MOST black holes come in one of two sizes—regular and extra-super-huge.
Astronomers have long searched for an intermediate-sized black hole and now
they’ve found one. Studying this middleweight should help them understand how
the supermassive black holes at the centre of all galaxies and quasars are
formed.
Most black holes are born from a single star, but those at the hubs of
galaxies can be millions or billions of times more massive than the Sun. The new
middleweight black hole weighs in at roughly 500 solar masses.
At a press conference at NASA headquarters in Washington DC last week,…
