Answer:
The reason why the student sees different patterns of stars in summer than those he sees in winter is due to the Earth's tilt on its axis. The Earth is tilted at an angle of 23.5 degrees, which means that the angle of the Earth's rotation changes with respect to the stars throughout the year. In the summer, the Earth's axis is tilted towards the Sun, which causes the stars of the Northern Hemisphere to be visible during the night, while the stars of the Southern Hemisphere are visible during the day. In the winter, the Earth's axis is tilted away from the Sun, and the stars of the Southern Hemisphere are now visible at night, while the stars of the Northern Hemisphere are visible during the day