Observatories & Telescopes

Nobody has ever watched a black hole's jet move. The plasma thrown out of the quasar 3C 345, in the constellation Hercules, has been under observation for half a century, but always as stills, an…

A comet is, in the most literal sense, a piece of frozen memory. The ice that makes up its body records the temperature, the chemistry, and the company it kept when it first congealed out of a cloud…