As we approach the first flight on Monday (if it doesn’t turn out to be the second wet dress rehearsal that they probably should have run), Eric Berger has thoughts.

But whether the flight is successful or not, Artemis is not a serious program. I disagree with John Logsdon, though:

The lander will also require multiple refuelings en route to make the journey to the lunar surface. That will “require four or five or six launches to put the fuel into orbit,” noted John Logsdon, founder of George Washington University’s Space Policy Institute, adding that means “a lot of places for failure.”

If a propellant launch fails, you do another one. No big deal.

[Thursday-morning update]

An interview with Lori Garver.

32 thoughts on “SLS/Artemis”

  1. Why even wait for the lander to start launching propellant?

    You could top off the 1st tanker with the other 5 tankers and then let tanker 1 fill the lander as soon as it makes orbit. You don’t even launch the lander until the temporary depot aka tanker 1 is full and waiting.

    1. The problem with a propellant depot is boil-off. No matter what you do, some of your oxidizer or fuel will turn to a gas, and will need to be vented to keep the tank from rupturing. A depot needs a continuous stream of shipments to refill it, and a continuous stream of rockets being refilled.

      It’s a bit of a chicken-and-egg problem. Putting up a depot now is a bit like putting a gas station in before the highway is built.

      1. Boil-off is a solved problem, especially for methalox. Starship is intended to travel to Mars and land using fuel and oxydizer brought from Earth. Are we picturing SpaceX engineers launching a crew toward Mars, then clapping a hand to their foreheads and shouting, “D’oh! We forgot about boil-off!”

        A depot would be shaded from heat sources (or, as in the case of Lunar Starship, painted white), have its own power source (external to the shade) and an on-board recondenser. For launch vehicles, the recondenser is part of the ground-support equipment. This is how it’s done for SuperHeavy. Starship will have to have an on-board recondenser, and either batteries (for short trips) or solar panels.

        Older-style cryogenic launch vehicles were full of boiling fuel and oxydizer and had to vent and be topped off (e.g., the vent-cap for STS). Falcon and Starship use subcooled propellants and Starship circulates through a recondenser. Falcon does vent oxygen, but its subcooled RP-1 is recirculated.

        That is how it will work with the Accummulation tanker, and I expect to see it painted white, as it’ll only have to last a week or so between fill/drain operations.

  2. Logsdon is a terrific space historian. But he seems to be captive to his generation’s space paradigms.

  3. “If a propellant launch fails, you do another one. No big deal.”

    Assuming they were allowed to. But really, the probability of a launch failure is the issue, not so much that one happens because a certain number are needed for a specific mission.

    Spaceship and Super Heavy will have a high flight rate and will need to be reliable for this to happen. We can’t assume SpaceX will have no problems but we can assume they possess the skill to address anything that arises and have demonstrated they can make a reliable launcher. It is not like their only launch experience will be doing a mission for NASA every year or two. There will be a lot of real world data to prove reliability.

    I get the notion of the type of statistical risk involved but it is unlikely it will be significant or meaningful enough to not use the launcher. This is especially true if the alternative doesn’t have any real world data to back up predictions of reliability because the flight rate is so low.

    1. They are also producing new Raptor 2 engines every day or two with intent to get faster at it. That’s an assembly line that can make incremental changes quickly and get improved products in service much faster. A Raptor engine failing on a test stand doesn’t scare them, because it simply is new data that can improve the next ones coming off the assembly line. For NASA, losing a single RS-25 engine is one less flight on the manifest, and they’ll lose 4 each mission anyway.

      Speaking of RS-25, there is this line in Eric Berger’s article: “It took the agency 11 years to go from nothing to the Moon.” Let us count the wrong in this one sentence:
      1) SLS was sold as reusing STS technology, so not exactly nothing (although to be fair, they so heavily modified each component to be nearly enough a new design).
      2) SLS is a variation of Ares V, which started the design process earlier than 11 years ago and again means NASA didn’t start with nothing.
      3) Oh yeah, Orion was even earlier and it is the only part headed to the moon.
      4) NASA hasn’t made it back to the Moon yet, so those years are still counting.
      5) “To the Moon” is poorly defined. Artemis I will only fly around the Moon and not to the ground, making it hardly different than many other satellites. Artemis II will do the same, but this time with people so a bit more than any other satellite in the past 50 years yet still not to the ground. 3 years from now, maybe NASA will actually get people back to the lunar surface, but that’s assuming all these earlier tests happen without issue and every other technology is developed in time.

      I have a lot of friends that still work at NASA. I know a successful launch will be a cause of celebration. No matter your thoughts on the value of NASA, there are individuals really working hard and contributing the efforts they can for what they consider a value to our nation. I do wish them well. I’m just glad my career is no longer tied to this endeavor nor riding on the hopes of a successful launch.

      1. “To the Moon” is poorly defined. Artemis I will only fly around the Moon and not to the ground, making it hardly different than many other satellites.

        Yeah, the analogy of Artemis 1 is to a sort of combination of Apollo 4 (November 1967) and Apollo 8 (December 1968). So, shave a year or two off the Apollo timeline.

        Doesn’t really help SLS’s timeline comparison, though!

      2. Nice comment. Even though I want to see SLS cancelled, I want it to go because of cost reasons and better alternatives and not because of launch failures. I wish them well too and they should be proud of their work. Building rockets isn’t easy and not many people get the opportunity.

        But TBH, I can’t muster much outrage about the cost when the budget has been busted so many times over the last twenty years. Every little bit adds up but NASA is such a teeny tiny part of the problem.

      3. Eric’s remark was referring to NASA’s founding in 58 and the landing in 69. Apollo, not SLS.

        1. I can accept that, because of the following sentence, but the preceding statement suggests this topic is about SLS. For others, who may not click to read it, here’s the entire paragraph:

          So here we are, nearly a dozen years after that authorization act was signed, and NASA is finally ready to launch the SLS rocket. It took the agency 11 years to go from nothing to the Moon. It has taken 12 years to go from having all the building blocks for a rocket to having it on the launch pad, ready for an uncrewed test flight.

          I think my points still stand, although Eric was perhaps trying to make the same point in three sentences.

  4. Like I said. Launch the propellant first, the Starship lander second and the Orion third. That way, the propellant delivery is assured before you commit the more critical resources and people.

  5. Eric’s piece is interesting, in that it fleshes out some thoughts he has voiced in various ways over the past year or two.

    Now, we all know how SLS has been the *worst* thing to happen to NASA. That is not news. It is not hard to figure out. But the more intriguing claim is that it has been the *best* thing to happen to NASA.

    Berger only dances around that at the very end of the article, basically as an afterthought. But a redditor named Paul Williams yesterday reworked this idea into a more concrete form that seems worth sharing here:

    1. SLS forced Nasa [Or rather, the Trump Administration] to improvise an adaptation to using that launcher for the newly defined Artemis lunar program.

    2. Starship was the only available lunar lander option which Nasa was then forced to choose and Congress had to accept for SLS not to be out of a job.

    3. This forced the previously-ignored Starship to center stage, and implicated Nasa in its success.

    4. Ensuing blowback from Congress led to the addition of a legacy space offering for the NEXTstep Artemis followup in which Starship is already a part.

    5. This creates the situation where the New Space (Starship) vs Legacy Space comparison will be made in full view of the US and world public.

    6. It gifts Nasa with an honorable exit from Legacy Space as it hands over to New Space during the crew transfer between Orion and Starship.

    7. It keeps Nasa in the game as Starship and its future lookalikes become the backbone of interplanetary flight.

    I think there is something to this. The sad aspect is that staggering opportunity costs this outcome requires. But it could well be that, politically, something like this is the best outcome we could reasonably have hoped for.

  6. SLS has been wildly successful. It kept congress and big space off Elon’s back. The public trough was kept full for the usual leeches and glory-hounds until Starship got developed.

  7. Human Mars exploration with nuclear propulsion is inevitable!

    It seems to me that chemical propulsion is inevitable-
    particularly if starting from LEO.
    It’s seems chemical provides enough thrust to leave LEO.
    With Ion engines one can spiral out or taking a longer
    time one bump up to higher orbits with short duration burn. And could do same nuclear thermal propulsion with it’s lower thrust.
    And though one has the longer time to bump up to higher orbits, one could do this also with chemical rockets {no one appears do this with chemical rockets or yet, with any other kind of rocket engines}.
    It appears the main advantage of efficient low thrust is
    to reduce amount mass one needs to get to orbit.
    But if have large rockets cheaply get mass to orbit, then it reduces that need.
    And if can refuel in orbit, it reduces that need even more.
    What is promised is nuclear [or ion] can get to Mars faster [100 day or 60 days].
    I like idea to getting to Mars within 90 days or less.
    Mainly because it seems to me, politically better for NASA exploration of Mars.
    This assuming NASA wants to explore Mars in near future, and not continue what it’s been doing for decades- saying going to do it soon, and not do it soon.
    Or if NASA wants to waste more time, spending time developing nuclear rockets, would be a way to waste a lot more time.

  8. Here is my opinion:

    They HAVE to launch the thing because they have to have something to show for all the wasted billions and man hours.

    If it fails, they will have an excuse to end the program.
    And perhaps they will.

    If it succeeds, it’s another couple of years for the next flight -2024. And the next is 2025. Plenty of time for Space-x to get going with Starship. At that cadence SLS a useless tech. Most of the graft will have been squeezed from it. So they will end it. Or the subsequent flight program will slow down even further.

    In 5 years other launch systems will make SLS even more obsolete than it already is today. SLS will end.

  9. “But I do think that as the public starts paying attention, they’re going to have a lot of questions. So far, I don’t think people beyond our community really know what’s happening.”

    Years ago, I thought the public would be upset over the gap between ending and restarting the domestic capability to launch humans into space. I thought that the longer the gap, the more upset the public would be. It turns out no one cared. I think they would have cared if when the recent war in Ukraine broke out, that we were still getting rides from Russia. But no one cared about the gap. No one cares about the sorry state our crew transport is in or how much has been wasted on SLS/Orion.

    Social media, especially YouTube, has enlarged the space fandom, so maybe not caring will change over time. Even there, people aren’t concerned about the big picture, fiscal sanity, or limits of ideology. Most everything is cheerleading regardless of rationality and to the extent pondering takes place, is in the context of dystopian views of the existence of humanity.

    The best development out of all of this has been the reduction of political control over space based activities so that ideological battles over how to spend tax revenues is trending toward being less powerful than whether or not someone thinks they can engage in voluntary cooperation to fund the pursuit of their space based desires. Command economies don’t work. There is still a lot of work to be done to keep the momentum going in this direction.

    1. Politically, it could important to have settlements on Mars.
      But it seems there are lot things to happen to have settlements on Mars.
      One of those things is having ocean settlements on
      Earth. And Ocean settlements, politically could be more significant, than having settlements on Mars.

      In terms humans transforming into space spacefaring civilization. Which a big thing politically- like no war on Earth, ever – kind of big thing.
      Settlement in Venus orbit seems to part of this- it seems most of human population could live in Venus orbit. Most human living in Venus orbit and most humans on Earth living on the ocean- or I say, low income housing living on the beach.
      It seems Venus orbit is desirable to have access to, when exploring Mars, and later with Mars settlements.
      Using Venus orbit increases Earth to Mars launch window [by going from Earth to Venus to Mars and going from Mars to Venus to Earth].
      Or in terms of hohmann type travel, Venus is faster to Mars than Earth is faster to Mars.

      Venus orbit is where you bring the solar system’s
      water. And it seems in the race to get cheaper water than water on Earth, it seem Venus orbit gets there faster. But before this, Mars will have cheaper water than anywhere other than Earth. And Mars can export water to Venus orbit [or Venus water costs more] but the solar system has a lot more water than Mars or Earth has. And it seems first stop for Solar system water, would be Venus orbit.
      So first trillion tons of water mined beyond Earth, belongs to Mars. But it’s trillions of tons after that which will delivered to Venus from places other than Mars.


        Venus to Mars:
        Trip Time 0.5954 Years

        Earth to Mars
        Trip Time 0.7087 Years
        So, 365 days times 0.7087 = 258.6755 days
        divide by 30 days = 8.622516667 months
        We can get to Mars a lot 8.6 months.
        We do 7 months and SpaceX says 6 months.
        And from Venus to Mars we can likewise do it faster
        than 0.5954 Years
        365 times 0.5954 = 217.321 days
        divide by 30 = 7.244033333 months
        How much faster with patched conic from Venus
        to Mars?
        The general answer should be a lot faster.
        Venus to Earth
        Trip Time 0.3999 Years
        365 / 0.3999 = 145.9635
        145.9635 / 30 = 4.86545 months
        We have got to Venus faster than that, but it’s more improvement as Earth to Mars, faster. Or not as much as improvement as Venus to Mars improvement.
        Now compare Starship from LEO to Mars in 6 month
        to Starship from High Venus orbit to Mars.
        Using same delta-v from high Venus as one uses from Low Earth orbit to Mars. It seems one beat 6 month and hit atmosphere at lower velocity.
        And how if used more delta-v and hit Mars at same velocity as you would from Earth to Mars.
        So dropping high Venus, to distance from Venus to low distance from rocky surface, and added the delta-v to get to Mars. And seems it should be around 3 months to Mars.
        It seems to me, from Earth high orbit, one could do a non hohmann to likewise get to Mars in 3 months.
        But it take a lot more delta-v [and don’t hit Mars atmosphere fast- don’t need starship’s braking ability. But one also do something like that from Venus high orbit, also.
        But with Starship one get from Earth to Venus quite fast, using Venus atmosphere to slow you down, so somewhere around 2 months to go from Earth to Venus.
        But main point is reducing a Earth to Mars or a Mars to Earth window from 2.1 years to average of about 1 year [it varies] if use Venus orbit.
        Or by having refueling and artificial gravity station at Venus orbit, 1/2 Earth to Mars window. AND lower radiation and lower microgravity issues of going to Mars from Earth [if and when you use Venus orbit].

  10. Can you make a stick artificial gravity station by attaching two starship second stages together?
    And/or bring something to extend the radius, by say 20 meters. Or by 100 meters?
    Also this seem like better way of refueling in orbit?

    I have mentioned before, that I think it would be best
    to test this, by using the second stage of falcon 9 rocket. Add to height of second stage, and give a living area with floors attached to second second, and use both spend stage and added floor as small stick artificial station. And see how it works making up to Mars level artificial gravity, And if doesn’t work, extend it, by use rope/cable attached dragon and end of floored section. Or with a rope one could add another 50 meter to the radius.
    Some sort of adventure, not particularly more adventurous than crew on the Moon or Mars.

  11. To the extent that there is a race here, the race will be won by whomever makes their second launch first. It’s that second launch that drives home the economics, the sustainability of the program, and the commitment to meaningful goals. There is no way that SLS can win this.

    1. Starship will be confined to LEO until, it can refuel in LEO.
      SLS is only doing NASA mission for say next 5 years, at least so unless NASA wants SLS do something else, SLS will busy with it’s assigned missions [and probably if history a guide, be delaying these future launches]

      Let’s see:
      “After the first four Artemis missions, NASA plans to transfer production and launching of the Space Launch System to Deep Space Transport LLC, a joint venture between Boeing and Northrop Grumman.”
      So, one say it’s not “There is no way that SLS can win this.” but rather there is no way that LLC can win
      “Deep Space Transport LLC would be responsible for producing hardware and services for up to 10 Artemis launches beginning with the Artemis 5 mission, and up to 10 launches for other NASA missions. ”
      The LLC will have different upper stage:
      The Exploration Upper Stage (EUS) is being developed as a large second stage for Block 1B and Block 2 of the Space Launch System (SLS), succeeding Block 1’s Interim Cryogenic Propulsion Stage. It will be powered by four RL10C-3 engines burning liquid oxygen and liquid hydrogen to produce a total thrust of 433.1 kN (97,360 lbf). As of October 2017, the SLS Block 1B will have a payload capacity to low Earth orbit of 105 t and Block 2 will have a payload capacity of 130 t. The EUS is expected to first fly on Artemis IV in March 2026

      So, Starship should it’s second launch before the end of 2023 {it might launched 20 of them before end of 2023]. And it might be working out refuel starting in 2024.
      If SLS launches within month and is successful in completing it’s task. It should continue until well after 2024. If can’t get into orbit, and go around the Moon and have it’s capsule safely land back on Earth- there could more doubt that it would make it to 2024.
      I think there is 50% or more chance SLS will successfully launch on Aug 29. And if not, a 70% chance it launches before end of 2022.
      And so, if and whenever SpaceX is refueling Starship in LEO, and SLS has successful launched, SLS will still going. And wouldn’t ruled SLS not launching a couple of the Exploration Upper Stages.
      NASA is expected to issue an award by Dec. 31, 2023 to Deep Space Transport LLC
      If SLS doesn’t have major problems before Dec. 31, 2023, it probably be awarded [though could be modified]. But if SpaceX is refueling in LEO before Dec 31 2023, it might be different.
      But I don’t think Musk is planning that happening. He seems to want as many LEO launches delivering delivering Starlink Version II as can manage, before 2024.

  12. It’s very much worth noting that SapceX’s *actual plan* is as follows:

    1. Launch Accummulation Tanker to LEO. Notice the word “depot” is not used? I wonder why?

    2. Launch reusable tankers to fill Accummulation Tanker. Collect contract payment from NASA when transferred fuel exceeds 10 tons. The exact number of tankers to fill the AT depends on how much fuel each regular tanker can lift. Probably 4 or so. The fantasy that it will be 20 comes from certain people on NSS.

    3. Launch Lunar Starship and refuel from Accummulation Tanker.

    4. Fly to cislunar space.

    (4.5. Pick up crew, if it’s Artemis III or later.)

    5. Land on Moon. Collect milestone payments from NASA.

    1. 1. It isn’t a depot, it’s a stage being refueled in orbit. A depot would be a different design, much bigger than any ship refueling there, because it would need many tankers delivering and many ships refueling, often at the same time. It will be used to demonstrate the technology in orbit, bringing the tech to TRL 9. Expect at least one explosion before they get it right.

      1. That’s a quibble. It could be left up to service many missions, in which case it’s a depot. Just a little one. They couldn’t call it a depot because a certain Alabama senator said so.

  13. The end of Death and taxes:
    Episode 1847 Scott Adams: Redacted Affidavits, Rogan Talks to Zuckerberg, Student Loan Forgiveness

    If there is a end of death. you would would to decide to die- it seems that might hard to decide.
    And end of taxes, you have to decide what you want to waste a lot money on.
    Sounds almost like work.
    I agree it’s coming, but there is good chance I will be dead before this happens.

  14. I saw an interesting speculation the other day: When NASA is done with the uncrewed HLS demo, refill the Accummulation Tanker, load the last tanker from it, and rendezvouz with the prototype lunar starship (a.k.a. Skeletor) in lunar orbit, refuel it (there’d be about 150 tons available) and fly Skeletor off to Mars. Try to aerocapture at Mars and land on Phobos. The lunar tanker could be used to see if it can do EDL on Earth (required before dearMoon can fly).

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