NASA's Next Mission: Send Astronauts To Asteroid

yes, it is. there's a shell of primordial material surroundin­g the solar system, as does the Oort cloud, which is all cometary material. most of the asteroids we know come from the ecliptic (the plane of the earth's orbit), but a stranger is likely to come at us from any angle. while we don'rt have anything that can destroy one coming at us, we can at least try to alter the orbit so that it misses. it wouldn't take much to knock out a city, y'now.



check the Tunguska airburst of June 30, 1908, and the Chicago/Pe­shtigo fires of October 8, 1871. both were caused by cometary material exploding in the air, just above the ground. in Chcago's case, there were wildfires that night in several states, and the town of Peshtigo was virtually wiped out. the Chicago fire chief said there were numerous separate fires throughout the city.



another reason is resources: a relatively modest nickel-iro­n mass, maybe 5 miles across, might contain as much iron as used throughout human history. carbon, hydrogen, oxygen and nitrogen can be found in others; they can be mined for use either for lunar colonies or orbiting stations. they can be moved to earth or lunar orbit for the actual mining. this would be good training for catching cometary material that can be mined for freshwater and chemicals.
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