A Question about extragalactic stellar motion

AI Thread Summary
The discussion focuses on the motion of extragalactic stars near the Milky Way, particularly those on hyperbolic transits. Participants note that most identified extragalactic stars are associated with other galaxies, making it difficult to find examples fitting the proposed model. Concerns are raised about the accuracy of distance measurements for stars within two galactic radii, as these can significantly affect motion analysis. It is highlighted that hypervelocity stars are primarily ejected from the Milky Way, with extragalactic stars arriving from other galaxies being exceedingly rare. The potential increase in such stars will occur during the future merger of the Milky Way and Andromeda.
Prez Cannady
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Looking for a model--any model but one in particular--of extragalactic stellar motion.
We have direct mass models of stellar motion inside of galaxies (basically, find a happy medium between a sphere and a disc). And of course dark matter corrections to explain the deviation between model and observation.

Is there any pattern at all to the motion of extragalactic stars passing within one or two galactic radii of Milky Way on hyperbolic transits?
 
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Prez Cannady said:
Summary:: Looking for a model--any model but one in particular--of extragalactic stellar motion.

Is there any pattern at all to the motion of extragalactic stars passing within one or two galactic radii of Milky Way on hyperbolic transits?

couldnt even find any extragalactic stars that fit your idea. I went through a large list of specific extragalactic ( to the Milky Way) stars
and all but 1 or 2 were associated with other galaxies

So, what stars did you have in mind ?
 
I have not heard of any reason to believe they deviate from Newton or Einstein.

The distance to stars is usually listed with an error range. If the star in question is 2 galactic radii away from us distance measurements are very suspicious. A single star's motion can be caused but a wide variety of factors.

Most hypervelocity stars were ejected from the Milky Way. Extragalactic stars that were ejected from some other galaxy but did arrive here are going to be extremely rare. In a few billion years when Milky Way and Andromeda are about to merge they will temporarily become more common.
 
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