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NASA Planning Mission To 40-Meter-Wide Asteroid

FudRucker points out a story from The Guardian about NASA's plans to visit 2000SG344, an asteroid 40 meters wide and weighing roughly 71 million kilograms. The manned mission would take three to six months, and it would make use of the Orion spacecraft, which will be replacing to retiring space shuttle fleet. "A report seen by the Guardian notes that by sending astronauts on a three-month journey to the hurtling asteroid, scientists believe they would learn more about the psychological effects of long-term missions and the risks of working in deep space, and it would allow astronauts to test kits to convert subsurface ice into drinking water, breathable oxygen and even hydrogen to top up rocket fuel. All of which would be invaluable before embarking on a two-year expedition to Mars. As well as giving space officials a taste of more complex missions, samples taken from the rock could help scientists understand more about the birth of the solar system and how best to defend against asteroids that veer into Earth's path."

7 of 205 comments (clear)

  1. Land, schmand. Pull it into orbit! by ThreeGigs · · Score: 4, Interesting

    Okay, so it's really really big. But not "too" big. And it just happens to be in an orbit that's very close to earth's orbit around the sun. So I'm guessing that with the right nudges at the right times, it'd be possible to swing that rock around the moon and park it in orbit around the earth. And having a million tons of raw material in orbit is something that both makes more sense than a manned landing, and is a lot more interesting and exciting, to me at least.

    1. Re:Land, schmand. Pull it into orbit! by evanbd · · Score: 5, Interesting

      It's got 1.37 km/s hyperbolic excess velocity, and on an orbit that damn near intersects ours. That means it takes a little more than 1370 m/s of delta-v to perform the capture. At 7.1E7 kg, that's about 6.6E13 joules -- approximately 15kt TNT equivalent worth of energy.

      Assuming a high performance LOX/Methane engine, it would need about 34kt of propellant (rockets are inefficient for delta-v low relative to exhaust velocity). Note that this is a significant proportion of the asteroid mass. To make it economical, you'd need something more exotic -- a mass drive throwing bits of asteroid, or a high performance solar-electric ion drive, for example.

    2. Re:Land, schmand. Pull it into orbit! by afaik_ianal · · Score: 4, Interesting

      The actual object is only 71,000 tonnes, not 1.1 million tonnes as claimed by TFA.

      The energy of any possible collision with Earth is "1.1 million tons of TNT", which is about 4.6 petajoules. I expect the energy required to pull it into orbit would be in that order of magnitude, as you'd basically be trying to slow the thing down as it got near us.

      I'm not sure how you many nukes it would take to apply that much kinetic energy to an object in space, but the biggest nukes can release in the order of 2 petajoules of heat.

      I'm not sure that I'd want an object that size -- without any means of correcting its orbit -- hovering over my house though.

  2. Finally! by Erpo · · Score: 4, Interesting

    Unmanned missions may be cheaper and safer, but sending out real people to expand the horizons of human activity in space is much more important. It gets people excited! That brings in money and inspires young people.

    Then, when NASA has a huge group of talented experts and tons of cash, they can do real science instead of worrying every day about whether the budget will get slashed before they can complete the current round of experiments.

    1. Re:Finally! by 2short · · Score: 5, Interesting

      "Think of all the money they could have saved if they sent a few robots up there."

      They could have sent thousands of robots.

      We've got two rovers operating on Mars for years for a fraction of the price it costs to send one human to the IIS in low Earth orbit. There's no question the robots get you more science for your buck, all the humans cling to is that they are better PR, but I wonder if that's true anymore? Here's a test: Without looking it up, think of the names of those rovers on Mars. Now think of the names of the current ISS inhabitants. You're paying hundreds of times as much for every day the ISS inhabitant is there.

  3. Re:Paper studies do not a mission make by MichaelSmith · · Score: 5, Interesting

    It would be awesome, don't get me wrong.. I actually think this is The Way To Go [TM] and I'm surprised to even see this being studied but NASA is not planning to send a manned mission to an asteroid, not now, not in 20 years time.. maybe *after* Mars is done but as I doubt NASA will have anything to do with that, I'm thinking they won't have anything to do with going to an asteroid either. Plans were made to do it with Apollo, in the 1970's but then the Shuttle came along and the US confined themselves to low earth orbit.

    Their new capsule design is basically Apollo again so the old plans are on the table. An asteroid mission is a stepping stone to missions to the planets. It is shorter, but interesting all the same.

    The asteroids are a likely resource for Earth. Planets are only of use to us for colonisation or science. There is no way to export from Mars to Earth for example, but water could be exported from asteroids to the moon.

    This is a great idea. I can't wait to watch.
  4. Re:Planned mission != actual mission by MBGMorden · · Score: 4, Interesting

    http://en.wikipedia.org/wiki/Mars_Direct

    This is proposed back in 1990, and was deemed to be a viable plan for going forward with technology we had at that time. As with all missions, we don't know the SPECIFICS (as in, we don't have blueprints of the craft to take us), but if we had those we'd probably already be on the way there now. There are enough sound plans out there that I'm sure if funding were approved for the mission, we'd be able to do it. The problem though, is not in solving problems, getting a clear roadmap, or whatnot. The problem is in getting the government to simply lay down the funding so we can go.

    --
    "People who think they know everything are very annoying to those of us who do."-Mark Twain