Why do the stars and the constellations in the sky appear to change positions throughout the night and throughout the year

Answer 1

The apparent change in positions of stars and constellations in the sky throughout the night and the year is due to Earth's rotation and revolution around the Sun.

Earth's rotation: The Earth rotates on its axis, completing one rotation every 24 hours, causing day and night. As the Earth rotates, observers on its surface perceive the celestial objects moving across the sky from east to west. This rotation causes the stars and constellations to appear to change positions throughout the night.

Earth's revolution: The Earth revolves around the Sun in an elliptical orbit, completing one revolution approximately every 365.25 days, causing the change in seasons. Since we observe the sky from a constantly shifting position as Earth revolves around the Sun, it leads to an apparent change in the positions of stars and constellations throughout the year. As Earth moves, different parts of the sky become visible, and different constellations come into view.

The combination of Earth's rotation and revolution cause the stars and constellations to appear at different positions and times throughout the night and the year.