AST201H1 Lecture Notes - Lecture 1: Stellar Evolution, Thermostat, Degenerate Matter
22 Apr 2017
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AST201H1 Full Course Notes
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Lecture 1 a very big mystery: the dark universe (january 5th) Identify one piece of evidence for the existence of dark matter: de(cid:448)elop (cid:455)ou(cid:396) (cid:449)illi(cid:374)g(cid:374)ess to ask (cid:862)wh(cid:455)? (cid:863) a(cid:374)d (cid:862)ho(cid:449) do (cid:449)e k(cid:374)o(cid:449)? (cid:863) Is a(cid:374) i(cid:373)age of a s(cid:373)all (cid:396)egio(cid:374) of spa(cid:272)e i(cid:374) the (cid:272)o(cid:374)stellatio(cid:374) (cid:858)fo(cid:396)(cid:374)a(cid:454)(cid:859), (cid:272)o(cid:374)tai(cid:374)i(cid:374)g a(cid:374) esti(cid:373)ated. Reveals galaxies that date back 13. 5 billion years: between 400 to 800 million years after big bang. Overall composition of the universe: normal matter (4. 9%) Stars, galaxies, planets, gas, dust, etc: dark matter (26. 8%, dark energy (68. 3%) The speed of an object in a given direction: acceleration. Increase in the rate of speed of an object. The rate of velocity of an object in respect to time. Application of velocity and acceleration to describe the motion of objects: we can only measure motion relative to a given frame of reference, e. g. the speed of a ball on a plane and on the ground, is different.
