![Page 1: Astronomy is a nocturnal activity 1953, T. E. Houck and A. D. Code](https://reader035.vdocument.in/reader035/viewer/2022070408/56649e685503460f94b64eaf/html5/thumbnails/1.jpg)
Astronomy is a nocturnal activity
1953, T. E. Houck and A. D. Code
![Page 2: Astronomy is a nocturnal activity 1953, T. E. Houck and A. D. Code](https://reader035.vdocument.in/reader035/viewer/2022070408/56649e685503460f94b64eaf/html5/thumbnails/2.jpg)
The sky above us
![Page 3: Astronomy is a nocturnal activity 1953, T. E. Houck and A. D. Code](https://reader035.vdocument.in/reader035/viewer/2022070408/56649e685503460f94b64eaf/html5/thumbnails/3.jpg)
Stars dominate the night sky
• Relative positions of stars remains fixed• The whole pattern revolves around us• Constellations – patterns in star
distribution• Constellations vary – related to mythology• Constellations not real• 1929 IUA – 88 official constellations• Every star belongs to a constellation
![Page 4: Astronomy is a nocturnal activity 1953, T. E. Houck and A. D. Code](https://reader035.vdocument.in/reader035/viewer/2022070408/56649e685503460f94b64eaf/html5/thumbnails/4.jpg)
Orion Constellation
![Page 5: Astronomy is a nocturnal activity 1953, T. E. Houck and A. D. Code](https://reader035.vdocument.in/reader035/viewer/2022070408/56649e685503460f94b64eaf/html5/thumbnails/5.jpg)
Map of Orion Constellation
![Page 6: Astronomy is a nocturnal activity 1953, T. E. Houck and A. D. Code](https://reader035.vdocument.in/reader035/viewer/2022070408/56649e685503460f94b64eaf/html5/thumbnails/6.jpg)
The wanderers
• Sun, Moon, planets move relative to stars
• Wander in a narrow band – Zodiac
• Ecliptic
![Page 7: Astronomy is a nocturnal activity 1953, T. E. Houck and A. D. Code](https://reader035.vdocument.in/reader035/viewer/2022070408/56649e685503460f94b64eaf/html5/thumbnails/7.jpg)
The Zodiac
![Page 8: Astronomy is a nocturnal activity 1953, T. E. Houck and A. D. Code](https://reader035.vdocument.in/reader035/viewer/2022070408/56649e685503460f94b64eaf/html5/thumbnails/8.jpg)
The Ecliptic
![Page 9: Astronomy is a nocturnal activity 1953, T. E. Houck and A. D. Code](https://reader035.vdocument.in/reader035/viewer/2022070408/56649e685503460f94b64eaf/html5/thumbnails/9.jpg)
The Celestial Sphere
23.5
![Page 10: Astronomy is a nocturnal activity 1953, T. E. Houck and A. D. Code](https://reader035.vdocument.in/reader035/viewer/2022070408/56649e685503460f94b64eaf/html5/thumbnails/10.jpg)
Earth’s prograde rotation
![Page 11: Astronomy is a nocturnal activity 1953, T. E. Houck and A. D. Code](https://reader035.vdocument.in/reader035/viewer/2022070408/56649e685503460f94b64eaf/html5/thumbnails/11.jpg)
Ursa Minor
![Page 12: Astronomy is a nocturnal activity 1953, T. E. Houck and A. D. Code](https://reader035.vdocument.in/reader035/viewer/2022070408/56649e685503460f94b64eaf/html5/thumbnails/12.jpg)
Precession of Earth’s spin
26,000 years period
![Page 13: Astronomy is a nocturnal activity 1953, T. E. Houck and A. D. Code](https://reader035.vdocument.in/reader035/viewer/2022070408/56649e685503460f94b64eaf/html5/thumbnails/13.jpg)
Equatorial Coordinates
![Page 14: Astronomy is a nocturnal activity 1953, T. E. Houck and A. D. Code](https://reader035.vdocument.in/reader035/viewer/2022070408/56649e685503460f94b64eaf/html5/thumbnails/14.jpg)
Examples
• Orion:
• Right Ascension: 5 hours
• Declination: 5 degrees
• Ursa Major = Saptarshi Mandal
• The Great Bear (Big Dipper)
• Right Ascension: 11 hours
• Declination: 50 degrees
![Page 15: Astronomy is a nocturnal activity 1953, T. E. Houck and A. D. Code](https://reader035.vdocument.in/reader035/viewer/2022070408/56649e685503460f94b64eaf/html5/thumbnails/15.jpg)
Image Sources
![Page 16: Astronomy is a nocturnal activity 1953, T. E. Houck and A. D. Code](https://reader035.vdocument.in/reader035/viewer/2022070408/56649e685503460f94b64eaf/html5/thumbnails/16.jpg)
Image Sources
http://fourmilab.ch/yoursky/
![Page 17: Astronomy is a nocturnal activity 1953, T. E. Houck and A. D. Code](https://reader035.vdocument.in/reader035/viewer/2022070408/56649e685503460f94b64eaf/html5/thumbnails/17.jpg)
Image Sources