GSC 111 Lecture Notes - Lecture 10: Cosmic Microwave Background, Crab Nebula, Planetary Nebula
26 Nov 2017
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Document Summary
A look 13. 7 bya in time at a few of the 170 billion galaxies in the universe. Trace universe back to its original point of its initial point. 10-12 sec: protons and neutrons form (1032k) 0. 01 sec- electrons form (100 bill k) 3 mins- 1st hydrogen atoms form (1 bill k) Red shift of light emitted from distant galaxies. Est. age of the universe is about 13. 7 bya. Doppler effect perceived shift of wavelength between moving object. Caused by interactions of photons, electrons, protons. Stopped forming about 380,000 yrs after the big bang when the universe cooled below. T variation of few hundred of a thousandths of a degree. Pick up different type of wavelength than a light telescope picks up. Galaxies start to form after a billion years. Milky way galaxy contains about 300 billion stars. Interstellar cloud of dust, hydrogen gas, and plasma within a galaxy. Gravitational forces cause the nebula to collapse and form a star.
