MAXI J1820+070 continuing its rapid evolution toward the hard state

We report on recent NICER observations of the transient black hole candidate MAXI J1820+070 (ASASSN-18ey). After spending the initial part of its outburst in the hard state, MAXI J1820+070 made a rapid transition to a softer spectral state in early July (ATel #11820, #11823).