This preview shows pages 1–3. Sign up to view the full content.
This preview has intentionally blurred sections. Sign up to view the full version.View Full Document
Unformatted text preview: Precession is SLOW (about 26,000 years) to go around once. Motions: daily motion arise from the rotation (spin) of Earth causes the rising and setting each day of the Sun, Moon and stars If nothing else moved . ....... then motions are simple. The sun would rise at the same time every day ! But . .... Earth is also moving around the Sun. => it takes a little more than one full rotation of Earth for Sun to rise again. So how long is a day ? • sunrise to sunrise ? . .................. = "solar day" • one rotation of the Earth (with respect to the stars) ? . ....................... = "siderial day" "siderial" = with respect to the stars Average solar day is about 4 minutes longer than the siderial day....
View Full Document
This note was uploaded on 03/09/2012 for the course AST 1002 taught by Professor Emilyhoward during the Spring '10 term at Broward College.
- Spring '10