ctive galaxies, such as this one, are commonplace in the Universe. Quasars are an example.
Astronomers think that all active galaxies are driven by the same engine: a supermassive black hole
with the mass of at least a few million solar masses. As matter falls into the hole, the doomed
material is heated to extremely high temperatures, which is why quasars can be seen over such
gigantic distances. Some active galaxies have an additional feature: they spurt jets of gas far into
space at speeds approaching that of light.