AST101H1 Lecture Notes - Lecture 1: Gas Giant, Semi-Major And Semi-Minor Axes, Lunar Eclipse

• School: UTSG
• Department: Astronomy & Astrophysics
• Course: AST101H1
• Professor: Michael Reid

Document Summary

What does solar system mean - one or more stars plus the bodies orbiting it/them. What does universe mean the totality of space, time, energy and matter. Cosmic address - earth, sol system, milky way galaxy, local group, universe. How big is space you are wrong (infinite) Most different in size observable universe 10^27 human 1m (earth 10^13 proton10^-15,) Q. max distance from earth and mars - 2. 5au. Earth 1/10 diameter jupiter, jupiter 1/10 of sun. Solar system is huge and vastly empty* tiny, tiny quantities of gas and dust. Sun to earth 1 au (astronomical unit) 1. 5 x 10^11m. A light year is a measure of - distance. Distance light travels in one year 4. 4 ly from nearest star to sun. 1ly = 63,000 au 1 au = 8 light minutes. If it fails this it becomes a dwarf planet (pluto, Be big enough for the gravity pressure to compress them in sphere ceres)