NGC 281, also known as the PacMan Nebula, is an emission nebula in the constellation Cassiopeiae, which is an active region of star formation. The stars of the young open cluster IC 1590, which is embedded in the nebula, provide the radiation that keeps NGC 281 ionized. The most important contributor of ionizing radiation is the binary star HD 5005 (the bright star seen at the heart of the nebula), the primary of which is a massive O star (visual magnitude 7.8). Dark lanes of dust are likely areas of future star formation, while multiple dark Bok globules are places in which stars are presently in the process of being formed.