4.5 billion years old
Hope this helps!!!
Day and night is due to the earth rotating. Seasons are due to the earth rotating on a slightly tilted axis, causing light to be shone on different parts of the earth more directly during different parts of the year. Constellations changing throughout the night are because of the earth moving and rotating. Throughout the year, the earth moves, causing us to be facing different directions in different parts of the year. The North Star does't move because it is close to Earth's line of axis, and therefore does not appear to move.
