Image of the region of the space occupied by the rare quasar quartet. The four quasars are indicated by arrows. Credit: Hennawi & Arrigoni-Battaia, MPIA
Image of the region of the space occupied by the rare quasar quartet. The four quasars are indicated by arrows. The quasars are embedded in a giant nebula of cool dense gas visible in the image as a blue haze. The nebula has an extent of one million light-years across, and these objects are so distant that their light has taken nearly 10 billion years to reach telescopes on Earth. This false color image is based on observations with the Keck 10m telescope on the summit of Maunakea in Hawaii. Credit: Hennawi & Arrigoni-Battaia, MPIA