In the southern hemisphere, we need to take into account that both southern latitudes on Earth and southern declination values have a minus sign. In the northern hemisphere, a star is circumpolar if its declination is larger than 90° minus the observer's latitude. Which stars are circumpolar depends on the observer's geographic latitude and on the star's declination – the latter is the angle between the star's location and the celestial equator. Those never-setting stars are called circumpolar stars. Our observer will never see those stars either rise or set. For stars that are close enough to the celestial pole, the traced-out circle will be completely above the horizon. At the two points where a circle crosses the observer's horizon, the star in question will rise and set, respectively. For an observer at such a location, the stars appear to rotate around the celestial pole as time passes: Each star traces a circle in the sky, with the circle centered on the celestial pole to which Earth's axis points. Description: In most locations on Earth, either the celestial North Pole or the celestial South Pole is visible in the sky at some distance above the horizon.
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