Comet Lovejoy is a long period (~10,000 year) comet. In 2015 it passed about 1.3 AU from the Sun. It outgased a large amount of organic material the fluoresced strongly from the Sun's UV radiation, giving it a beautiful blue-green glow. It was just bright enough to be seen with the naked eye by an experienced observer under good conditions. It was an easy object with binoculars or a small telescope.

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