PHYS 183 Chapter Notes - Chapter 1: Elliptic Geometry, Observable Universe, Ecliptic
Document Summary
1. 1 our modern view of the universe star: a large, glowing ball of gas that generates heat & light through nuclear fusion in its core. Planet: a moderately large object that orbits a star & shines primarily by reflecting light from its star. Moon (satellite): an object that orbits a planet. Galaxy: a great island of stars in space containing a few hundred million to a trillion stars all held together by gravity and orbiting a common centre; scattered throughout space; some isolated, others in groups. Milky way galaxy: relatively large galaxy containing more than 100 billion stars; the galaxy that we live in; one of the two largest among 40 galaxies in the local group. Galaxy cluster: groups of galaxies with more than a few dozen members bound together by gravity supercluster: regions in which galaxies and galaxy clusters are most tightly packed clusters of galaxy clusters. Universe: sum total of all matter and energy.
