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Moon landing with humans has been done before but on Mars there seem to be still a few open problems. [1] However, I would bet all my money and more, that Musk,

by FrojoS 15y ago

Moon landing with humans has been done before but on Mars there seem to be still a few open problems. [1] However, I would bet all my money and more, that Musk, SpaceX and co. will get the job done within two decades if not a lot sooner. [1] This was posted on HN before by joey http://www.universetoday.com/7024/the-mars-landing-approach-getting-large-payloads-to-the-surface-of-the-red-planet/ http://www.universetoday.com/7024/the-mars-landing-approach-... http://news.ycombinator.com/item?id=2479053 http://news.ycombinator.com/item?id=2479053

rbanffy 15y ago
I would recommend a Moon landing and a permanent base before we attempt to go for Mars.
- hugh3 15y ago
  I used to be in two minds about this, but now I think I agree with you. Let's solve the problem of building a semi-self-sufficient colony on the rock in our own backyard before we try to solve the same problem on a rock a thousand times further away. All progress in space exploration has been made with baby steps. We flew men around the backside of the Moon three times before actually attempting a landing. Apollo 10 took a lunar lander within 40,000 feet of the lunar surface without landing. Whatever problems are going to arise with a Mars base I think it'd be better to solve 'em with a Moon base first. Apart from anything else it's easy to get home from the Moon if you need to evacuate, whereas easy transfers from Mars to Earth only crop up every eighteen months or so. Oh, and if you're not aware there's already a SpaceX flight to the Moon scheduled for 2013; one of the teams for the Lunar X-Prize (Astrobotic Technology) has booked one up.
  - rbanffy 15y ago
    > Oh, and if you're not aware there's already a SpaceX flight to the Moon scheduled for 2013 Wow! That's really cool. What kind of mass can SpaceX put on the lunar surface? Anyone cares to do the math?
    - hugh3 15y ago
      Luckily SpaceX has already done it for us. A Falcon 9 can supposedly put three tons on the Moon, or two tons on Mars: http://www.aviationweek.com/aw/generic/story_generic.jsp?channel=space&id=news/asd/2011/02/08/01.xml&headline=SpaceX%20Lands%20Contract%20To%20Fly%20To%20Moon http://www.aviationweek.com/aw/generic/story_generic.jsp?cha... Not sure if that includes the fuel you'll need for a soft landing, though. For comparison, an Apollo lunar lander was fifteen tons including fuel. I'm guessing a Falcon 9 Heavy could manage that.
      - rbanffy 15y ago
        A Falcon 9 can put 9900 Kg on LEO. A 9 heavy can put 5 times as much. It's reasonable to extrapolate that to about 15 tons on lunar surface or 10 on Mars. As for Mars, you can use the atmosphere to shed some speed. You can't do the same on the Moon, but your speed will be lower, so, it may as well end up being the same.
  - InclinedPlane 15y ago
    I'm not sure I agree. The technologies and expertise needed for a Mars mission are not necessarily the same as needed for a lunar colony. And the difficulty of setting up a Martian colony may actually end up being less than setting up a lunar colony (due to the ability to heavily use local resources on Mars, such as for generating fuel).
    - hugh3 15y ago
      And the difficulty of setting up a Martian colony may actually end up being less than setting up a lunar colony (due to the ability to heavily use local resources on Mars, such as for generating fuel). There's a few ways in which Mars is an easier problem than the Moon, including fewer worries about micrometeorites. As far as fuel goes, though, if you can find a good supply of water on the moon then you can start fuelling your hydrogen-oxygen rockets, no worries. edit: Others have suggested making rocket fuel out of aluminium oxide if you can't find enough water: http://www.asi.org/adb/06/09/03/02/095/al-o-propellants.html http://www.asi.org/adb/06/09/03/02/095/al-o-propellants.html
      - InclinedPlane 15y ago
        You can land an automated vehicle on the surface of Mars with a small stock of Hydrogen and brew Methane/O2 fuel (an excellent rocket fuel with an existing infrastructure of components that use it) out of the atmosphere, without having to dig or mine or anything of the sort. Moreover, Mars has a much larger quantity of much more widely distributed water ice supplies, making it far easier to bootstrap a mostly indigenous propellant, water, and Oxygen production infrastructure. As far as cracking rocks to make Oxygen, that's such an expensive proposition in capital equipment and energy requirements that it's not on the table in terms of resources that will help bootstrap exploration and colonization or that will sustain a mostly self-sufficient local industry.
mturmon 15y ago
Thanks so much for that link. I had been looking for a succinct article that explains the physical constraints on a Mars landing (for equipment only, say). It's safe to say nobody knows more about that problem than Rob Manning. The node in the discussion you refer to is: http://news.ycombinator.com/item?id=2479398 http://news.ycombinator.com/item?id=2479398 As with most threads on this subject, commenters not reading TFA believe that the retro rocket solution is straightforward. TFA explains why it's not.

by FrojoS 15y ago

rbanffy 15y ago

I would recommend a Moon landing and a permanent base before we attempt to go for Mars.

hugh3 15y ago
I used to be in two minds about this, but now I think I agree with you. Let's solve the problem of building a semi-self-sufficient colony on the rock in our own backyard before we try to solve the same problem on a rock a thousand times further away. All progress in space exploration has been made with baby steps. We flew men around the backside of the Moon three times before actually attempting a landing. Apollo 10 took a lunar lander within 40,000 feet of the lunar surface without landing. Whatever problems are going to arise with a Mars base I think it'd be better to solve 'em with a Moon base first. Apart from anything else it's easy to get home from the Moon if you need to evacuate, whereas easy transfers from Mars to Earth only crop up every eighteen months or so. Oh, and if you're not aware there's already a SpaceX flight to the Moon scheduled for 2013; one of the teams for the Lunar X-Prize (Astrobotic Technology) has booked one up.
- rbanffy 15y ago
  > Oh, and if you're not aware there's already a SpaceX flight to the Moon scheduled for 2013 Wow! That's really cool. What kind of mass can SpaceX put on the lunar surface? Anyone cares to do the math?
  - hugh3 15y ago
    Luckily SpaceX has already done it for us. A Falcon 9 can supposedly put three tons on the Moon, or two tons on Mars: http://www.aviationweek.com/aw/generic/story_generic.jsp?channel=space&id=news/asd/2011/02/08/01.xml&headline=SpaceX%20Lands%20Contract%20To%20Fly%20To%20Moon http://www.aviationweek.com/aw/generic/story_generic.jsp?cha... Not sure if that includes the fuel you'll need for a soft landing, though. For comparison, an Apollo lunar lander was fifteen tons including fuel. I'm guessing a Falcon 9 Heavy could manage that.
    - rbanffy 15y ago
      A Falcon 9 can put 9900 Kg on LEO. A 9 heavy can put 5 times as much. It's reasonable to extrapolate that to about 15 tons on lunar surface or 10 on Mars. As for Mars, you can use the atmosphere to shed some speed. You can't do the same on the Moon, but your speed will be lower, so, it may as well end up being the same.
- InclinedPlane 15y ago
  I'm not sure I agree. The technologies and expertise needed for a Mars mission are not necessarily the same as needed for a lunar colony. And the difficulty of setting up a Martian colony may actually end up being less than setting up a lunar colony (due to the ability to heavily use local resources on Mars, such as for generating fuel).
  - hugh3 15y ago
    And the difficulty of setting up a Martian colony may actually end up being less than setting up a lunar colony (due to the ability to heavily use local resources on Mars, such as for generating fuel). There's a few ways in which Mars is an easier problem than the Moon, including fewer worries about micrometeorites. As far as fuel goes, though, if you can find a good supply of water on the moon then you can start fuelling your hydrogen-oxygen rockets, no worries. edit: Others have suggested making rocket fuel out of aluminium oxide if you can't find enough water: http://www.asi.org/adb/06/09/03/02/095/al-o-propellants.html http://www.asi.org/adb/06/09/03/02/095/al-o-propellants.html
    - InclinedPlane 15y ago
      You can land an automated vehicle on the surface of Mars with a small stock of Hydrogen and brew Methane/O2 fuel (an excellent rocket fuel with an existing infrastructure of components that use it) out of the atmosphere, without having to dig or mine or anything of the sort. Moreover, Mars has a much larger quantity of much more widely distributed water ice supplies, making it far easier to bootstrap a mostly indigenous propellant, water, and Oxygen production infrastructure. As far as cracking rocks to make Oxygen, that's such an expensive proposition in capital equipment and energy requirements that it's not on the table in terms of resources that will help bootstrap exploration and colonization or that will sustain a mostly self-sufficient local industry.

mturmon 15y ago

Thanks so much for that link. I had been looking for a succinct article that explains the physical constraints on a Mars landing (for equipment only, say). It's safe to say nobody knows more about that problem than Rob Manning. The node in the discussion you refer to is: http://news.ycombinator.com/item?id=2479398 http://news.ycombinator.com/item?id=2479398 As with most threads on this subject, commenters not reading TFA believe that the retro rocket solution is straightforward. TFA explains why it's not.