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65803 Didymos
Encyclopedia
65803 Didymos is an Apollo asteroid
discovered on April 11, 1996 by Spacewatch
at Kitt Peak
. It has a satellite orbiting it with a period of 11.9 hours, hence the appellation "Didymos", meaning "twin". The primary asteroid is about 800m in diameter, the satellite is about 150m in diameter in an orbit about 1.1 km from the primary. The rotation rate of Didymos is fast, 2.26 hours. Its density is 1.7 +/-0.4 g/cc. Didymos is the most easily reachable asteroid of its size from Earth, requiring a delta-v
of only 5.1 km/s for a spacecraft to rendezvous compared to 6.0 km/s to reach Earth's moon.
Apollo asteroid
The Apollo asteroids are a group of near-Earth asteroids named after 1862 Apollo, the first asteroid of this group to be discovered by Karl Wilhelm Reinmuth...
discovered on April 11, 1996 by Spacewatch
Spacewatch
Spacewatch is a project at the University of Arizona led by Robert S. McMillan that specializes in the study of minor planets, including various types of asteroids and comets...
at Kitt Peak
Kitt Peak
Kitt Peak is a mountain in the U.S. state of Arizona. It is the location of the Kitt Peak National Observatory. The radio telescope at the Observatory is one of ten dishes comprising the Very Long Baseline Array ....
. It has a satellite orbiting it with a period of 11.9 hours, hence the appellation "Didymos", meaning "twin". The primary asteroid is about 800m in diameter, the satellite is about 150m in diameter in an orbit about 1.1 km from the primary. The rotation rate of Didymos is fast, 2.26 hours. Its density is 1.7 +/-0.4 g/cc. Didymos is the most easily reachable asteroid of its size from Earth, requiring a delta-v
Delta-v
In astrodynamics a Δv or delta-v is a scalar which takes units of speed. It is a measure of the amount of "effort" that is needed to change from one trajectory to another by making an orbital maneuver....
of only 5.1 km/s for a spacecraft to rendezvous compared to 6.0 km/s to reach Earth's moon.