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Why NASA's Road To Mars Plan Proves That It Should Return To the Moon First

Posted by timothy on from the one-giant-step-at-a-time dept.

MarkWhittington writes: NASASpaceFlight.com published the results of current NASA thinking concerning what needs to be launched and when to support a crewed mission to Phobos and two crewed missions to the Martian surface between 2033 and 2043. The result is a mind-numbingly complex operation involving dozens of launches to cis-lunar space and Mars using the heavy lift Space Launch System. The architecture includes a collection of habitation modules, Mars landers, propulsion units (both chemical rockets and solar electric propulsion) and other parts of a Mars ship.

3 of 194 comments (clear)

  1. Re:Hmm by sidyan · · Score: 3, Interesting

    "cis" literally means "on this side of", just as "trans" literally means "on the other side of".

    cis-lunar space can be loosely defined as that part of space that is within half a million km from Earth (which includes the Moon itself, as well as all the Earth-Moon Lagrange points).

  2. Re:Moon as a gas station by Mystic+Pixel · · Score: 5, Interesting
    So let's say the Moon is acting as a "gas station". Gas stations are great and all, but the fuel they dispense has to come from somewhere. On Earth this occurs via tanker truck. If you're arguing that "most of the mass involved in a trip to Mars consists of fuel", and therefore it would be cheaper to refuel ships at the Moon, great. You are trying to say that this makes economic sense.

    How do you account for the cost of getting "tanker trucks" to the Moon? If you want to refuel rockets on the Moon you have to get the fuel there somehow, or create it on-site.

    Currently the options for that are:
    a) mine lunar helium-3. Cool, but let's get some rockets that can use it first.
    b) spend unnecessary money to ship fuel there just so we can put that fuel into another rocket, which needs it because... it spent all the fuel going to the Moon instead of Mars.
    c) ???

    Anyone who hasn't actually read up on Mars Direct really just needs to stop commenting and do that first, so they can actually understand what the hell they are talking about. The Moon as a waypoint is completely and utterly unnecessary. It has no useful resources for this purpose other than helium-3, which we can't even make proper use of (because we're too scared of anything relating to nuclear energy to launch a damn RTG, let alone finish development on any actual nuclear engine). Doing anything on the Moon requires an absurd amount of machinery, life-support, and docking mechanisms, which are completely overkill for what you're trying to do (i.e, go to Mars, which is a balmy paradise compared to the environmental hell of the Moon.)

  3. Two points by gman003 · · Score: 4, Interesting

    First, while Mars requires a longer journey, it actually isn't substantially harder to send a rocket to than the Moon. If you use aerobraking, it's about the same delta-v. Yes, more consumables would be needed because the flight is months instead of days, which does affect the mass of the payload, but it may also be easier to build a sustainable colony on Mars (presence of an atmosphere and maybe water, higher gravity). So I don't think Luna is even really useful as a practice run.

    Second, a launch schedule like this is pretty much the only thing I've heard that could justify the development of SLS. The entire project has smelled like "big bucks on development, goes over budget or budget gets slashed so it only gets used a few times" from the beginning. If they can get Congress to give them the budget for this, yes, that would be worth making SLS for. Will Congress spring for thirty-plus Saturn V-class rockets, for only three missions? I don't think so, but I hope they will anyway.