The sky seems to turn as Earth rotates
You cannot see all of the constellations at once, because Earth blocks half of space from your view.
You can see a parade of constellations each night as Earth rotates because stars move from east to west. If you extended the North Pole into space, it would point almost exactly to a star called Polaris, or the North Star. You can use Polaris to figure out direction and location.
The movements of planets and other nearby objects are visible from Earth.
Stars are always moving , but they are so far away that you cannot see their movements.
By contrast, the Moon moves across the star background a distance equal to its width every hour as it orbits Earth. The planet’s gradual movements are visible among the constellations over a period of weeks or month.
The apparent movement of the sky led early astronomers to believe that Earth was at the center of the universe. Later astronomers discovered that Earth and the other planets orbit the Sun.
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