How long does it take for radio signals to travel from Earth to the Moon (and vice versa)?

The distance from Earth to the Moon is approximately 238,855 miles (384,400 kilometers). Radio waves travel at the speed of light, which is about 186,282 miles per second (299,792 kilometers per second).

To calculate the time it takes for a radio signal to travel from Earth to the Moon, you would divide the distance by the speed of the radio waves.

In miles: 238,855 miles ÷ 186,282 miles/second = approximately 1.28 seconds

In kilometers: 384,400 kilometers ÷ 299,792 kilometers/second = approximately 1.28 seconds

So, it takes about 1.28 seconds for a radio signal to travel from Earth to the Moon. The same amount of time would be needed for the signal to travel back from the Moon to Earth, so the round trip would take about 2.56 seconds.