how long should it take the voices of astronauts on the moon to reach the earth? assume that the only significant time is the transit time from the earth to the moon, at the speed of light. suppose that the astronaut on the surface of the moon, the receiver on the surface of the earth, and the centers of the earth and the moon are aligned. the distance between the centers of the earth and the moon is 384×103km, the radius of the earth is 6.38×103km, the radius of the moon is 1.74×103km.