SpaceX Renders Metal Starship on Moon and Mars

Elon Musk has tweeted out new SpaceX computer-generated pictures of the metallic Starship on the Moon and Mars.

The SpaceX Spaceship is the upper stage of what was called the BFR. It is being made with a steel alloy that is easier and cheaper to work than carbon composites.

The SpaceX Starhopper is already testing the new Raptor engine which has about double the thrust of the current SpaceX Merlin engines.

The rapid pace of SpaceX construction and testing could see a launch to orbit of a Starship by the end of this year or early next year.

The combined SpaceX Super Heavy Starship (what was called the BFR) will be 100% reusable and will drastically lower SpaceX cost to space. It will be able to launch 100 tons into low earth orbit.

SOURCES- SpaceX, Elon Musk Twitter
Written By Brian Wang

44 thoughts on “SpaceX Renders Metal Starship on Moon and Mars”

  1. I very skeptical about digging up ore and reducing the LOX out of it. It’s mechanically difficult and energy-intensive. I’m a lot more comfortable with mining water by basically microwaving it from cold traps and hoovering it up (using still more cold traps).

    We’ll get to the point where LUNOX reduction is viable, but you need to walk before you can run.

  2. I like this idea better–but scaled up for Mars: 

    I have heard it said that some of the production V-2s had a rough surface due to the unwilling hammer blows of the forced labor, yet they were smooth compared to Starhopper.

    I don’t have a problem with Starhopper’s appearance because it isn’t about looks.

    But still…

    If none of the usual snarky posters at space websites knew who or what Elon/SpaceX was, and you showed them a picture of Starhopper (the same rocket mind you)–but told everyone it was from Russia, (or worse…North Korea)– the internet hate would be pitiless.

    Oh, the cutie pie remarks write themselves….something to the effect about building a laughable 1950s-ish finned contraption on a dirt pile using pallet jacks, cranes and sheet metal, etc.

    But on the flip side, maybe there would be more love on the web shown to Old Spacers about the tried and true “Gradatim Ferociter” approach.

  3. If I’m understanding you, you’re proposing kind of a skirt of framework and drop tanks around the back of the Starship? That’s… kinda weird, but I’d be interested in seeing the numbers.

    I can think of a few problems right off the bat:

    1) Starship is pretty close to the point of diminishing or even negative returns on extra prop when it needs about 9000 m/s of delta-v to get from LEO to the surface and back. Even adding small amounts of dry mass for the skirt might actually reduce your total delta-v. You have to be very careful with the numbers.

    2) You’re talking about a structure that almost certainly couldn’t be shipped in a Starship–at least not without cis-lunar assembly. And then you have to ferry the extra prop out. Add in dry or wet workshop costs and it’s hard to figure if it’s worth it. Again–numbers.

    3) If you launch the Starship from inside this rat’s nest, how do you keep it from blowing the structure apart? It’s not like you can dig a flame trench…

    There’s a lot to be said for transshipping nice, well-contained cargo containers that have 800 m^3 of volume and about 150 t of mass, with a Starship on one side of the exchange and a lunar ferry on the other.

  4. It’s an interesting analysis.

    My reply would be that the purpose of my proposed “lander”, is to solve at least some of the issues you identify.

    1) It acts as a drop tank for the Starship, to allow greater delta-V. I haven’t run the numbers yet, but it should be possible to avoid that highly elliptical orbit you’re concerned about.

    2) It increases the mass of the Starship while attached, lowering the minimum acceleration, so that hover-slamming onto the Moon is no longer an issue, even using two engines.

    3) It increases the width of the base on landing, to allow stability in landing on an unimproved surface.

    4) It can function to protect all but the engines used during the landing.

    5) After landing it IS the Moon base. This means the extra mass, aside from *maybe* the tankage, is not wasted. It’s cargo. Likely the tankage can be used, too, if they’re going to try to manufacture propellant on the Moon.

    6) On takeoff from the Moon, it’s your hold down hardware, you disconnect after your engines are up to minimum throttle and behaving properly.

    I’m assuming here, of course, that the Starship is designed to allow the use of an external fuel supply. It is refuelable, of course, so that’s at least plausible. I’m also assuming mounting hardware near the bottom to attach the drop tank/base to.

    What’s the advantage of this proposal? What has to be developed isn’t a complete vehicle, the Starship IS the vehicle. And the Starship IS going to be developed anyway.

  5. If you’re going to do development of yet another lander, it seems to me that you’d do much better just developing an optimized lunar ferry.

    Starship is as big and heavy as it is because it needs to take off from Mars. If all you’re doing it going between the lunar surface and a Starship in cis-lunar, you can make something can carry the same amount of cargo as Starship, is much safer and more flexible to operate on or near the surface, and with a dry mass that’s less than a fifth of Starship’s.

    Just to be clear: I don’t think attaching a landing stage to Starship makes a lot of sense. But transferring cargo and/or crew (I’m pretty sure that crew on a Starship will wind up being handled like cargo, with a tuna-can-like module (StarKist!) that can be loaded like any other payload. If that’s the case, then it’s easy to send a ferry up, transfer the various payloads to it (essentially just stacking them onto a pallet with an engine and prop tanks on the bottom), and then both go their separate ways.

    If you’re interested, here’s my analysis of how to use Starship ASAP for a lunar program:

  6. The one where the Sun looks “too small” is the Mars illustration, not the Moon illustration. The Sun really does look small on Mars, it’s much further from the Sun than Earth is.

  7. I’m not saying it wouldn’t require development. For one thing, it would change the ship’s moment of angular inertia, requiring the control software to be tweaked to take it into account.

    And you couldn’t do the testing on Earth, I would have to be tested under the appropriate conditions, vacuum and low gravity. The Moon, IOW. Definately want to do that unmanned!

    The point is, though, it’s not just a piece of equipment to help with the landing, it IS the Moon base, or a segment of it. That means to a large extent the development effort is baked into the Moon base program anyway.

  8. Yeah, that’s pretty much my thinking. But it’s another lander. It’s fairly expensive to develop. It’s even more expensive to crew-rate.

    I hate to be a constant wet blanket, but this stuff is genuinely hard. Blithely assuming that a platform as complex as Starship will magically solve all problems, from launch to transit to landing to reentry, all in one swell foop, is way up there on the optimism scale.

    I think Starship can be almost instantly valuable ferrying crews from LEO to cis-lunar and back. But it’s gonna take a while before all the kinks are ironed out on all the different modalities in a lunar mission profile.

  9. Yeah, the lunar floor is in pristine state, when it should have some visible recently dug out crater.

    That’s the most unrealistic part of the picture.

  10. Musk is an entrepreneur who made his American dream come true. He is a libertarian and patriot who will market rockets, cars and flame throwers – of course he is going to put an American flag on his rockets.

    As James stated the only problem I see is should be bigger!

  11. Wow! The Sci-Fi movies and Analog from the 50s and 60s got it right. Big sleek looking rockets with fins landed in the upright position.

  12. That’s why I’ve suggested that, for the lunar landing, they’d unload in orbit and connect a framework extending the landing legs out sideways a good distance.

    It could incorporate the initial base, and extra propellant tanks to boost payload, (The thrust to weight ratio on the Starship is actually higher than desirable for a lunar landing! Adding extra payload and fuel tanks would improve that.), and be left behind when taking off again.

  13. They did miss the blast features you got under the landing point, though, where the exhaust was picking up stuff and throwing it out sideways.

    Got that with the lunar lander, which was relatively light. The “Starship”? It’s going to excavate a new crater as it lands.

  14. It could be done by robots controlled from the Gateway.
    I have just found first very useful thing Gateway might do.

  15. The most recent spaceX landing landed exactly on target, and then fell over because the barge didn’t stay flat.

  16. We have actual photos taken on the moon, we don’t have to argue about the theory.

    And those photos show sharp shadows… when the angle between the light and the ground is large.

    But they show blurry edges on curved slopes where the ground is shadowing itself because the surface is about parallel to the light.

    And the pictures that are above kind of look right to me.

  17. Send the rover down on what platform?

    My whole point is that you need a lander other than Starship, at least for a while.

  18. I think you’re oversimplifying by quite a bit. That might work for Mars if you brought your own hydrogen, but laying out power systems, prospecting for water, preparing access to the water, mining the water, purifying it, and electrolyzing it are quite a bit beyond the state of the art for robotics.

    Plus, there’s that whole “I hope we don’t tip over” thing…

  19. How are we going to emulate the vision of the chairman if we don’t get a rendition from time to time?

  20. Pfft that’s easy. The first BFS brings the ISRU LOX plant and does not fly back.

  21. You would need to bring the Carbon seeing how the Moon lacks it. You would also need to bring Hydrogen unless you are mining it from the poles.

    It doesn’t remove that much mass delivered to the moon to bring the methane to fly back to Earth. Most of the mass of the fuel for the return trip is Oxygen so make that on site.

  22. Would you rather another article about Trump butt-tweeting? Maybe if we click on cartoon spaceships more it will train the algorithms to do this instead of politics.

  23. It’s an unprepared landing environment to start with. It’s fine once there’s a base built up, but what delivers the equipment to build the base up in the first place?

  24. Yes indeed…
    I think it the logistics advantages of an all-purpose low ISP chemical vehicle like Starship will not outweigh the drawbacks. It will be more efficient with at least one atmospheric version and one vacuum version. Some locations will favor methalox and some (like the moon) will favor hydrolox. Without ground infrastructure and launch pads, a horizontal design would probably be more robust. The need for thrust is vastly different depending on location. Robustness and reusability issues are more difficult in high gravity atmospheric conditions etc. Landing on moons and asteroids can be done with fewer and other type of engines. Not much point hauling around 7 raptor engines and all that steel outside earth.

    Perhaps something like the old Eagle from “Space 1999” would work for low gravity and vacuum. This old sci-fi design had a high ISP nuclear drive system in the rear and supposedly chemical thrusters for the final touchdown. The cargo center section was a removable container and could be replaced with different configurations depending on mission profile.

  25. No GPS on the moon or Mars anytime soon.
    Knowing coordinates is also not enough. One have to know exactly what’s on the surface as well so careful ground based scouting is needed.

  26. It can land on a dime on earth though, so why would it be so inaccurate landing on the moon? It’s trivial for spacex to stick a GPS system up there, they could probably do it on the same launch

  27. Meh, just send some purpose-built lander-rover down to build landing pads. Why impose the rough-terrain landing capability as a design constraint on the BFR?

  28. Mostly only needs to land with enough Methane to return to earth.

    LOX comes from ISRU on the moon.

  29. This ought to give you an idea of how improbable landing a Starship on an unprepared surface will be.

    I did a rough cut at a center-of-mass model for Starship a while back, assuming that it lands with enough prop to return back to Earth. If the landing legs extend down about 3 m from the bottom of the interstage, I got a center of mass that’s about 16.9 m from the bottom of the the 51 m Starship. If SS is 9 m in diameter and the three landing legs are 5 m wide each, then the center of mass needs to stay inside the triangle with the tips of the legs as its verticies. That means that the worst case tilt distance is ((9/2)+5)*sin(30deg) = 4.75 m.

    From there, the worst-case tilt angle is arctan(4.75/16.9) = 15.7 degrees.

    The best-case tilt angle (tilting straight over one of the fins) is better: arctan((9/2+5)/16.9) = 29.4 degrees. But I don’t think you can count on being able to land with the best case.

    15.7 degrees is not good. For a little comparison, the angle of repose around a lot of the upland crater rims at the south pole is about 30 degrees.

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