AST101H1 Lecture Notes - Lecture 10: Photosphere, Photon, Nuclear Reaction

• School: UTSG
• Department: Astronomy & Astrophysics
• Course: AST101H1
• Professor: Bryan Gaensler

Document Summary

Einstein"s famous equation: e = m x c2 c: speed of light (squared) m : mass. When a nuclear reaction produces energy, that . 4 x hydrogen > 1 helium (this is the pp chain) Sun"s mass decreases every second by 4 tonnes. Problem: the chances of 4 protons colliding simultaneously is tiny. Also creates neutrinos, tiny particles that go through almost anything (detectable) Enough fuel for 10 billion years (currently half way through) Each photon of light travels approx 0. 1mm before being randomly deflected. Hot gas has pressure, makes sun expand. Gravity pulls inward, which tries to make the sun. Inner regions hold up more weight = more collapse pressure = hotter. Are cooler regions on the surface and usually come in pairs. Strong magnetism prevents hot gas from rising up. Goes from lots to almost none on 11 year cycle. Pattern seen going back approx 400 years. Wavelength: distance between two peaks (or troughs)