Hubble Space Telescope orbiting Earth, animation. The view then zooms in to an image of the remote quasar SDSS J083643.85 + 005453.3. A quasar is an energetic and distant active galactic nucleus. This quasar had its spectrum measured in 2002, in a study that detected iron in the spectra of very distant quasars. This result was important as it means the first stars in which the iron was produced were born just 200 million years after the Big Bang, much earlier than previously thought.