This is 3C273. It changed our thinking about the universe.

March 16, 2013 is the 50th anniversary of the revelation that quasars are both very distant and very luminous – and therefore must be exceedingly powerful.

X-ray image of the quasar known as 3C273 and its jet. Today, this quasar is known to lie at the center of a giant elliptical galaxy. It’s thought to have a supermassive black hole at its core, the source of its vast energy output. Image via Chandra X-ray Observatory.

In visible light, 3C273 is the brightest quasar in our sky. Its name signifies that it was the 273rd object of the 1959 Third Cambridge Catalog of Radio Sources (3C). Exactly 50 years ago – on March 16 1963 – astronomer Maarten Schmidt of Caltech had a revelation about the nature of 3C273 that changed the way people think about the universe.

Read the amazing story of Maarten Schmidt and quasar 3C273 here.

Deborah Byrd