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Not only is it essential for the defense of our planet, but it will be very important economically. Being able to capture asteroids within the moon's orbit to b

• jojobas 3y ago
  I'd say it's a far cry. Nudging an asteroid at 10m/s a couple of months out might be enough to miss the Earth, to capture it in a lunar orbit you need two orders of magnitude more at the very least.
  • pavel_lishin 3y ago
    Couldn't you play some games with orbital mechanics, and use the Earth-Moon system to capture the asteroid as it goes by? You don't have to expend all the delta-v to move it into an Earth or Moon orbit - you just have to put enough there to aim it at one spot, and let gravity do the rest.
    • jojobas 3y ago
      That's not how it works. You may save some energy by gravity assists, but you're not getting a factor of even 10.
    • lolc 3y ago
      We want the damn things to pass by. If we try to capture them we have to maneuver their trajectory very very close! I have no idea of astrophysics but due to their high speed the distance where they'd be in orbit would likely be below the surface of the earth! The orbital speed at the earth's surface is only 7.9 km/s[1] which is rather slow for an asteroid this close to the sun. Even if we found a favorable candidate it'd still be the difference between shooting at a mortar shell to change the direction away from you to avoid the shell hitting you, and shooting at the shell to get the shell to pass close to you. The later action has a much worse risk profile. [1] https://en.wikipedia.org/wiki/Orbital_speed https://en.wikipedia.org/wiki/Orbital_speed