Observing the Sky: Motion of the Sun and Stars - The Night Sky

If you watch the night skies you'll notice that the same stars aren't visible all year long. That's because our point of view changes as the Earth revolves around the Sun. If you look at the stars tonight, then again in six months when the Earth has moved around to the other side of the Sun, you will see a whole different set of stars.

As the Earth moves forward along its orbit, the Sun seems to drop backward among the stars, making the stars seem to rise earlier each night. The Sun's path stays the same, so it blocks the stars from view in a predictable pattern year after year.