How 2 quasars at the dawn of time could be a Rosetta stone for the early universe

This illustration depicts two quasars in the process of merging. Using both the Gemini North telescope and the Subaru Telescope, a team of astronomers have discovered a pair of merging quasars seen only 900 million years after the Big Bang. Not only is this the most distant pair of merging quasars ever found, but also the first confirmed pair found in the period of the universe known as cosmic dawn.

A double quasar spiraling toward a great merger has been discovered lighting up the "cosmic dawn," just 900 million years after the Big Bang.