NGC 281 was discovered on November 16, 1881 by the American astronomer Edward Emerson Barnard. It is an emission nebula in the constellation Cassiopeia, 9,500 light years away from Earth. In addition to the designation NGC 281, the nebula is also listed under catalogue numbers LBN 616, Ced 3 and IC 11. In the Pacman Nebula is embedded the open star cluster IC 1590, whose stars are scattered around the centre of the nebula and some of them emerge through their X-rays. The brightest member of IC 1590, the multiple star system BD +55° 191 (HD 5005), is the ionizing source of the nebula. The nebula also contains several Bok globules in which infrared images have shown signs of star formation. Infrared images also show the molecular cloud, the ionized part of which is the emission nebula.