Captured Stars

A new study using computer simulations suggests many of the stars in the halo of our galaxy were in fact captured from other galaxies-- meaning some stars in the Milky Way are in fact older than the Milky Way.

The Milky Way is a spiral galaxy. That means huge spiral arms filled with stars and planets, gas and dust, revolve in a plane around a central bulge. At the heart of that bulge, as perhaps in most galaxies, sits a huge black hole. The halo consists of those stars above and below the plane of the spiral arms that nonetheless orbit the center of the galaxy.