The speediest stars in the galaxy, moving at hundreds or even thousands of kilometres per second, are also some of the least well-studied. A study of 15 of these fast-moving objects has found that most of them probably came from dwarf galaxies devoured by the Milky Way in the distant past.
“Some stars that are travelling fast have been [proposed to have] an extragalactic origin, but this is the first time that a relatively large sample has been analysed and evidence has been shown that they …