Definition:North Celestial Pole

Definition

Let $O$ be a celestial observer situated at the surface of Earth in the Northern hemisphere.

Let $OP$ be a straight line parallel to Earth's axis.

Let $P$ be the point in the visible hemisphere at which $OP$ meets the celestial sphere.

Then $P$ is the north celestial pole.

That is, the north celestial pole is the pole of the celestial equator which is the zenith of the North Pole.

In the above diagram, the north celestial pole is indicated by $P$.

Also known as

The north celestial pole is also referred to as the north pole, but this can be confused with the North Pole of Earth itself.

Also see

• Definition:South Celestial Pole

• Definition:Celestial Axis
• Definition:Celestial Equator

Sources

• 1976: W.M. Smart: Textbook on Spherical Astronomy (6th ed.) ... (previous) ... (next): Chapter $\text {II}$. The Celestial Sphere: $18$. Altitude and azimuth.
• 1998: David Nelson: The Penguin Dictionary of Mathematics (2nd ed.) ... (previous) ... (next): celestial equator
• 1998: David Nelson: The Penguin Dictionary of Mathematics (2nd ed.) ... (previous) ... (next): celestial sphere
• 2008: David Nelson: The Penguin Dictionary of Mathematics (4th ed.) ... (previous) ... (next): celestial equator
• 2008: David Nelson: The Penguin Dictionary of Mathematics (4th ed.) ... (previous) ... (next): celestial sphere