The Moon Is Truly Moving Away from Earth, Here Are the Impacts

Although the average distance between the Earth and the Moon is around 384,400 kilometres, that position is not actually static. In fact, the Moon has been observed to be gradually drifting further away from the Earth.

This shift in distance has been successfully monitored through the Lunar Laser Ranging Experiment. During the Apollo missions of the 1960s, astronauts deliberately installed special reflector panels on the Moon’s surface to measure its precise distance from Earth.

The method for calculating this distance involves measuring the time it takes for a laser beam to be reflected back by the reflector. From these calculations, it has been determined that the two bodies are continuously moving apart at a rate of 3.8 centimetres per year.

This change certainly has consequences, at least for the phenomenon of total solar eclipses in the future.

IFL Science explains that the Moon’s recession will eventually make total solar eclipses impossible to observe, given that the apparent size of the Moon’s disc as seen from Earth is steadily shrinking.

At present, the apparent sizes of the Sun and the Moon are nearly identical. This is why people on Earth can still witness the Moon completely covering the Sun’s surface during such eclipses.

“As time goes on, the number and frequency of total solar eclipses will decrease. In about 600 million years, Earth will witness the beauty of a total solar eclipse for the last time,” said NASA scientist Richard Vondrak in 2017.

In terms of physical size, the Sun is indeed 400 times larger. However, its distance from Earth is also 400 times greater than the distance from the Earth to the Moon.

Meanwhile, the apparent size of the Moon in the sky has also been reported to be continuously shrinking. Four billion years ago, it appeared far larger from Earth. In fact, before it settled into its current orbit, its apparent surface size could have been up to three times larger than what is seen today.