Life on a planet with a black hole sun

Abstract

An exoplanet is thought to be orbiting an X ray binary system in the M51 galaxy (Whirlpool Galaxy). An X ray binary consists of a neutron star (rarely a black hole) that accretes matter from a main sequence star. An X ray light curve was fitted to the system and there was a dip in the curve, which indicates some object is blocking the X rays. The object is Saturn sized and most likely a planet.