Astronomy 1021 Lecture Notes - Lecture 3: Cosmic Dust, Dailymotion, Orbital Period

• School: Western University
• Department: Astronomy
• Course: Astronomy 1021
• Professor: Robert Cockcroft

Document Summary

Gets higher in the southern part of the sky. The stars in the southern part of the sky. Appears to rotate around north pole star. North on horizon immediately below north pole star. Circumpolar stars don"t appear to rise or set. The circle that defines circumpolar stars changes with latitude. When you"re standing at the equator there is no circumpolar stars. Standing at the north pole would result in the whole sky being circumpolar. Earths motion around sun: earth"s orbital motion around the sun is in the same sense as earth"s rotation on its axis. Venus rotates on its axis in the opposite direction to the other planets. All planets orbit around the sun in the same direction as the earth. Solar system formed from a cloud of gas and cosmic dust. Small initial rotation increases as cloud collapses under self-gravity. Seasons are caused by the earth"s axial tilt (23. 5 degrees)