关于Trojan asteroid的一点背景

eric_guoyi

Trojan asteroid：

As originally defined, Trojan asteroids have a semi-major axis between 5.05 AU and 5.40 AU, and lie in elongated, curved regions around the two Lagrangian points 60° ahead and behind of Jupiter. The term is sometimes used to refer to minor bodies with similar relationships to other major bodies.

Trojan asteroids may also have played a key role in the formation of the Moon, for which the leading theory states that it formed from the debris of a collision between Earth and a Mars-sized planet very early in the history of the Solar system. Because the collision must have hit Earth sideways and not too hard (otherwise it would have led to full destruction of both objects), it is believed that this hypothetical planet, dubbed Theia, formed from planetesimals that settled into the Lagrangian point L₄ of the Sun-Earth system before some cause sent the body veering out of its orbit slowly, onto a path of eventual collision with the young Earth.

cpcjustin

thank you very much!

greenbow43

太专业了吧

我一个头两个大，有没有汉语说明阿