AST 1001 Lecture Notes - Lecture 1: Almagest, Food Energy, Electromagnetic Spectrum
Document Summary
Lecture notes: what is our place in the universe, earth is a planet in our solar system. The sun and the other visible stars belong to a huge collection of stars known as the milky way galaxy. On larger scales, we see chains sheets, and clusters of galaxies separated by huge empty spaces: how did we come to be, birth of the universe: the expansion of the universe began with the hot and dense. The cubes show how one region of the universe has expanded with time. 98% is hydrogen (h) and helium (he) 2% in everything else (heavy elements or metals) Planets may be rocky, icy, or gaseous in composition: moon (or satellite)- any object that orbits a planet. Moon orbits the earth: asteroid- a. k. a. minor planets; a relatively small and rocky object that orbits a star. Non- spherical (gravity: comet- a relatively small and icy object that orbits a star.
