Astronomers studying observations taken by NASA’s Wide-field Infrared Survey Explorer (WISE) mission have discovered the first known “Trojan” asteroid orbiting the sun along with Earth.
Trojans are asteroids that share an orbit with a planet near stable points in front of or behind the planet.
2010 TK7@wiki: http://en.wikipedia.org/wiki/2010_TK7
2010 TK7 is the first Trojan asteroid discovered sharing the Earth’s orbit in the Earth-Moon system around the sun. Trojan satellites are theoretically predicted objects which orbit 60° ahead of or behind a planet in its orbit, and which had previously only been observed in the orbits of Mars, Jupiter and Neptune.
2010 TK7 has a diameter of about 300 metres (1,000 ft). Its path oscillates around the Sun-Earth L4, shuttling between this and the L3 Lagrangian point with a period of about 400 years.
More:
http://www.jpl.nasa.gov/news/news.cfm?release=2011-230
http://www.nasa.gov/multimedia/videogallery/index.html?media_id=103550791
Flaskpost.com 