Hertzsprung-Russell Diagram Animation Using Cluster Omega Centauri In this video, the stars in globular cluster Omega Centauri are rearranged according to their intrinsic brightness (vertical axis) and their temperature (horizontal axis). The temperature of a star dictates its apparent colour, with cooler stars being red and hotter ones being blue. The majority of stars at any given time fall into a wide band known as the main sequence, which passes from the top left (hot, bright stars) to the b