Second, the event reveals a hypothesized object called a kilonova, because it briefly
shines thousands of times brighter than an ordinary nova.
There are two different black hole scenarios proposed to explain these objects: (1) they contain very «big» black holes that could be more than a
thousand times more massive than the Sun (Note 1), or (2) they are relatively small black holes, «little monsters» with masses no more than a hundred
times that
of the Sun, that
shine at luminosities exceeding theoretical limits for standard accretion (called «supercritical (or super-Eddington) accretion,» Note 2).