NASA NICER Mission Probes Newly Discovered Black Hole
NASA is conducting a study of a newly discovered black hole called MAXI J1820+070 or J1820 for short. The investigation is being conducted using the Neutron star Interior Composition Explorer or NICER payload that is on the ISS. NICER was able to detect X-ray emissions from J1820 as it swallowed up material from its companion star.
The waves of X-rays formed what NASA calls "light echoes" that reflected off swirling gas near the black hole. The light revealed changes in the environment's size and shape. The investigation allowed scientists to measure light echoes closer to a stellar-mass black hole than ever before.
Before J1820, light echoes off an inner accretion disk were only seen in supermassive black holes that are millions to billions of solar masses. Those much larger black holes change slowly. Stellar-mass black holes like J1820 evolve much faster allowing changes to be viewed on human timescales.
NASA says that J1820 is about 10,000 light-years away from Earth toward the constellation Leo. The distance measurement is thanks to the ESA Gaia mission that provided data allowing the estimation of the distance the J1820's companion star.
One of the most exciting parts is that J1820 was completely unknown to astronomers until March 11, 2018, when an X-ray outburst was spotted making it one of the brightest sources of X-rays in the sky for a few days. NASA scientists say that while NICER was designed to find neutron stars, it has proven to be useful at studying very X-ray bright stellar-mass black holes.