#Asteroid Forensics May Point to #Alien Space Miners

Rather than looking for aliens who use interstellar radio signals to say “hi," an alternative search strategy is simply to spy on any mega-engineering projects that an advanced civilization might be undertaking. Veteran SETI astronomer Jill Tarter calls this strategy "SETT" -- the Search for Extraterrestrial Technology.
A new science paper by Duncan Forgan at the University of Edinburgh in Scotland and Martin Elvis at the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass., suggests we look for evidence of a very ambitious macro-engineering project: the wholesale mining of an asteroid belt. The asteroid material may be mined to build space colonies, solar power satellites or maybe even an entire "ringworld," as imagined by sci-fi writer Larry Niven.
What's more, precious metals are in high demand for technologies such as computers, high-speed networks and mobile phones. So-called "green technologies" of the future, such as hydrogen fuel cells, will also place a demand on rare resources.
The unconsolidated debris from the birth of planets, asteroids provide a smorgasbord of elements and minerals for harvesting. Meteorite samples suggest that large quantities of gold, platinum, iron, nickel, magnesium and silicon, among other elements, are abundant on asteroids.

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