Star Shrinking

A massive star in Orion, has been shrinking for the past 15 years and astronomers do not know why.The star is a red super giant and named Betelgeuse. When massive stars are nearing the end of their lives, they swell to 100 times their original size before they explode as supernova or collapse to form black holes. The star's brightness has not dimmed over the past years. The study of the red supergaint is important to understanding of space because astronomers are not clear over how red supergaints end their lives.