by Chris Peterson » Wed Jul 13, 2011 4:26 pm
60moo wrote:...or must they belong to a cluster or galaxy? Can we actually detect "hermit" stars? If so, is it inevitable that they will one day end up as part of a group? Is there a particular size below which a star tends to be isolated?
A star which is not gravitationally bound to a galaxy is usually called a rogue star or intergalactic star, and examples have been observed. These stars form as usual in galaxies but are ejected by gravitational interactions, either from binary systems or during galactic collisions. In a galaxy cluster, intergalactic stars may, in total, mass more than any individual galaxy.
There is probably no mass dependence on the likelihood of a star getting ejected from a galaxy.
[quote="60moo"]...or must they belong to a cluster or galaxy? Can we actually detect "hermit" stars? If so, is it inevitable that they will one day end up as part of a group? Is there a particular size below which a star tends to be isolated?[/quote]
A star which is not gravitationally bound to a galaxy is usually called a rogue star or intergalactic star, and examples have been observed. These stars form as usual in galaxies but are ejected by gravitational interactions, either from binary systems or during galactic collisions. In a galaxy cluster, intergalactic stars may, in total, mass more than any individual galaxy.
There is probably no mass dependence on the likelihood of a star getting ejected from a galaxy.