"The giant red star Betelguese - the red star in the shoulder of the constellation Orion - is 700 million miles across, about 800 times larger than the Sun. Light takes 1 hour to travel from one side of the giant star to the other. The name of this star means "The Armpit of the Central One" in Arabic, which shows that like many other constellations, Orion was recognized across many cultures."
My favorite constellation is Orion, by the way. It has always fascinated me for some reason, and I have gazed up at it many many times wondering and wondering.
Ever wondered how to pronounce it? This is how: Be·tel·geuse (btl-jz, btl-jz).
"A star's primary source of energy, during its lifetime, is the fusion of hydrogen occurring in its core. As the hydrogen is used up, the helium which is produced fills up the core. But the temperature is not high enough for helium fusion to occur, so core energy production slows down, its outward pressure decreases, and the gravitational forces cause the core to contract. As the core contracts the atoms bunch closer together causing an increase in density and temperature. When the core temperature is high enough, helium fusion begins. At the same time as the helium core is contracting and heating up, an outer hydrogen shell expands and begins fusing to form more helium. It is this expansion and fusion reaction in the hydrogen shell which pushes the star's envelope out into space. The surface of the now giant star is so far away from the hot core that it cools down and turns red (hence the name red giant)."
Betelgeuse is also known as:
Other scientific data about Betelgeuse:
Betelgeuse is the 12th brightest star in the sky. It is called Alpha Orionis even though it is fainter than Beta Orionis (Rigel). This is because Betelgeuse, a variable star, was misclassified.