Celestial sphere: imaginary sphere for stars with earth at. Shows where all stars lie on the surface. Celestial equator: divides sphere into north and south poles. North (ncp)/south celestial pole (scp): imaginary points in the sky above the north and south pole of earth. Ncp is located very close to north star (polaris) looks like all the other stars move around. Sometimes ncp isn"t directly above for different places on earth; can be tilted. When tilted, stars look like they rise and set around horizon. Altitude of ncp = your latitude (n/s direction) Circumpolar stars: never set bc they"re close to one of the celestial poles. How many stars are circumpolar depends on how far north or south you are from equator. ***again: ncp can be tilted depending on where you are. Figured out that the sun is high at noon during summer months and low at noon during winter months.