In astronomy, double planet and binary planet are informal terms used to describe a binary system where both objects are of planetary mass. Though not an official classification, the European Space Agency has referred to the Earth–Moon system as a double planet. The IAU General Assembly in August 2006 considered a proposal that Pluto and Charon be reclassified as a double planet, but the proposal was abandoned.
There are also binary asteroids (also known as double minor planets) such as 90 Antiope, and binary Kuiper belt objects (KBOs) such as 79360 Sila–Nunam and 1998 WW31.
Read more about Double Planet: Definition of A Double Planet, Double Planets in Fiction
Famous quotes containing the words double and/or planet:
“One key, one solution to the mysteries of the human condition, one solution to the old knots of fate, freedom, and foreknowledge, exists, the propounding, namely, of the double consciousness. A man must ride alternately on the horses of his private and public nature, as the equestrians in the circus throw themselves nimbly from horse to horse, or plant one foot on the back of one, and the other foot on the back of the other.”
—Ralph Waldo Emerson (1803–1882)
“Are there no Moravians in the Moon, that not a missionary has yet visited this poor pagan planet of ours, to civilize civilization and christianize Christendom?”
—Herman Melville (1819–1891)