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The Celestial Sphere

• What is the celestial sphere?
• What is right ascension?
• What is declination?
• Which point is at 0 RA and 0 dec?

Special Locations on the Celestial Sphere

• What is special about Polaris, the North star?
• What is the declination of Polaris, the North Star?
• What is the ecliptic?
• What is the Zodiac?

Rotation of the Celestial Sphere

• Why don't we see the stars always in the same position in the sky?
• If a star is seen in the East, will it eventually set in the West like the Sun?

Motions on the Celestial Sphere

• Do stars and planets move on the celestial sphere?
• What is retrograde motion?
• Which objects move with retrograde motion?
• Does the Earth ever move in apparent retrograde motion?
• Where will a planet rise when it is in retrograde motion?
• What is conjunction, opposition?