Question

Why is Earth's orbit used instead of its diameter to measure distances to stars using the parallax method?

Options

• Stars move too fast

• Air blocks the view

• Earth’s diameter is too small

• Sun bends the light

Answer 1

Earth’s diameter is too small

Reason:

The angle shift (parallax) is tiny for faraway stars. Earth’s diameter is too short to notice this shift, but Earth's orbit around the Sun is much wider, making the angle easier to measure.