Large Binocular Telescope | University of Western Ontario | Athabasca University | 2017 Mar 29
In the March 30 2017 issue of the journal Nature, astronomers reveal that an as-yet-unnamed rare asteroid with the provisional designation 2015 BZ509 (nicknamed 'BZ') travelling in the opposite direction to all the planets and 99.99% of the other asteroids in our Solar System — a state referred to as retrograde motion— is also safely sharing the orbital space of the giant planet Jupiter.
There are about 6000 other asteroids which share Jupiter's orbit space with it. Called the 'Trojan asteroids', they co-exist easily with the giant Jupiter because they go around in the same direction, called prograde motion. If the Solar System were a giant race track around the Sun, the planets would be like monster trucks, and the asteroids like ridiculously tiny clown cars. Though all this traffic is inherently dangerous, collisions are usually avoided because the planets and asteroids go around the track in the same direction. ...
A retrograde co-orbital asteroid of Jupiter - Paul Wiegert, Martin Connors, Christian Veillet