The Pacman nebula, 9,200 light years from Earth, is found in the Cassiopeia constellation, part of the Perseus Spiral Arm of our Milky Way. It was discovered in August 1883 by astronomer Edward Emerson Barnard and, since then, it has been imaged in a variety of new and wonderful ways as NASA has endeavoured to find out more about this stellar nursery.
NGC 281 is actually a cluster of stars found about 1,000 light years above the plane of the Milky Way. Thanks to its positioning it is not obscured by much dust or gas in X-ray and infrared images, so it gives astronomers an almost unhindered view of the star formation within. In visible light a portion of the nebula is hidden by dust and gas, forming a gap like a mouth. This led NASA to dub NGC 281 the ‘Pacman nebula’, due to its resemblance to the famous video game character.
The nebula plays host to a variety of high-mass stars, those that contain more than eight times the mass of the Sun, which are important in the universe as they pump out a lot of energy. Inside the Pacman nebula there are a large number of these stars and, thanks to the unobscured view, it is a perfect place to observe them.
Image Credit: NASA