20. Which of the following best helps to explain why stars appear to revolve around Polaris, as viewed from the Northern Hemisphere?
Answer: D
Earth rotates on its axis.
The apparent revolution of stars around Polaris, as seen from the Northern Hemisphere, is due to the rotation of the Earth on its axis. This rotation causes the night sky to appear to move in a circular motion around the North Star, Polaris.
A) Earth and the rest of the solar system revolve around Polaris.
This option is incorrect because the solar system does not revolve around Polaris. Instead, the motion of stars around Polaris is an illusion created by the Earth's own rotation, not a result of the solar system's movement.
B) All stars revolve around Polaris.
This statement is misleading. While it may appear that stars revolve around Polaris, this is merely a perspective effect caused by Earth's rotation. In reality, stars are located at varying distances and are not all orbiting Polaris.
C) Polaris is at the center of the universe.
This option is incorrect as well. Polaris is not at the center of the universe; it is just a star located relatively close to Earth. The perception of stars revolving around it is due to Earth's axial rotation, not because Polaris occupies a central position in the universe.
D) Earth rotates on its axis.
This is the correct explanation for why stars appear to revolve around Polaris. The Earth's rotation causes the sky to change position throughout the night, creating the illusion of stars moving in circular paths around Polaris.
Conclusion
The correct answer, that Earth rotates on its axis, clearly explains the observed motion of stars around Polaris. All other options misrepresent the relationship between Earth, Polaris, and the stars, failing to acknowledge that the apparent motion is a result of Earth's own rotation rather than any movement of the solar system or Polaris itself.