#astrophysics
Remember the gravitational wave detection a few years ago that earned the scientists Noble prize?
New puzzle from that study. They calculated mass of the two black holes as 23 and 2.6 times that of Sun. The smaller one is puzzling, because as per our understanding that can't exist.
Either that has to be massive as like 5 times the mass of Sun for it being a blackhole. Else smaller like 2.5 times the mass of Sun for being the next possible body -- a Neutron star.
Bodies in between these aren't stable, explode and disappear. Check Supernova and how not all supernova turn into blackholes.
Requires a rewrite of our understanding of astro physics.
https://edition.cnn.com/2020/06/23/world/gravitational-waves-object-black-hole-scn-trnd/index.html