Asteroid Terrestrial-impact Last Alert System

ATLAS is an asteroid impact early warning system being developed by the University of Hawaii and funded by NASA.    When ATLAS is completed in 2017, it will consist of two telescopes, 100 miles apart, which automatically scan the whole sky several times every night looking for moving objects.  ATLAS will provide one day's warning for a 30-kiloton "town killer," a week for a 5-megaton "city killer," and three weeks for a 100-megaton "county killer".