AST101H5 Lecture Notes - Ancient Greek Astronomy, Astronomical Object, Deep Time

45 views2 pages

Document Summary

Chapter one - our place in the universe (sept. 9) Only concentrate on the relevant topics discussed in lectures. Glossary: g1-g14 at the end of textbook. Earth is not the centre of the universe, universe is not geocentric . Geo = earth; centric = centered on. Believed that the earth was the centre of the universe from the time of greek astronomy (2200 years ago) until about the year 1500. Earth is insigni cant, except that we live here. The sun and all objects orbiting around the sun. The whole system formed billions of years ago. There are many other solar systems , far beyond our system. Sun = heart of the solar system, but it is just an ordinary star, like billions of others. Words like big do not have enough information, we need to use numbers (no memorization required learn how we know the number and what it means)