Constellation Quiz Workshop

1. Constellation Quiz Workshop Learn the data on the Constellation Quiz Data Sheet: - constellation shapes and names - star names and position in constellation - deep sky objects’ names and position Quiz: You will be asked to find these objects on a star map.

2. Constellations of Stars About 5000 stars visible with naked eye About 3500 of them from the northern hemisphere Stars that appear to be close are grouped together into constellations since antiquity Officially 88 constellations (with strict boundaries for classification of objects) Names range from mythological (Perseus, Cassiopeia) to technical (Air Pump, Compass)

3. Constellation 1: Orion Orion as seen at night Orion as imagined by men

4. Orion “from the side” Stars in a constellation are not connected in any real way; they aren’t even close together!

5. Constellation 1: Orion “the Hunter” Bright Stars: D) Betelgeuze E) Rigel Deep Sky Object: i) Orion Nebula

6. Constellation 2: Gemini “the Twins” zodiacal sign Brightest Stars: I) Castor J=K) Pollux

7. Constellation 3: Taurus “the Bull” zodiacal sign Brightest Star: F) Aldebaran Deep Sky Object: iii) Plejades

8. Constellation 4: Ursa Major Other name: Big Dipper Stars: B) Dubhe C) Merak Navigation: go 5 times the distance from Merak to Dubhe and you are at Polaris.

9. Constellation 5: Ursa Minor Other name: LittleDipper α Ursa Minoris is Polaris [A], the pole star

10. Constellation 6: Canis Major “Big Dog” Stars: H) Sirius (brightest fixed star)

11. Constellation 7: Cancer “Crab” No bright Stars

12. Constellation 8: Leo “the Lion” zodiacal sign Brightest Star: G) Regulus

13. Constellation 9: Cassiopeia Greek mythological figure: mother of Andromeda the big “W” in the sky No bright stars

14. Constellation 10: Pisces “the Fishes” Zodiacal sign No bright stars

15. Constellation 11: Pegasus Greek mythological figure: the winged horse big rectangle in the sky No bright stars

16. Constellation 12: Andromeda Greek mythological figure: Daughter of Queen Cassiopeia and King Cepheus rescued from Cetus by Perseus Deep Sky Object: Andromeda Galaxy

17. The Seasons • Change of seasons is a result of the tilt of the Earth’s rotation axis with respect to the plane of the ecliptic • Sun, moon, planets run along the ecliptic

18. Position of Ecliptic on the Celestial Sphere • Earth axis is tilted w.r.t. ecliptic by 23 ½ degrees • Equivalent: ecliptic is tilted by 23 ½ degrees w.r.t. equator! •  Sun appears to be sometime above (e.g. summer solstice), sometimes below, and sometimes on the celestial equator

19. Zodiacal signs vs. Constellations • “Constellation” is a modern, well-defined term • - Some constellations are big, some are small on the celestial sphere • “Zodiacal sign” is the old way of dividing the year and the Sun’s path into 12 equal parts • 360/12=30, so each zodiacal sign is exactly 30 degrees “long” • 0 degrees: Aries, 30 degrees: Taurus, 60 degrees: Gemini, 90 degrees: Cancer, etc.

20. Example The vernal equinox happens when the sun enters the zodiacal sign of Aries, but is actually located in the constellation of Pisces.