Star Motion

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      Latitude = 41°       Bearing = 180°

This simulation shows the apparent motions of the stars, caused by the earth’s daily rotation, as viewed from earth’s surface. The motion is much faster than in the real sky, where a full cycle takes 23 hours and 56 minutes. The view shows half the visible sky, 180° from side to side, with the horizon at the bottom and zenith at the top. Only the brightest stars (to magnitude 4.0) are shown. The sun, moon, and planets are not shown, nor is the scattered sunlight that we call daylight—so the sky is always dark, letting you see the stars move through their full cycles. Initially you are facing south, but you can use the Bearing slider to change the direction you face.

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