Supergiant
Supergiants are some of the largest stars in the universe. They are larger than giant stars, and less luminous than hypergiants. They vary greatly in size. They are towards the top of the Hertzsprung–Russell diagram, a graph showing star development. Some are only 50 million kilometers across, small enough to fit inside the orbit of Mercury. The largest and brightest supergiants, also called hypergiants, are 2,200 million km across, between the sizes of the orbits of Jupiter and Saturn.