rjs (12/16/82)
Many thanks to all who answered my question about the safe return to earth of metals mined in space. As promised, here is a summary of responses. I have not included information supplied directly to the net, just that which was mailed to me. 3 of the 5 respondants thought that bringing the metals to the earth's surface was not the most economical thing to do, and one of the others thought that only relatively rare metals such as platinum should be broght to earth. The favored alternative was to use the metals for construction in space, either of things to be used in space (space stations, etc.) or finished products to be space shuttled down to earth. Using metals mined in space to create things to be used in space is considered economical because of the large cost of boosting metal into space from the earth. If metals are to be brought to the earth, two major methods were discussed. 2 respondants suggested building a large, simple (no engine) shuttle out of some of the metal to be used to glide the rest of the metal down to earth. 2 respondants suggested melting a big glob of metal and injecting air to make it foam (or make it foam without air to create cells surrounding vacuum). The idea is to get the density down low enough that it floats on water or lower atmosphere, then drop it down to earth. The concept of foam steel (or other metal) has been discussed on the net since my submission. The following references were provided for further reading: The NASA summer studies Toward Distant Suns by T.A. Heppenheimer The Third Industrial Revolution by G. Harry Stine The Fertile Stars by Brian O'Leary I will not exist netwise till Jan 3, 1983 (vacation and all), so sending further mail to me will probably not be productive. Robert Snyder floyd!rjs