Celestial poles

Definition

Celestial poles are the two imaginary points in the sky where Earth's axis of rotation, indefinitely extended, intersects the celestial sphere. The North Celestial Pole is near Polaris, while the South Celestial Pole does not have a bright star marking its position.

5 Must Know Facts For Your Next Test

1. The North Celestial Pole aligns closely with Polaris, also known as the North Star.
2. Celestial poles are crucial for navigation and understanding star movements.
3. As Earth rotates, stars appear to move in circular paths around the celestial poles.
4. The altitude of the celestial pole above your horizon is equal to your latitude on Earth.
5. Precession causes the positions of celestial poles to change gradually over a period of about 26,000 years.

Review Questions

• What is the relationship between your latitude and the altitude of a celestial pole?
• Why is Polaris important when studying celestial poles?
• How does precession affect the positions of celestial poles over time?

Related terms

Celestial Sphere: An imaginary sphere surrounding Earth upon which all celestial objects appear to lie.

Polaris: A bright star located nearly at the North Celestial Pole, commonly known as the North Star.

Precession: The slow movement of Earth's axis that changes the coordinates of stars and celestial poles over millennia.