It seems that astronomers are now able to detect dim galaxies (as in not very visible, not as in "stupid") that are in front of very bright quasars.
To locate the so-called "invisible" galaxies, Bouche and his team looked through huge catalogues of quasar data and picked out those with "dips" in their light signatures. Then, using the European Southern Observatory's (ESO) Very Large Telescope (VLT), located in the mountains of northern Chile, the team searched for galaxies close to the pulse of quasar light.
The astronomers capitalized on the VLT's special infrared spectrometer, called SINFONI, to pick apart 20 patches of sky around the quasars to search for galaxies from the time when the universe was about 6 billion years old, almost half its current age. Seventy percent of the time, they found a galaxy hiding in the "headlights" of a quasar.