送交者: steven 于 2005-5-04, 19:50:38:
回答: It gets interesting. I appreciate your insights. 由 cornbug 于 2005-5-04, 19:43:57:
object in parabolic trajectory never comes back, it is called the escape orbit. Cicular or elliptic orbits are called capture orbit. Of course, these are under the condition called the standard assumption.