AST101H1 Lecture Notes - Lecture 14: Outer Core, Molecular Cloud

• School: UTSG
• Department: Astronomy & 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, collisions between particles flatten the orbit. Heavy materials (metals and rocks) within the frost line. Frost line: where gas gets far enough away from the sun it becomes liquid (the farther away it is, Light materials (h, he, ices) outside the frost line the (cid:373)o(cid:396)e (cid:858)solid(cid:859) it (cid:271)e(cid:272)o(cid:373)es(cid:895: pluto, for example, is made of stuff that on earth would be gas, but is solid on pluto. Based o(cid:374) whe(cid:396)e so(cid:373)ethi(cid:374)g is, you (cid:272)a(cid:374) p(cid:396)o(cid:271)a(cid:271)ly guess what it(cid:859)s (cid:373)ade of: the stuff earth is made up of is relatively rare. Terrestrial planets are inside the frost line. Tiny small objects stick together to form planetisimals. Inside the frost line, planetisimals are made of rock: gravity draws planetisimals together to form planets.