The Extremely Cool Physics of the Moon

Jeff Bezos is desperate to go to the Moon. Elon Musk is heading for Mars. Who’s right? What will realistic engineering look like on the Moon and how will the unfamiliar physics affect life there?

It’s Going To Be A Long Night

It’s clear that solar panels will be a vital lunar power source but getting enough daylight might be an issue for future colonists. The result of millions of years of gravitational interaction between the Earth and the Moon is something called “tidal locking” or synchronous rotation. On Earth, tidal locking means everyone always sees the same face of the Moon. On the Moon, the effect is more significant: it means a single one of their days lasts nearly 30 Earth days. As a lunar colonist, once the sun sets over the horizon, you aren’t going to see it rise again for a fortnight. I like a lie-in, but even I might find 2 weeks excessive.

Did You Hear About the Party on The Moon?

Contrary to what you might read in your Christmas cracker, the Moon does have an atmosphere although it’s so thin it’s practically nonexistent. Most gas particles that do get captured by the lunar gravity get blown off again by the solar winds. Occasionally, water particles will stick and gradually migrate towards the poles where they form ice deposits. That’s another reason the poles are a good location for a base.

Weight Loss Programme

The Moon is about a quarter the size of Earth and only about 60% as dense. Gravity depends on mass, so the gravity on the Moon is a sixth that here. If I was 9 stones on Earth, I would only weigh 1.5 stones on the Moon! That’s useful in some ways but bad in others. Humans aren’t designed to weigh so little and in a low gravity environment our skeleton and muscles will grow weak. Astronauts have to work hard to keep their bones strong. Without resistance exercises they couldn’t safely return to the tougher gravity of Earth.


The Moon would be a cool place to visit, but it would be a pricey trip. Is there any stuff there that might be useful? Fortunately, there’s water (at the poles and also in moondust), oxygen in the form of minerals, and metals like iron and magnesium. For folk on Earth, it would be easier to get those things here than from the Moon. However, for people in space the Moon could be a useful source of materials that wouldn’t have to be lifted out of Earth’s gravity well.

The Future

If human society ever moves into space, the strategic location of the Moon and its resources will make it important. In my opinion, it’s a damn interesting place. Humanity should be there.

About the Author

As well as being an engineer for 25 years, Anne Currie is the author of a series of science fiction action and adventure novels that explore AI, surveillance, climate change and new forms of society.

Panopticon Series

SciFi author interested in tech, engineering, science, art, SF, economics, psychology, startups. Chaotic evil.

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