Anniek J. Gloudemans

In the grand hall of the cosmic masquerade, quasars are the most skilled actors. They don disguises, change their makeup, and pass themselves off as something they are not. Two such impostors caught astronomers' eyes: both claimed to be gravitationally lensed quasars in the early Universe, but scrutiny unmasked them.

In the first few hundred million years after the Big Bang, the universe was a dark ocean in which the first stars and black holes ignited. Some of those black holes shot out narrow jets of plasma traveling at nearly the speed of light. If such a jet points straight at Earth, we see it as a bright spot: a blazar.