For education and discussion only. Not for commercial use. PARIS: Earth has acquired a "quasi-moon" - an asteroid that will encircle our planet for the next couple of years, while it orbits the sun on a horseshoe-shaped path, according to a report to be published on Saturday in New Scientist . The asteroid, 2003 YN17, "is probably a chunk of debris" from an impact between a larger space rock and the surface of the moon, the British weekly said. 2003 YN17's orbital plane is roughly the same as the earth's, but its unusual path, compounded by a corkscrew-like track, means...