NICER / ISS Science Nugget for May 17, 2019

Record-low flux reported for black-hole binary GRS 1915+105

GRS 1915+105 is a black hole binary system which was discovered 27 years ago and has been bright and variable ever since. Over this time, GRS 1915+105 has exhibited a unique repertoire of variability cycles and impulsive jets that have provided new insight into black hole systems. NICER has been regularly monitoring this source and has found that over the past 10 months it has been steadily declining in flux.

NICER recently found a very sharp decline in its intensity just in the past week (see figure below) that represents the lowest flux ever observed from this exciting black hole system.

This discovery was reported in Astronomer's Telegram #12742 on May 10^th by Homan et al.