Earth Usually Has More than One Moon, Study Suggests

SPACE.com Staff

Date: 04 April 2012 Time: 07:00 AM ET

"Earthrise" seen by the Apollo 8 astronauts in December 1968. CREDIT: NASA.

Earth usually has more than one moon at any given time, according to the results of a new computer simulation.
The huge, bright and iconic moon so beloved by poets and romantics is joined by a rotating cast of captured asteroids that often measure just a few feet across. These mini-moons typically orbit Earth for less than a year before zipping back off into space, researchers said.
The scientists used a French supercomputer to simulate the movements of 10 million near-Earth asteroids as they passed by our planet. They then tracked the trajectories of the 18,000 space rocks that Earth's gravity captured in the simulation.


MORE: http://www.space.com/15151-earth-multiple-moons-asteroids.html

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