A sudden dimming of GRS 1915+105 in X-rays

The black hole X-ray binary GRS 1915+105 has been in outburst since its discovery in 1992 by Castro-Tirado et al. (1992, IAUC 5590). In July of 2018 Negoro et al. (ATel #11828) reported that GRS 1915+105 had entered its faintest state in soft X-rays ( We have been observing GRS 1915+105 with NICER on a weekly basis for over a year (see, e.g., Neilsen et al. 2018, ApJ, 860, L19).