Which group of stars appears to circle the sky because of Earth's rotation?

• A. Pole stars
• B. Zodiac stars
• C. North stars
• D. Circumpolar stars

Answer: (D)

Earth’s rotation makes the sky appear to rotate, so stars that lie close to the celestial poles never set below the horizon. They trace circular paths around the pole as the night goes on. That group is circumpolar stars. The farther you are from the equator, the more of the sky consists of circumpolar stars, because the poles sit high above the horizon and provide those looping paths. Polaris, near the north celestial pole, is a familiar reference point: the other circumpolar stars seem to whirl around it all night.