Trapezium C1 main sequence star. Animation of the location in the night sky and the properties of the blue O-type star Trapezium Cluster C1 (Theta1 Orionis C1), 1340 light years from Earth in the constellation of Orion. Trapezium Cluster star C1 is a main sequence star, 10.6 times the width of the Sun (over 14 million kilometres across) and 33 times the Sun's mass. Theta1 Orionis C1 is part of the Trapezium open star cluster, and is part of a binary star system with a massive companion (Theta1 Orionis C2). Both stars have a powerful stellar wind and emission of ultraviolet light, and are responsible for much of the glow that illuminates the Orion Nebula. The stars are less than a million years old and will explode in a supernova in a few million years. Trapezium Cluster star C1 is spectral type O6, with a luminosity class of Vp. It has a luminosity 204, 000 times that of the Sun, and has an atmospheric temperature of 39, 000 Kelvin. Its spectrum has ionised helium lines and a prominent ultraviolet continuum.