The mystery of a star that seemed too small to exist has been solved – by the detection of another star hiding in the same system.
In 2019, astronomers announced the discovery of an unusual system called KIC 8145411 in which a white dwarf – the dull, compact remnant left behind after certain stars exhaust their nuclear fuel – was orbiting a sun-like star every 450 days. The system is a rare example of a self-lensing binary, where the gravitational heft of the compact white…