Uttley, P.Gendreau, K.Markwardt, C.Strohmayer, T. E.Bult, P.Arzoumanian, Z.Pottschmidt, KatjaRay, P. S.Remillard, R.Pasham, D.Steiner, J.Neilsen, J.Homan, J.Miller, J. M.Iwakiri, W.Fabian, A. C.NICER Team2023-08-312023-08-312018-03-15Uttley, P., K. Gendreau, C. Markwardt, T. E. Strohmayer, P. Bult, Z. Arzoumanian, K. Pottschmidt, et al. “NICER Observations of MAXI J1820+070 Suggest a Rapidly-Brightening Black Hole X-Ray Binary in the Hard State.” The Astronomer’s Telegram 11423 (March 1, 2018): 1. https://www.astronomerstelegram.org/?read=11423.http://hdl.handle.net/11603/294684 pagesen-USThis work was written as part of one of the author's official duties as an Employee of the United States Government and is therefore a work of the United States Government. In accordance with 17 U.S.C. 105, no copyright protection is available for such works under U.S. Law.Public Domain Mark 1.0http://creativecommons.org/publicdomain/mark/1.0/Text