A group of red giants discovered four years ago seems to be old and young at the same time. Scientists now prove that they are indeed old – and a result of star mergers.
Four years ago, several red giant stars were discovered to pose a paradox: even though they are built from very old stellar material, their large masses indicate a clearly younger age. Scientists from the Max Planck Institute for Solar System Research (Germany), Aarhus University (Denmark), and Ohio State University (USA) have now solved the apparent contradiction. For the first time, they investigated the abundances of carbon, nitrogen, and…