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

Gstestso
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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.

userLTK
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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).

James Screech
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