north celestial pole
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Definition
Noun: The point in the celestial sphere directly above Earth's geographic North Pole. It is the point around which the stars in the northern sky appear to rotate. This pole is located near the star Polaris (the North Star).
Usage
The term "north celestial pole" is used in astronomy and navigation to describe a fixed reference point in the sky. * To locate the north celestial pole, first find the Big Dipper constellation. * Because Earth's axis points nearly at it, Polaris appears very close to the north celestial pole. * The altitude of the north celestial pole above your horizon equals your geographic latitude.
Advanced Usage
- Celestial Navigation: The north celestial pole is a fundamental reference for determining direction and latitude in the Northern Hemisphere.
- Astrophotography: Long-exposure photographs centered on the north celestial pole show star trails as concentric circles.
Variants and Related Words
- Celestial Pole (noun): The general term for either of the two points (north and south) where Earth's axis of rotation intersects the celestial sphere.
- South Celestial Pole (noun): The point in the celestial sphere directly above Earth's geographic South Pole.
Synonyms
- NCP (abbreviation)
- North Pole of the heavens
Related Concepts
- Polaris (noun): The current North Star, which lies very close to the north celestial pole.
- Celestial Sphere (noun): An imaginary sphere of arbitrarily large radius, concentric with Earth, on which all celestial objects appear to be projected.
- Axis of Rotation (noun): The line through Earth's center and geographic poles, extended to meet the celestial sphere at the celestial poles.
Noun
- the celestial pole above the northern hemisphere; near Polaris