4.1.3 The Moon – some facts
The Moon is about 4.5 billion years old. Current thought is that it was most likely formed by a giant impact, as you saw in Week 1.
The distance to the Moon is known accurately due to reflectors that were placed on it during the Apollo missions. The reflectors, part of the Lunar Laser Ranging Experiment, allow lasers to be shone onto the Moon and the time taken for the laser light to get there and back can be measured. It is then possible, using a simple equation, to calculate the distance to the Moon. You can.
Next, you have a chance to try calculating the distance to the Moon for yourself. It’s a very basic non-scored quiz. Don’t worry if you don’t know some of the answers.