If a star with a large peculiar proper motion and/or speed with respect a typical disk star is found what other property would you expect it to have?

Question

Quizplus · Accepted Answer

A star with a large peculiar proper motion and/or speed with respect to a typical disk star is likely to be a halo star, which means it is old, has a low luminosity, and has poor metal content compared to the Sun. Therefore, all of the given choices are expected properties for such a star. A large peculiar proper motion and/or speed with respect to a typical disk star indicates that the star has a different origin than most of the stars in its vicinity. This suggests that it is likely to have formed in a different environment or at a different time compared to other stars. Therefore, it is reasonable to expect that such a star would have low luminosity, poor metal content compared to the Sun, and be old. Thus, option D (all of the above) is the correct answer.

If a Star with a Large Peculiar Proper Motion And/or