ASTR 114 Lecture Notes - Lecture 10: Potential Energy, Convection Zone, Radiation Zone

• School: Binghamton University
• Department: Astronomy
• Course: ASTR 114
• Professor: Christopher A.Taylor

Document Summary

Lecture 10: as long as the sun shines. The sun is not on fire the sun would only be able to burn for 10,000 years based on its size and luminosity. It also is(cid:374)"t co(cid:374)tracti(cid:374)g the sun would only last about 25 million years, and the earth has been around for billions of years already. The sun is more than likely powered by nuclear energy (e = mc2): the nuclear potential energy at the core divided by the luminosity would give the sun about 10 billion years. The sun is constantly pushed inward by gravitational force, and has an equal amount of pressure pushing outward due to fusion. Solar wind: a flow of charged particles from the surface of the sun. Corona: outermost layer of the solar atmosphere, 1 million k. Chromosphere: middle layer of the solar atmosphere, 104 105 k. Photosphere: visible surface of the sun, 6000 k. Convection zone: energy transported upward by rising hot gas.