C/2014 Q2 (Lovejoy) is a long-period comet discovered on 17 August 2014 by Terry Lovejoy. This photograph was taken from Tucson, Arizona, using a Sky-Watcher 100mm APO telescope and SBIG STL-11000M camera. (JOHN VERMETTE / WIKIMEDIA COMMONS)

This Is Why Comets Glow An Eerie Green Color

The ices and rock aren’t green, and neither are the tails. So where does a comet’s green color come from?

Every so often, with extreme regularity, comets will plunge from beyond the orbit of Neptune into the inner Solar System. From well beyond the orbit of Saturn, they remain cold, frozen, and in a dormant state…