Primordial stars left their imprint on dwarf galaxy

A handful of ancient stars outside the Milky Way witnessed the explosive deaths of the first generation of stars, researchers report in the April 1 Astrophysical Journal. The eyewitnesses harbor unusual amounts of heavy elements, such as magnesium and silicon, which means they were probably bystanders to a few supernovas from primordial stars up to about 20 times as massive as the sun.

The stars live about 290,000 light-years away in the puny Sculptor galaxy. Astronomers think that dwarf galaxies like Sculptor are relics from the early universe, which makes these galaxies useful laboratories for studying conditions from not too long after the Big Bang.