ASTR 1P01 Lecture Notes - Celestial Pole

• School: Brock University
• Department: Astronomy
• Course: ASTR 1P01
• Professor: Bozidar Mitrovic

Document Summary

The displacement of the stars in their daily motions is 360 per hour. The earth also revolves around the sun (once every 365. 25 days) As a result this motion becomes noticeable over a period of a fer weeks or a month. As a result of this motion the old constellations disappear in the west and the new ones appear in the east. Also stars rise and set about 4minutes (3minutes and 56 seconds) every day. To describe the daily and annual motions of stars we use the concept of celestial sphere. Celestial sphere - an imaginary sphere centred on earth whose radius is much larger than the earth to sun distance. The important points an lines on celestial sphere: zenith- the point directly overhead an observer, north celestial pole(ncp)- the point directly above the earth"s north pole.