A dead star may have munched down on an icy exomoon

By Jonathan O’Callaghan

Astronomers may have found the best evidence yet for an exomoon – a moon in another solar system – but we can’t see it directly because it was eaten by its star 3 million years ago.

Beth Klein at the University of California, Los Angeles, and her colleagues used the Keck Observatory in Hawaii to study GALEX J2339-0424, a white dwarf about 300 light years from Earth. White dwarfs are the dense remnants left behind after some stars exhaust their fuel and expand into red giants before collapsing. …