Science: The Mysterious Celestial Twins

A pair of distant quasars stirs astronomers

Of all the objects that astronomers have found in the skies, quasars are the most enigmatic. Though they resemble ordinary stars when viewed through optical telescopes, they are billions of lightyears* away, the farthermost objects in the observable universe. But to be seen through ordinary telescopes and detected by radio telescopes at those distances, quasars must radiate more energy than entire galaxies, which are giant islands of billions of stars. Now, while trying to explain what quasars are and how they radiate so much energy, astronomers have...

Want the full story?

Subscribe Now


Learn more about the benefits of being a TIME subscriber

If you are already a subscriber sign up — registration is free!