AST101H1 Lecture Notes - Lecture 10: Solar Maximum, Solar Minimum, Helioseismology

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

Document Summary

E= energy, m=mass, c2 =speed of light (squared) When a nuclear reaction produces energy, that energy comes from converting mass into energy. Enough fuel for 10 billion years (we"re around half-way through) Only part of the sun that is hot enough. The sun wobbles, vibrating at slightly different speeds because they are made of slightly different things. Hot gas has pressure, which tries to make the sun expand. Gravity pulls inward, which tries to make the sun collapse. The inner regions have to hold up more weight. Too hot: too many fusion reactions, sun heats up more, raises pressure (off balance), core will expand and so it will cool down, temp lowers, back to normal. Too cold: gets smaller, more pressure, gets hotter, back to normal. Forced to stay at the same temp at the same energy rate. Cooler regions on surface (temperature only around 3500 c) Strong magnetism prevents hot gas from rising up.