1. Mapping the Celestial sphere Locating stars and deep space objects

2. Important Terms Celestial: Anything referring to the “heavens”, or space above us Celestial Sphere: The night sky that looks like it is a painted dome above us

3. Terms Cont’d Celestial Poles: Points on the celestial sphere directly above the North and South Pole Celestial North Pole: Has the North Star, Polaris Celestial South Pole: Has no Southern Star

4. Terms Cont’d Celestial Equator: The line on the celestial sphere that is directly over the equator

5. Terms Cont’d Zenith: Imaginary point on celestial sphere directly overhead (90°)

6. Nadir: Exact opposite of the Zenith You cannot see it

7. Terms Cont’d Horizons: Place where the earth and sky appear to meet Halfway between zenith and nadir

8. 2 terms we use to describe objects’ locations 1. Declination = Celestial Latitude Measured in Degrees 2. Right Ascension= Celestial Longitude Measured in time.

9. Location of a star Betelgeuse RA: 5h 55m 10.2s east of vernal equinox Dec: 7°24’26” north of celestial equator

10. HOW WE LOCATE STARS IN THE CELESTIAL SPHERE 3Ways: 1. Finding it relative to other markers (Celestial equator/poles, zenith, horizon, etc…) 2. Finding it within a constellation (often in terms of brightness) 3. Using Right Ascension and Declination

11. Constellations Constellations: A group of stars that appear to form a pattern in the sky.

12. Starlight, Star Bright…. The 1 st method of categorizing the brightness of stars: Magnitude 6 = barely seen with the unaided human eye. 5 = 2.5 times as bright as a 6 4 = 2.5 times as bright as a 5 3 = 2.5 times as bright as a 4 2 = 2.5 times as bright as a 3 1 = the brightest (then)

13. Apparent Magnitude Rating system has added numbers lower than 1 for VERY bright stars and numbers higher than 6 for objects only able to be seen by a telescope. System of rating is dependent on how the star appears from Earth.

14. Bayer Designation System Naming stars within constellations A Greek letter is given to each star in the constellation according to it brightness. The brightest star is the “alpha star”, the next brightest is the “beta star”, and so forth.

15. Bayer Designation System & Apparent Magnitude StarBayer DesignationApparent Magnitude SiriusAlpha Canis Majoris-1.46 VegaAlpha Lyrae0.03 RigelBeta Orionis0.12 BetelgeuseAlpha Orionis0.7 AntaresAlpha Scorpii0.96 PolarisAlpha Ursae Minoris2.02

16. Constellation Visibility Summer Winter Earth Moves around the sun = different position

17. Constellations Changing Shape Stars move at very fast speeds, from 3 to 122 km / s Stars are so very far apart and so very far from us, they do not appear to change at all. The constellations do change over very large time periods, however.