Is the Milky Way an ‘outlier’ galaxy? Studying its ‘siblings’ for clues

The most-studied galaxy in the universe — the Milky Way — might not be as ‘typical’ as previously thought, according to a new study. Early results from the Satellites Around Galactic Analogs (SAGA) Survey indicate that the Milky Way’s satellites are much more tranquil than other systems of comparable luminosity and environment. Many satellites of those ‘sibling’ galaxies are actively pumping out new stars, but the Milky Way’s satellites are mostly inert.