AS102 Study Guide - Midterm Guide: Red Supergiant Star
Document Summary
On the h-r diagram the life track zigzags across the top of the diagram as the star contracts and balloons out during each cycle. In the most massive stars the star progresses to a red supergiant like betelgeuse in orion with a radius of at least 500 suns. We don"t know when betelgeuse will end its life could be tomorrow or could be another 2-3000 years. Well, interestingly enough, iron is the end point of this dying process. Thus, the core builds up in iron, all the time heating and growing. A logical question to ponder is how long does a typical high-mass star spend at each stage. Although it depends somewhat on the initial mass of the star the answer is an interesting one, as the following table portrays. Supernova explosion billion k 1 year: 5 billion k 6 months, 7 billion k 1 day, 4 billion k 0. 23 billion k milliseconds about 1 billion k hours.
