Hanny's Voorwerp (Hanny's object in Dutch)

Hanny's Voorwerp is named after its discoverer Hanny van Arkel who, in 2007, was participating in the Galaxy Zoo project when she noticed the Voorwerp--a supergiant cloud of glowing green gas--but couldn't classify it, and so brought it to the attention of the Galaxy Zoo forum. There it caught the attention of other Galaxy Zoo volunteers, the Galaxy Zoo team and eventually professional astronomers.

Credit: NASA, ESA, William Keel (University of Alabama, Tuscaloosa), and the Galaxy Zoo team



This diagram explains the formation of the strange green object known as Hanny’s Voorwerp. Astronomers believe that it is part of the long streamer of gas that extends from galaxy IC 2497, lit up brightly by the searchlight beam of a recently extinguished quasar. Credit: NASA, ESA