When observing quasar J0742+2704, Achenbach was surprised to find it was not elliptical. "The biggest surprise was seeing the ...

However, in this case, the light has not been perfectly lensed and the ring shape is mainly due to the duplication of the ...

The tremendous amount of radiation emitted by a quasar makes it visible from billions of light ... their surroundings have been collected through Hubble’s recent close-up images of them. These ...