Portrait of NGC 281 . ... Credit Copyright: J-P Mets vainio ( Astro Anarchy ) Explanation: Look through the cosmic cloud cataloged as NGC 281 and it's almost easy to miss stars of open cluster IC 1590 . But, formed within the nebula , that cluster's young, massive stars ultimately power the pervasive nebular glow . ... Playfully called the Pacman Nebula because of its overall shape, NGC 281 is about 10,000 light-years away in the constellation Cassiopeia . ... NASA Official: Jay Norris. ...