► Is the Moon getting farther away from Earth? – Judah, 9, Broken Arrow, Oklahoma

The Moon is getting 1½ inches (3.8 centimeters) farther away from the Earth every year.

Scientists measure the distance to the Moon by bouncing lasers off mirrors placed there by space probes and astronauts.

By measuring the amount of time it takes light to travel to the Moon and back, scientists can very precisely measure the distance to the Moon and how the distance changes.

The distance to the Moon actually changes over a single month as it goes around the Earth. The Moon is typically 239,000 miles (385,000 km) away from the Earth, but its orbit is not a perfect circle and changes by about 12,400 miles (20,000 km) as it orbits the Earth. This change is why some full moons are a bit bigger than other

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