far as possible. The problem is, magnetometers and modern sensors didn't exist hundreds or thousands of years ago. Instead, he looks for records of aurora sightings in old newspapers, diaries, ships logs, even cuneiform tablets. Great Storms are identified by their low latitude--anything with naked-eye auroras below 30° MLAT (magnetic latitude).

"May 10th was definitely a Great Storm," declares Hayakawa. "Naked-eye auroras sightings in New Caledonia (MLAT = -26.4°) and Puerto Rico (MLAT = 27.2°) confirm this in both hemispheres."

The sunspot that produced that flare is on the far side of the sun now, but another magnetically complex sunspot group, AR3685, emitted an X3 flare on the 15th and a slightly weaker M7 flare yesterday (17th). The spot isn't really Earth facing, and NOAA is predicting a chance of minor geomagnetic storm "early on the 19th" - which it currently is in UTC as I write. If there has been an impact, it hasn't made news, yet. 

It's worth paying attention to because this spot is just starting it's transit across the Earth-facing hemisphere of the sun, meaning we have about two weeks for this one to fling more Coronal Mass at us. This happens at the cycle max every cycle and while the actual max may be hard to declare except in retrospect, we're close to the peak of this cycle (25). While 25 is stronger than the previous cycle 24, that one was the weakest in 100 years, and this one isn't as strong as cycle 23 - making it the second weakest in at least the last 50 years (visual plot of all those cycles here - bottom plot on that page). We can expect flares, CMEs and this sort of stuff from the sun for another two to three years.

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I've been slow in updating my blog reading list to link to Western Rifle Shooters' blog at Cold Fury. I thought that might end up being redirected from the old site I still linked to, but eventually concluded I should just link to it. A verbose way of saying WRSA's link in my right sidebar now takes you to the active web site.

Small Space News Story Roundup 36

SpaceX Stacks Flight Test 4 Starship 

On Wednesday, May 15, SpaceX Starbase stacked the next Flight Test; Starship 29 and Booster 11, on Boca Chica's Orbital Launch Mount and began testing the combination for Flight Test 4. 

Starship stacking is a dramatic and impressive sight. There's a striking juxtaposition of mechanical and natural beauty, for example, as a gleaming silver rocket rises amid shrub-studded seaside dunes. And that 400-foot-tall (122 meters) rocket is bigger and more powerful than any other launch vehicle humanity has ever built.

The stacking follows earlier testing performed separately with Flight 4's Super Heavy and Ship. SpaceX has already ignited the Raptor engines of both vehicles on the launch mount, in common and brief prelaunch trials known as static fires.

Time-lapse, 20 second long video on X here.

Screen capture from that SpaceX video. Image credit SpaceX. 

So Wen Launch? (as the 'net followers say) 

There's no date set and they still have to wait for a launch permit from the FAA. I've heard that will be after Memorial Day (Monday the 27th) before the FAA will grant the license meaning the launch could possibly be before June 1, but "3 to 5 weeks" (from now) is being widely quoted.  Just like it was being quoted around a month ago.

Starliner Slips Again

To reuse the headline from Tuesday, Starliner Slips Another Four Days. I guess the simple "helium leak" is either proving to be too much for the ground crews or the people that said it was a simple helium leak got something wrong. That four day delay was from the original scheduled launch date, today, May 17, to Tuesday the 21st. The latest bump moves it out to Saturday, May 25. As the position of their target, the ISS, moves across the sky the launch time moves earlier. The launch today was to have been 6:16 PM (Eastern - it's Cape Canaveral). Saturday's launch time will be 3:09 PM.

"The additional time allows teams to further assess a small helium leak in the Boeing Starliner spacecraft's service module traced to a flange on a single reaction control system thruster," agency officials wrote in an update today.

NASA also said:

Further analysis of the leak suggests that it's not a huge problem, but NASA, Boeing and ULA want more time to assess the situation, agency officials wrote in today's update.

Something about saying it's no big deal followed by "we want another four days to check that" strikes me as mixed messages. Maybe it's yet another sign of being a graybeard, but sometimes saying Use As Is can be the scariest thing they tell you. 

Joint Japanese-European Mercury Probe Having Troubles

On October 20, 2018, the European Space Agency (ESA) in partnership with the Japanese Aerospace Exploration Agency (JAXA) launched probe to investigate planet Mercury, the innermost planet of the solar system with several flybys culminating with going into orbit around the little planet for longer observations. The probe, called BepiColombo, launched atop an Ariane 5, now retired. 

It was reported today that the probe's thrusters have malfunctioned and the agencies aren't yet sure if it will be able to achieve orbit. 

The BepiColombo spacecraft ... could be feeling the heat even before it reaches its destination: Mercury. Thanks to a glitch, the spacecraft's thrusters are no longer operating at full power. The team has yet to determine how this will impact upcoming maneuvers, like a Mercury flyby set for later this year.

Destined to become just the second mission to orbit Mercury when in December 2025, BepiColombo is composed of two probes and something called the "Mercury Transfer Module" that scientists hope will answer many perplexing questions about the smallest planet in our solar system. (To be clear, BepiColombo has performed Mercury flybys before, but is yet to actually enter Mercury's orbit.)

The Mercury Transfer Module is intended to address questions like how a planet as blisteringly hot as Mercury could have ice in its polar craters. It implies the conduction of heat in the planet's surface is so low that thermal equilibrium favors heat radiating away from the planet over being conducted to the poles. Among other questions. 

The 48-million-mile-long (77-million-kilometer-long) journey to Mercury is far from straightforward for BepiColombo; the spacecraft will make a total of nine planetary flybys before being inserted into the relatively tiny planet's orbit. And, as ESA reports, the glitch experienced by the spacecraft on April 26 has complicated this journey further.

BepiColombo experienced the glitch as it was preparing for a maneuver to set it up for its fourth flyby of Mercury on Sept. 5, 2024. The problem centers on the Mercury Transfer Module, the leftmost module in this diagram.

The Mercury Transfer Module is equipped with solar arrays and an electric propulsion system used to generate thrust. As the spacecraft was about to begin its April 26 maneuver, however, operators found that the Transfer Module had failed to deliver enough electrical power to its thrusters.

As soon as the fault was identified, ESA operators set about rectifying it. By May 7, the team had restored power to the thrusters such that they reached 90% full capacity, but the power available from the Mercury Transfer Module is still below what it should be. This means BepiColombo is continuing to operate without its full thrust.

The ESA hasn't yet determined if the thrusters can still perform the job they're required to do, saying the BepiColombo team's main priorities are to keep the spacecraft's thrust stable at its current sub-optimal levels, and to work out how the spacecraft will handle upcoming maneuvers at less than full propulsion. The mission is scheduled to continue through 2028, or 10 years in space, with flybys set for Sept. 5 this year, with a fifth and sixth flyby set for Dec. 2, 2024, and Jan. 9, 2025. After that final flyby is when the spacecraft is to go into orbit around Mercury. If the thrusters can do that.

Intuitive Machines Improving Their Next Lunar Lander

The Intuitive Machines lander IM-1, Odysseus - quickly renamed Odie -  got a lot of attention and coverage here on the blog. It was, after all, the first US launched vehicle to land on the moon since the end of the Apollo program when it landed on February 22nd. Adding to the story was that the mission was seriously barfed up on the way to the moon but fixed in a story that would make TV's McGyver proud. Yes, the word "landing" only applied in the loosest sense of the word and the mission was a continuous string of "making do with what we got", but Intuitive Machines reported every paying customer was happy with their results. 

Facing that story, though, the company has started work on improvements to the next lander that will improve its chances of getting more right by the mission plans. IM-2 is set to be launched "later in the year."

In a May 14 earnings call, Steve Altemus, chief executive of Intuitive Machines, said the company will upgrade communications, tracking and landing systems based on the lessons from the company’s IM-1 mission in February, which landed but tipped over nearly on its side.

Those upgrades are based on an internal review of the performance of the IM-1 mission. “The review resulted in software and hardware advancements that we believe expand our technical capability to track our vehicle accurately in space and land with 20 times better precision on our next mission,” he said.

Other changes will include changing the placement of antennas on the lander to improve bandwidth and provide lower Bit Error Rate communications.

“The technical improvements for IM-2 are vertically integrated capabilities within the company that we can perform with little or no impact on our intended quarter 4 2024 launch date or require any additional capital investment while we continue assembly of the flight vehicle.”

There was also mention of “more robust test and verification processes” for IM-2. You might recall the story that during the final checkout before liftoff, the crew at the launch pad failed to disable a safety switch on a laser rangefinder on the lander before launch, and the followup verification procedures (most likely visual inspections) didn't identify that problem. That kept the laser from being used as intended during landing. Company executives said shortly after the landing that had the rangefinders been working, they believe they would have had a fully successful landing.

The company is also working on longer term missions, including an IM-3 lander scheduled for 2025 which will be anchored by NASA's Commercial Lunar Payload Services (CLPS) contract payloads, and a totally private sector mission after that. As well as others farther into the future.

In this screen capture from this video, you can see the leg on the left is broken and doesn't look like the one on the right.  In this photo, the engine is still firing and keeping Odie vertical.  Moments after the engine was cut, it tipped over, taking about two seconds to come to rest. 

SpaceNews spends some time and column space on Intuitive Machines' business picture and it certainly looks like their work on Odie was well received. The call they mention (quoted above) was a May 14, end of the quarter earnings call. They don't say if the company considers this their first quarter of the year (calendar year) or the second (fiscal year matching the Fed.gov fiscal year).

The company reported $73.1 million of revenue in the quarter, far higher than the $18.2 million in the same quarter a year ago. The majority of that revenue, more than $40 million, came from the company’s OMES III engineering services contract it has with NASA in the first full quarter of that contract, said Steve Vontur, acting chief financial officer.

Intuitive Machines had a net loss of $5.4 million in the quarter, an improvement on the $14 million loss in the first quarter of 2023. The company had a cash balance of $55.2 million as of the end of the quarter, which Vontur said would be sufficient for the company through the rest of the year. The company is forecasting revenues of between $200 million and $240 million for 2024.

Starliner Slips Another Four Days

The scheduled date for the Crewed Flight Test of Boeing's Starliner has slipped out again, due to Boeing troubleshooting a small helium leak in the Starliner spacecraft itself. The last date we had was this coming Friday, the 17th; that has now been rescheduled for Tuesday, May 21 at 4:43 pm EDT (2043 UTC).

Boeing's ground team traced the leak to a flange on a single reaction control system thruster on the spacecraft's service module.

There are 28 reaction control system thrusters—essentially small rocket engines—on the Starliner service module. In orbit, these thrusters are used for minor course corrections and pointing the spacecraft in the proper direction. The service module has two sets of more powerful engines for larger orbital adjustments and launch-abort maneuvers.

Like many other spacecraft, the thrusters are fueled by the toxic combination of hydrazine (N₂H₄) and nitrogen tetroxide (N₂O₄) using the helium just to pressurize the system. The leak is important because the Starliner is to stay docked at the ISS for the week of the CFT-1 mission and the pressure must be maintained. This is a common fuel/oxidizer system for small thrusters; the Crew Dragon currently docked to the ISS for the Crew 8 mission and the previous ones that have flown other missions have stayed docked for the months those missions stayed docked to the ISS.

According to NASA, engineers plan to address the helium leak using "spacecraft testing and operational solutions." In other words, managers don't anticipate any need to physically repair the leak.

The original cause of the launch scrub back on Monday, May 2nd, was due to a valve problem. ULA rolled the Atlas V back to their Vertical Integration Facility (VIF) to swap out the faulty pressure regulation valve on the Atlas V's Centaur upper stage. Once installed on the rocket, the new valve performed normally in tests inside the VIF. ULA will roll the rocket back to the launch pad before the next launch attempt; I think the last attempt at this mission rolled out two days before the launch date.

A view looking down onto the Starliner capsule atop its Atlas V launch vehicle inside the VIF at Cape Canaveral Space Force Station, Florida. Image credi: ULA

My first reaction to this picture was that I'd like to know what those two black streaks are, about 60 degrees apart on one side (top of the frame) and 120 degrees apart on the other side. They kinda look like burn marks. Then I thought maybe I don't really want to know that. "Ignorance is bliss" and all that.