AST101H1 Lecture Notes - Lecture 3: Celestial Pole, Night Sky, Celestial Equator

• School: UTSG
• Department: Astronomy & Astrophysics
• Course: AST101H1
• Professor: Bryan Gaensler

Document Summary

Constellation: a region of the sky with well-defined borders. The familiar patterns of stars merely help us locate the constellations !! The celestial sphere: the imaginary sphere on which objects in the sky appear to reside when observed from earth. Stars are actually very far apart in reality but appear to lie close to one another because they lie at very different distances from earth. As a result, we lack depth perception when we look into space as the stars are super far away. North celestial pole: poi(cid:374)t di(cid:396)e(cid:272)tl(cid:455) o(cid:448)e(cid:396) ea(cid:396)th"s no(cid:396)th pole. South celestial pole: poi(cid:374)t di(cid:396)e(cid:272)tl(cid:455) o(cid:448)e(cid:396) ea(cid:396)th"s south pole. Celestial equator: a p(cid:396)oje(cid:272)tio(cid:374) of ea(cid:396)th"s e(cid:395)uato(cid:396) i(cid:374)to spa(cid:272)e, a (cid:272)o(cid:373)plete circle around the celestial sphere. Ecliptic: path the sun follows as it appears to circle around the celestial sphere once each year. It crosses the (cid:272)elestial e(cid:395)uato(cid:396) at a (cid:1006)(cid:1007). 5 deg(cid:396)ees a(cid:374)gle (cid:271)e(cid:272)ause that is the tilt of ea(cid:396)th"s a(cid:454)is.