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SpaceX's Dragon capsules come with engines, which (in some configurations) are sufficient for powered landings. And it's still called a "capsule."

hughes 9y ago
Powered landings after an intense atmospheric deceleration.
- kobeya 9y ago
  No, powered landings all the way down. At least on the Moon and Mars (from orbit). With more fuel you could do the same from Earth, but why bother?
  - deleted 9y ago
    [deleted]
  - robotresearcher 9y ago
    That's cool, I didn't know that. So Dragon 2 is a Soyuz-like passive capsule when landing in atmosphere and a powered spaceship like the Apollo LEM when landing in vacuum. Very cool that they could cram those roles into one vehicle. Looking forward to seeing it work.
    - Diederich 9y ago
      https://youtu.be/1_FXVjf46T8 https://youtu.be/1_FXVjf46T8 Work in progress..Well along in progress.
      - robotresearcher 9y ago
        Oh that was cool. I have a stupid grin on my stupid face now.
        Diederich 9y ago
        It really is....I'm such a SpaceX nut. (:
  - dotancohen 9y ago
    Are you sure about the orbit? Could a Red Dragon not land directly from a Hohmann transfer?
    - kirrent 9y ago
      Wikipedia seems to imply that the plan for Red Dragon is a direct atmospheric entry. It makes sense, they don't have a second stage that would last long enough to get there. They don't have the delta-V to get the second stage into a mars transfer with a huge amount of fuel and I doubt there's much utility in spending the 2.3km/s (or thereabouts) of delta-v in getting from the Mars transfer to a low Mars orbit when you can just use aerobraking instead. In fact, it would be highly abnormal for a probe to visit Mars orbit before landing.
      - dotancohen 9y ago
        There is no dichotomy in aerobraking vs orbit. In fact, I believe most interplanetary orbiters (Galileo, Cassini) used aerobraking to achieve orbit.
        zardo 9y ago
        They didn't. Aerocapture has only ever been done on Earth.
        ethbro 9y ago
        Now I'm curious to run the numbers on how lenient the window is for (I'd assume it would have to be) single pass aerocapture on Mars. And especially interested on what the options for the problem scenarios look like (e.g. burning off too much or not enough velocity).
    - kobeya 9y ago
      It could land directly, yes, but it makes use of the aerobrake for slow-down. Without that aerobrake it would not have enough fuel to do a powered landing all the way down and then return to orbit (I think -- I don't actually work for SpaceX; I'm just a fan). But it is my understanding that it has enough fuel to do a full propulsive landing from orbit and back again, without an aerobrake.
  - kirrent 9y ago
    Dragon is barely capable of landing on the moon if you remove the heat shield and replace it with more fuel and fit additional fuel storage in the capsule. Its powered descents on Mars would only be possible because of atmospheric drag.
    - trafficlight 9y ago
      It's almost as if it weren't designed to land on the moon.

hughes 9y ago

Powered landings after an intense atmospheric deceleration.

kobeya 9y ago
No, powered landings all the way down. At least on the Moon and Mars (from orbit). With more fuel you could do the same from Earth, but why bother?
- deleted 9y ago
  [deleted]
- robotresearcher 9y ago
  That's cool, I didn't know that. So Dragon 2 is a Soyuz-like passive capsule when landing in atmosphere and a powered spaceship like the Apollo LEM when landing in vacuum. Very cool that they could cram those roles into one vehicle. Looking forward to seeing it work.
  - Diederich 9y ago
    https://youtu.be/1_FXVjf46T8 https://youtu.be/1_FXVjf46T8 Work in progress..Well along in progress.
    - robotresearcher 9y ago
      Oh that was cool. I have a stupid grin on my stupid face now.
      - Diederich 9y ago
        It really is....I'm such a SpaceX nut. (:
- dotancohen 9y ago
  Are you sure about the orbit? Could a Red Dragon not land directly from a Hohmann transfer?
  - kirrent 9y ago
    Wikipedia seems to imply that the plan for Red Dragon is a direct atmospheric entry. It makes sense, they don't have a second stage that would last long enough to get there. They don't have the delta-V to get the second stage into a mars transfer with a huge amount of fuel and I doubt there's much utility in spending the 2.3km/s (or thereabouts) of delta-v in getting from the Mars transfer to a low Mars orbit when you can just use aerobraking instead. In fact, it would be highly abnormal for a probe to visit Mars orbit before landing.
    - dotancohen 9y ago
      There is no dichotomy in aerobraking vs orbit. In fact, I believe most interplanetary orbiters (Galileo, Cassini) used aerobraking to achieve orbit.
      - zardo 9y ago
        They didn't. Aerocapture has only ever been done on Earth.
        ethbro 9y ago
        Now I'm curious to run the numbers on how lenient the window is for (I'd assume it would have to be) single pass aerocapture on Mars. And especially interested on what the options for the problem scenarios look like (e.g. burning off too much or not enough velocity).
  - kobeya 9y ago
    It could land directly, yes, but it makes use of the aerobrake for slow-down. Without that aerobrake it would not have enough fuel to do a powered landing all the way down and then return to orbit (I think -- I don't actually work for SpaceX; I'm just a fan). But it is my understanding that it has enough fuel to do a full propulsive landing from orbit and back again, without an aerobrake.
- kirrent 9y ago
  Dragon is barely capable of landing on the moon if you remove the heat shield and replace it with more fuel and fit additional fuel storage in the capsule. Its powered descents on Mars would only be possible because of atmospheric drag.
  - trafficlight 9y ago
    It's almost as if it weren't designed to land on the moon.