Six Minutes and Counting

Inter-University Centre for Astronomy and Astrophysics Artistic impression of the double white dwarf binary eRASSU J0608. Current gravitational wave observatories aren’t sensitive enough to capture the gravitational waves of binary stars. They can only see the gravitational chirps of black holes just as they are merging. But that will change as we develop more sensitive instruments. Recently a team of astronomers has discovered a binary white dwarf system that could be a good target for advanced gravitational observatories.1 The system is known as eRASSU J0608. It’s an x-ray source that has a bright pulse every 374 seconds, or just over six minutes. Usually when we observe a repeating source such as this, it is due to some kind of periodic motion. Pulsars are due to the rotation of a neutron star. Many variable stars are eclipsing binaries. So the team wanted to see what was behind eRASSU J0608. Using data from the Neutron star Interior Composition Explorer (NICER) and the Einstein…