totm dec 2023 Artemis Discussion Thread

[tater]

Bigger issue is still the heat shield, IMO. For all the talk about the "right way" to test all the things, SLS/Orion people seem awful quiet about testing arguably the most critical component for crew safety with a crewed flight test.

 

[darthgently]

4 hours ago, tater said:

Bigger issue is still the heat shield, IMO. For all the talk about the "right way" to test all the things, SLS/Orion people seem awful quiet about testing arguably the most critical component for crew safety with a crewed flight test.

 

Yes, failing faster should, as a hard rule, be uncrewed

[AckSed]

The blog An Ex Rocket Man's Take On It has a post on ablative and other heatshields, but (so he says) here's the key difference between EFT-1 and EM-1:

Quote

A very close variant of the Apollo material was initially chosen for the new Orion capsule,  designated Avcoat 5026-39HC/G,  which is the same epoxy-novalac resin filled with the same quartz fiber and phenolic micro-balloons,  hand-gunned into the cells of the same phenolic honeycomb.  There are more than 300,000 such cells in the heat shield of an Orion,  so the labor to hand-gun this stuff is very large and expensive,  and the quality of the results varied among the various individual “gunners”.  This heat shield flew on the first Orion flight test EFT-1,  and was very successful.

To address the labor expense and variability,  a variation was flown on the second Orion flight test,  which was the first Artemis program flight EM-1.  For this heat shield,  the Avcoat was made in tiled blocks of cured filled resin,  without the honeycomb.  300 of these tiled blocks were bonded to the capsule substrate for that flight.  Without the reinforcing effect of the honeycomb,  this was less successful than hoped.  The erosion rate was higher and more variable than expected,  with charred material coming off erratically in larger discrete chunks,  instead of steady loss of fine char granulate eroding away.  Apparently,  deleting the honeycomb reinforcement was a design mistake!  This issue will have to be addressed before flying the first manned Artemis mission,  EM-2.

 

[tater]

Given the dev model of SLS/Orion, I honestly don't see how they can fly without testing a new heat shield.

The break stuff, iterate model requires being hardware rich, and actually flying. That's not this program.

[AckSed]

Gateway space station progressing to 'well-shaped tin can' status: https://www.nasa.gov/image-article/gateway-illuminating-the-future/

Spoiler

 

[tater]

 

[DAL59]

It so sad finding a song lamenting the lack of crewed exploration since Apollo- and realizing it came out much closer (1990) to the end of Apollo than to today

[tater]

 

[Exoscientist]

The sh*t just got real: according to OIG, Artemis IV, the first landing mission, can’t happen until 2029 because that’s how long it’ll take to get the needed ML-2 ready:

https://youtu.be/-i0EH1ibCVg?si=NllGFepDET88aIBv

 But China plans to land men on the Moon BEFORE 2030:

China plans to put astronauts on the moon before 2030
News
By Sharmila Kuthunur published May 31, 2023
https://www.space.com/china-moon-landing-before-2030

Then China beating us back to the Moon is not just a theoretical possibility. It is now a REAL possibility.

  Bob Clark

Edited September 1 by Exoscientist
Clarity.

[Minmus Taster]

8 hours ago, Exoscientist said:

The sh*t just got real: according to OIG, Artemis IV, the first landing mission, can’t happen until 2029 because that’s how long it’ll take to get the needed ML-2 ready:

https://youtu.be/-i0EH1ibCVg?si=NllGFepDET88aIBv

 But China plans to land men on the Moon BEFORE 2030:

China plans to put astronauts on the moon before 2030
News
By Sharmila Kuthunur published May 31, 2023
https://www.space.com/china-moon-landing-before-2030

  Bob Clark

[Exoscientist]

Robert Zubrin has noted that the SuperHeavy/Starship can do Moon and Mars missions with no refueling flights nor SLS required if given a smaller 3rd stage that would actually serve as the lander, a mini-Starship if you will:

Dr. Robert Zubrin - Mars Direct 2.0 - ISDC 2019.

https://youtu.be/9xN1rqhRSTE?si=8unKEkYOxl4gQT0i

 Then it is important to keep in mind SpaceX has an existing stage that can serve for the purpose in the fully man-rated Falcon 9 upper stage. But you need the higher payload capacity of the expendable SH/SS at ca. 200 to 250 tons to be able to do it in a single launch. This is quite remarkable when you consider Elon has said the launch of the SH/SS only costs ca. $100 million.

 Then the implication is if the upcoming IFT-5 in a few more days were stripped of reusability systems so that it’s payload capacity was 200 to 250 tons, then that launch itself with a Falcon 9 upper stage as a Earth departure stage/lander could do a demonstration mission for single launch missions to the Moon or to Mars.

 We could have Moon or Mars flights now at costs we are spending for flights to the ISS.

  Robert Clark

[RCgothic]

Again, sure, if all we wanted to do was repeat Apollo. But we don't.

[Cuky]

It is not about going to the Moon, that has already been done half a century ago. It is about going to the Moon again and again and again and staying there and doing work or going for q nice spa day under the starry sky. And that won't happen if we just do what Apollo did.

[darthgently]

From another angle, with Starship, we could do an Apollo-ish "Ceres Direct" or elsewhere, but we'd need to solve all the long crew journey issues which are not trivial.  But we want those solved anyway. 

Mars and bigger orbitals are the obvious next goals after the Moon for permanent presence, but if additional funding was there, a yay-we-landed-ppl mission to Ceres or similar would be darn cool.  It is a matter of priorities though.   

The deep pockets involved have prioritized reasonably in my view, that is Moon, Mars, and bigger orbitals.   They don't have much interest in mere flag plantings and that seems rational

[tater]

37 minutes ago, darthgently said:

From another angle, with Starship, we could do an Apollo-ish "Ceres Direct" or elsewhere, but we'd need to solve all the long crew journey issues which are not trivial.  But we want those solved anyway. 

Mars and bigger orbitals are the obvious next goals after the Moon for permanent presence, but if additional funding was there, a yay-we-landed-ppl mission to Ceres or similar would be darn cool.  It is a matter of priorities though.   

The deep pockets involved have prioritized reasonably in my view, that is Moon, Mars, and bigger orbitals.   They don't have much interest in mere flag plantings and that seems rational

Martian moons are also a possibility. I don't subscribe tot he "space race" narrative that has been used in the last few years—even though I realize it's a move to secure more budget, I can't get all that excited abou the "race" to land the 11th human on the Moon.

[darthgently]

On 9/4/2024 at 9:45 AM, tater said:

Martian moons are also a possibility. I don't subscribe tot he "space race" narrative that has been used in the last few years—even though I realize it's a move to secure more budget, I can't get all that excited abou the "race" to land the 11th human on the Moon.

Agreed.  Though I can certainly see having a better established presence on the Moon, preferably sooner, for purely geopolitical reasons.  To maintain a strategic and economic balance, not for horses dogs and ponies

Edited September 5 by darthgently

[tater]

30 minutes ago, darthgently said:

Agreed.  Though I can certainly see having a better established presence on the Moon, preferably sooner, for purely geopolitical reasons.  To maintain a strategic and economic balance, not for horses and ponies

Yeah, I'm all-in for a sustainable human presence on the Moon, I'm pretty uninterested in 2 people walking around for a few hours every couple years, however.

[RCgothic]

4 hours ago, tater said:

Yeah, I'm all-in for a sustainable human presence on the Moon, I'm pretty uninterested in 2 people walking around for a few hours every couple years, however.

This

[Exoscientist]

On 9/4/2024 at 6:11 AM, Cuky said:

It is not about going to the Moon, that has already been done half a century ago. It is about going to the Moon again and again and again and staying there and doing work or going for q nice spa day under the starry sky. And that won't happen if we just do what Apollo did.

 The capabilities of the expendable Superheavy/Starship are spectacular, 200 to 250 tons to LEO now. What’s even more astonishing is the cost is only in the $100 million range. This means we can send a manned-capable Mars mission not in the 2030’s but literally in just a few days with the IFT-5 stripped of its reusability systems to get that max payload with an F9 upper stage strapped atop it, and for costs for what we spend to send astronauts just to the ISS.

 The dream of manned flights to Mars is already here. All that is required is to recognize it.

   Bob Clark

[GuessingEveryDay]

1 hour ago, Exoscientist said:

 The capabilities of the expendable Superheavy/Starship are spectacular, 200 to 250 tons to LEO now. What’s even more astonishing is the cost is only in the $100 million range. This means we can send a manned-capable Mars mission not in the 2030’s but literally in just a few days with the IFT-5 stripped of its reusability systems to get that max payload with an F9 upper stage strapped atop it, and for costs for what we spend to send astronauts just to the ISS.

 The dream of manned flights to Mars is already here. All that is required is to recognize it.

   Bob Clark

The next launch windows for the Mars transfers start in October. That's when New Glenn is planning to launch. So Elon Musk probably tries another Falcon Heavy test, and sends all of the Tesla S3XYCARS to Mars on IFT-6. Could it happen? Probably not. At the same time, @Ultimate Steve predicted Elon Musk sending a Tesla to Mars a few months before Elon actually announced the plan. Who's to say I'm right about this one?

[Ultimate Steve]

Still very happy about that.

[tater]

I see no reason to launch a car to Mars with a ~$100M SS/SH stack. They will continue to move the ball down the field, the goal is reuse.

[darthgently]

2 hours ago, tater said:

I see no reason to launch a car to Mars with a ~$100M SS/SH stack. They will continue to move the ball down the field, the goal is reuse.

I could maybe see launching an entire self deploying modular basecamp  with attached pressurized garage with an Eddie Bauer Mars Edition Cybertruck in it and land it on some primo Martian real estate and then raffle off the deed to this Mars Man-Cave-Base for charity.  The winner just has to get there somehow to enjoy it

Edited September 5 by darthgently

[Exoscientist]

 A great influence in developing funding and support for space among the public is psychological:

Scenario 1.):

Public: When can we have continually inhabited stations on the Moon? 
 Answer: maybe we can send the first landing mission in 2029. But it’ll cost perhaps $8 billion per mission amortized over total program cost like Apollo did, in current dollars, and wind up being cancelled like Apollo was.

Public: When can we send manned missions to Mars? 
Answer: maybe by the 2030’s.

Scenario 2.):

Public: When can we have a continually inhabited stations on the Moon? 
Answer: we can launch a manned mission tomorrow. They’ll cost in the range of $100 million per flight, comparable to flights to the ISS. So we can have continually inhabited stations on the Moon tomorrow.

Public: When can we send manned missions to Mars? 
Answer: we can launch manned missions tomorrow. They’ll cost in the range of $100 million per flight, comparable to flights to the ISS. So we can launch them, in fact several of them, every two year launch window.

 

 Robert Clark

Edited September 6 by Exoscientist

[tater]