How do we most accurately measure the distance to the Moon?
A) We measure the lunar period and use Kepler's Third Law.
B) We bounce a pulse of light off the lunar surface and measure how long the trip takes.
C) We know how long it took Apollo astronauts to get there, and how fast the rocket traveled.
D) We measure its angular size and compare it to its actual diameter, which gives us its distance.
E) All of these choices provide equally accurate measurements.

Question

Quizplus · Accepted Answer

We most accurately measure the distance to the Moon by using laser ranging, where a pulse of light is bounced off retroreflectors on the lunar surface and the time it takes for the light to return is measured. This method provides precise measurements.

How Do We Most Accurately Measure the Distance to the Moon