Astronomers used RR Lyrae stars to trace the early Milky Way, revealing a rapid formation of its halo and disk, with chemical patterns similar to Andromeda.
Over the course of billions of years, the universe has steadily been evolving. Thanks to the expansion of the universe, we are able to "see" back in time to watch that evolution, almost from the ...
From our point of view, stars last a very long time, generally measured in millions of years. As with anything, however, they go through cycles of creation and destruction. In the time just after the ...