Artemis Moon Program

[TomcatViP]

Meanwhile, NASA wants to make sure you don't get cold feet with Artemis:

Just what you need for the holidays... the coziness of a crackling and roaring rocket engine! Technically, this fireplace packs the heat of the SLS rocket’s four RS-25 engines and a pair of solid rocket boosters – just enough to get you to the Moon! (And get through the holidays with your in-laws.)

View: https://youtu.be/_cgTVTwu4nw

 

[NMaude]

Phillip Sloss has a new video out about possible Artemis updates for this month:

In this video I'll take a look at what could be ahead in the final month of 2024, now that Thanksgiving week is ending. At the Kennedy Space Center, the rest of Artemis II stacking waits for a possible December decision on the Orion heatshield, and preparations are being made to stand up the Artemis II SLS Core Stage for some offline work in the meantime.

I'll also go over the two SLS elements that were stacked, an Artemis II flight crew KSC visit before Thanksgiving, and a few other news and notes.

With possible decisions before the end of the year and possible announcements around the change in administrations, there's time to take a look at watch items for Artemis II, III, and the big picture for Artemis on a relatively slow news week.

Imagery is courtesy of NASA, except where noted.

00:00 Intro
00:40 Artemis II SLS booster aft assembly stacking recap
04:06 Artemis II flight crew visit to KSC
05:15 VAB High Bay 2 notes, preparing to host Artemis II SLS Core Stage
06:03 Other news and notes, HLS Cargo awards and an Orion heatshield delivery
08:27 Big picture outlook as 2024 ends
12:54 Thanks for watching!

Personally I hope that the decision to go ahead with the stacking of Artemis II goes ahead this month.

 

[publiusr]

View: https://youtu.be/_cgTVTwu4nw

Arty dreams roasting on an open fire...DOGE shears nipping at your nose...

Sadly, I wonder if this stacking is just a way to delay the inevitable by looking busy.

"Aw, Mom---we were about finished with the snowman."

That heartwarming hearth scene makes me want a hot toddy....with fentanyl....I keep hearing the Attestupa theme from MIDSOMMAR--tell Mike Griffin to come down from Bechtel 's LUT...oh, where was I...ah yes, SLS must be an Ari Aster production--nothing left except head trauma and the wailing.

 

[NMaude]

Phillip Sloss has a video out concerning the Orion heat-shield and what NASA decides will effect when Artemis II stacking starts:

We don't know for certain when, but NASA's Orion base heatshield investigation is expected to culminate in a set of decisions by the end of 2024, and this video takes a look at what is known ahead of that announcement. The Avcoat thermal protection material ablated away in larger pieces than predicted during the Artemis I re-entry back to Earth from the Moon two years ago.

After almost two years, NASA recently said it now understands what happened, but hasn't explained that publicly or said how it is going to resolve the issue with the next two heatshields that were already built. In this video I'll recap what has been said by NASA or by watchdog groups and what decisions are anticipated in the last few weeks of the year.

Imagery is courtesy of NASA, except where noted.

00:00 Intro
01:02 Orion heatshield design history
02:52 Artemis I lunar skip re-entry
07:00 Description of heatshield performance and issue(s) from Artemis I
11:00 History of the heatshield investigation so far
17:56 Where are we now?
21:15 How lunar re-entry trajectories could influence launch availability
24:25 Looking at upcoming heatshield decisions
26:40 Thanks for watching!

 

[Flyaway]

https://twitter.com/x/status/1864735562432659605

View: https://twitter.com/SpaceflightNow/status/1864735562432659605


That's a minimum of 3.4 years between Artemis 1 and 2 launches.

https://twitter.com/x/status/1864737687241920733

View: https://twitter.com/NASAWatch/status/1864737687241920733


NASA Identifies Cause of Artemis I Orion Heat Shield Char Loss

After extensive analysis and testing, NASA has identified the technical cause of unexpected char loss across the Artemis I Orion spacecraft’s heat shield.

Engineers determined as Orion was returning from its uncrewed mission around the Moon, gases generated inside the heat shield’s ablative outer material called Avcoat were not able to vent and dissipate as expected. This allowed pressure to build up and cracking to occur, causing some charred material to break off in several locations.

“Our early Artemis flights are a test campaign, and the Artemis I test flight gave us an opportunity to check out our systems in the deep space environment before adding crew on future missions,” said Amit Kshatriya, deputy associate administrator, Moon to Mars Program Office, NASA Headquarters in Washington. “The heat shield investigation helped ensure we fully understand the cause and nature of the issue, as well as the risk we are asking our crews to take when they venture to the Moon.”

Findings

Teams took a methodical approach to understanding and identifying the root cause of the char loss issue, including detailed sampling of the Artemis I heat shield, review of imagery and data from sensors on the spacecraft, and comprehensive ground testing and analysis.

During Artemis I, engineers used the skip guidance entry technique to return Orion to Earth. This technique provides more flexibility by extending the range Orion can fly after the point of reentry to a landing spot in the Pacific Ocean. Using this maneuver, Orion dipped into the upper part of Earth’s atmosphere and used atmospheric drag to slow down. Orion then used the aerodynamic lift of the capsule to skip back out of the atmosphere, then reenter for final descent under parachutes to splashdown.

Using Avcoat material response data from Artemis I, the investigation team was able to replicate the Artemis I entry trajectory environment — a key part of understanding the cause of the issue — inside the arc jet facilities at NASA’s Ames Research Center in California. They observed that during the period between dips into the atmosphere, heating rates decreased, and thermal energy accumulated inside the heat shield’s Avcoat material. This led to the accumulation of gases that are part of the expected ablation process. Because the Avcoat did not have “permeability,” internal pressure built up, and led to cracking and uneven shedding of the outer layer.

Teams performed extensive ground testing to replicate the skip phenomenon before Artemis I. However, they tested at much higher heating rates than the spacecraft experienced in flight. The high heating rates tested on the ground allowed the permeable char to form and ablate as expected, releasing the gas pressure. The less severe heating seen during the actual Artemis I reentry slowed down the process of char formation, while still creating gases in the char layer. Gas pressure built up to the point of cracking the Avcoat and releasing parts of the charred layer. Recent enhancements to the arc jet facility have enabled a more accurate reproduction of the Artemis I measured flight environments, so that this cracking behavior could be demonstrated in ground testing.

While Artemis I was uncrewed, flight data showed that had crew been aboard, they would have been safe. The temperature data from the crew module systems inside the cabin were also well within limits and holding steady in the mid-70s Fahrenheit. Thermal performance of the heat shield exceeded expectations.

Engineers understand both the material phenomenon and the environment the materials interact with during entry. By changing the material or the environment, they can predict how the spacecraft will respond. NASA teams unanimously agreed the agency can develop acceptable flight rationale that will keep crew safe using the current Artemis II heat shield with operational changes to entry.

NASA’s Investigation Process

Soon after NASA engineers discovered the condition on the Artemis I heat shield, the agency began an extensive investigation process, which included a multi-disciplinary team of experts in thermal protection systems, aerothermodynamics, thermal testing and analysis, stress analysis, material test and analysis, and many other related technical areas. NASA’s Engineering and Safety Center was also engaged to provide technical expertise including nondestructive evaluation, thermal and structural analysis, fault tree analysis, and other testing support.

“We took our heat shield investigation process extremely seriously with crew safety as the driving force behind the investigation,” said Howard Hu, manager, Orion Program, NASA’s Johnson Space Center in Houston. “The process was extensive. We gave the team the time needed to investigate every possible cause, and they worked tirelessly to ensure we understood the phenomenon and the necessary steps to mitigate this issue for future missions.”

The Artemis I heat shield was heavily instrumented for flight with pressure sensors, strain gauges, and thermocouples at varying ablative material depths. Data from these instruments augmented analysis of physical samples, allowing the team to validate computer models, create environmental reconstructions, provide internal temperature profiles, and give insight into the timing of the char loss.

Approximately 200 Avcoat samples were removed from the Artemis I heat shield at NASA’s Marshall Space Flight Center in Alabama for analysis and inspection. The team performed non-destructive evaluation to “see” inside the heat shield.

One of the most important findings from examining these samples was that local areas of permeable Avcoat, which had been identified prior to the flight, did not experience cracking or char loss. Since these areas were permeable at the start of the entry, the gases produced by ablation were able to adequately vent, eliminating the pressure build up, cracking, and char loss.

Engineers performed eight separate post-flight thermal test campaigns to support the root cause analysis, completing 121 individual tests. These tests took place in facilities with unique capabilities across the country, including the Aerodynamic Heating Facility at the Arc-Jet Complex at Ames to test convective heating profiles with various test gases; the Laser Hardened Materials Evaluation Laboratory at Wright‐Patterson Air Force Base in Ohio to test radiative heating profiles and provide real-time radiography; as well as the Interaction Heating Facility at Ames to test combined convective and radiative heating profiles in the air at full-block scale.

Aerothermal experts also completed two hypersonic wind tunnel test campaigns at NASA’s Langley Research Center in Virginia and CUBRC aerodynamic test facilities in Buffalo, New York, to test a variety of char loss configurations and enhance and validate analytical models. Permeability testing was also performed at Kratos in Alabama, the University of Kentucky, and Ames to help further characterize the Avcoat’s elemental volume and porosity. The Advanced Light Source test facility, a U.S. Department of Energy scientific user facility at Lawrence Berkeley National Laboratory, was also used by engineers to examine the heating behavior of the Avcoat at a microstructure level.

In the spring of 2024, NASA stood up an independent review team to conduct an extensive review of the agency’s investigation process, findings, and results. The independent review was led by Paul Hill, a former NASA leader who served as the lead space shuttle flight director for Return to Flight after the Columbia accident, led NASA’s Mission Operations Directorate, and is a current member of the agency’s Aerospace Safety Advisory Panel. The review occurred over a three-month period to assess the heat shield’s post-flight condition, entry environment data, ablator thermal response, and NASA’s investigation progress. The review team agreed with NASA’s findings on the technical cause of the physical behavior of the heat shield.

Heat Shield Advancements

Knowing that permeability of Avcoat is a key parameter to avoid or minimize char loss, NASA has the right information to assure crew safety and improve performance of future Artemis heat shields. Throughout its history, NASA has learned from each of its flights and incorporated improvements into hardware and operations. The data gathered throughout the Artemis I test flight has provided engineers with invaluable information to inform future designs and refinements. Lunar return flight performance data and a robust ground test qualification program improved after the Artemis I flight experience are supporting production enhancements for Orion’s heat shield. Future heat shields for Orion’s return from Artemis lunar landing missions are being produced to achieve uniformity and consistent permeability. The qualification program is currently being completed along with the production of more permeable Avcoat blocks at NASA’s Michoud Assembly Facility in New Orleans.

 

[publiusr]

If there are massive cuts to NASA, Mr. NASAWATCH will be just as guilty as Trump--all he has ever done is undermine NASA to the point where massive cuts look to be inevitable.

But he hates MSFC more than Elon...on his head be it.

If NASA is gutted... don't get mad at Elon, Jared, or the Donald. "If someone behaved predictably and you get angry, who's crazy?"

No, if this all goes south, it will on Keith Cowing's head who invited all this schism to begin with all his negativity.

Maybe someone can explain it to him.

Years ago, Jim Hillhouse at AMERICA SPACE tried to warn everyone that OldSpace and NewSpace needed to praise each other.

He was right.

 

[NMaude]

If the Artemis II mission is going to be flown with an unmodified heat-shield but with a modified reentry profile then why the six-month delay, this does not make sense and it plays into the hands of the programme's critics.

 

[alberchico]

If Trump wants to put boots on the Moon by the end of his term then he'll have no choice but to stick with SLS and go full speed ahead with the plans currently in place. Also many politicians who support Trump will push back if their own interests are threatened. I would argue that with all the jobs that the SLS program creates across many districts, it is politically cancel proof. The only thing that could cause the SLS to be scrapped would be a catastrophic failure attributed to some kind of design flaw.

 

[publiusr]

It looks that way—we’ve been flooded with images of Orions TPS that folks forget about Starship’s own tile issues.

 

[NMaude]

Phillip Sloss has uploaded a video about the informal nomination of Jared Isaacman to head NASA and how it may effect the SLS and Artemis programmes:

NASA's Orion heatshield investigation concluded on December 5th, and the space agency announced in a press conference that they accepted the recommendation to fly the Artemis II Orion heatshield as-is. The launch was pushed back to April 2026 for other reasons and Artemis III was delayed until mid-2027; however, President Trump nominated Jared Isaacman to be the next NASA Administrator, which continues the narrative that an Artemis shake-up could be coming in January.

There were a lot of details in the press conference about the status of Artemis II preparations and planning for the next milestones stacking the SLS vehicle for that, but not so much on Artemis III, which depends on not just Orion and SLS, but also Starship HLS and Axiom Space lunar surface spacesuits. The commercial providers are developing private products with proprietary technology, so NASA leadership can't speak for them. The outlook for the public and private programs participating in Artemis III will remain a storyline for future videos.

That is, if the plans for Artemis II and III are continued next year. There are a few takeaways in this video from the early nomination, and the obvious implication of orphaning Orion if SLS is cancelled by Isaacman and Elon Musk next year. Orion is still a unique, crew-rated spacecraft, so sticking it on top of another launch vehicle won't be as easy or as inexpensive as it is to do virtually or hypothetically. In this video, I'll take a first look at the cost and schedule questions and implications of a theoretical Orion launch vehicle move.

Imagery is courtesy of NASA, except where noted.

00:00 Intro
00:34 Overview of findings from the completed Orion base heatshield investigation
03:03 Initial thoughts, takeaways from the December 5 Artemis press conference
13:38 Jared Isaacman is the new NASA Administrator nominee
15:03 The devil is in the details about a new launch vehicle for Orion
19:51 A post-heatshield decision look at the big picture
23:26 Thanks for watching!

 

[NMaude]

New update on the status of Artemis-II and considerations for new Orion LV:

There's more to cover from last week's NASA press conference about Artemis II decisions and plans. The space agency decided to fly Orion's heatshield as-is and continue launch preparations, while also announcing that extra Orion processing work pushed the target date out to April 2026.

In this video, I'll go over how NASA plans to fly the existing heatshield on Artemis II, given the char loss/spalling issues seen with the same design on Artemis I. I'll also cover that extra processing work and what a new re-entry trajectory means for Artemis II launch windows.

In the meantime, the SLS Core Stage for Artemis II was moved into a new processing cell in the Vehicle Assembly Building at Kennedy Space Center, and I'll go over that process and what work is planned in parallel with the resumption of Solid Rocket Booster stacking in another cell in the VAB.

There's also a little more to say about the devil in the details of moving Orion to another launch vehicle, if the new administration terminates SLS.

Imagery is courtesy of NASA, except where noted.

00:00 Intro
00:37 Artemis II-related takeaways from last week's heatshield decision press conference
06:11 Second round of Orion vacuum testing complete, modified batteries reinstalled
07:37 The modified Orion re-entry trajectory plan for Artemis II
15:27 SLS hardware activity picks up in the Vehicle Assembly Building
18:15 EGS launch team continues countdown simulation training
18:37 The Artemis II big picture
19:45 More IRL considerations for Orion launch vehicle match-making from the last time NASA considered it.
26:16 Thanks for watching!

Edited to add: Many of the pad-tests could've been expedited if the SLS/Artemis programme planners had planned for and funded its equivalent of the Apollo programme's SA-500F Facilities Integration Vehicle.

 

[Flyaway]

Introducing Endurance: An Enduring Long-distance Robotic Lunar Rover

www.leonarddavid.com

Meet Endurance, a pioneering NASA moon rover designed to survive the frigid lunar night

"Endurance is a mission that pushes the envelope."

www.space.com