AST101H1 Lecture Notes - Lecture 14: Molecular Cloud, Radioactive Decay

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

Document Summary

The force of gravity pulls a molecular cloud (made of gas and dust) together. As it collapses, it begins to spin faster (conservation of momentum) Forms a spinning disk of gas and dust. Tiny small objects stick together to form planetesimals, inside the frost line, planetesimals are made of rock. S waves and p waves behave differently in different materials. Differentiation caused all of the terrestrial planets to form cores. Only the earth and moon have seismometers on them. For the rest, the size of the core is inferred from the mass of the planet and magnetic fields. In the early solar system, accretion was the most important. A planets mantle is not completely rigid. Hot rock rises and cooler rock falls. This brings heat up from the core. A planets crust is ridged, so there is no convection there than convection)