The confirmation, based on analysis of 10 billion year-old dying RRLyrae stars in the Gemini constellation, was done by an international team of astronomers who report their findings in The Astrophysical Journal.
By analyzing measurements of 1207 RRLyrae stars taken by the Catalina Mount Lemmon Telescope in Tucson, the team was able to observe dramatic brightness variations in these stars, taking place over periods as short as half a day.