1
$\begingroup$

As we know, rogue planets don't orbit around a star, how about galaxy? Can a rouge planet not orbit around a galaxy?

$\endgroup$

2 Answers 2

3
$\begingroup$

They would be enormously difficult to observe, but with a big enough gravitational assist a rogue planet certainly could be ejected from a galaxy and become a "double rogue" so to speak, or intergalactic rogue planet is probably a better term. Rogue (or intergalactic) stars have been observed. Here and Here. The same gravitational forces that create intergalactic stars absolutely should create inter-galactic rogue planets and in fairly significant numbers. The merging of 2 galaxies should create millions of them.

$\endgroup$
3
$\begingroup$

There is no reason why it couldn't, though the chances of it happening are small. There are hyper velocity stars that are not gravitationally bound to the Milkyway, if a planet is ripped away from its star due to a close encounter with another star or black hole it could be given enough velocity to reach a galaxies escape velocity (about 537 km/s).

$\endgroup$

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .