From Popular Science:
The U.S. Air Force has upgraded its ability to predict possible satellite collisions, as the risk from space debris increases.
Satellites currently must dodge an ever-growing gauntlet of other satellites and clouds of space debris, and this year the Pentagon has quietly upgraded its surveillance accordingly. The U.S. military announced yesterday that it now tracks 800 maneuverable satellites, compared to less than 100 prior to a February collision between an active U.S. satellite and a retired Russian communications satellite.
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