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Nine out of this world facts about the Moon

Full moon, blue moon, harvest moon, crescent moon - there’s something romantic about the lovely Moon.

Here are some staggering facts about our benevolent protector in the night sky.

1. The Moon isn’t a sphere

The Moon’s egg-shaped. When you look at it, you are actually looking at one of the small ends. And it’s wonky - its centre of mass is not right in the geometric centre, it’s 1.2 miles off the centre.

2. We’re never seeing all of it

At any one time we are only seeing 59% of the Moon. The remaining 41% can never be seen from Earth. And if you don’t believe us, if you went up to space and stood on the hidden 41% you wouldn’t be able to see the Earth!

3. The Blue Moon was the result of a volcano

The term ‘blue moon’ is believed to have originated in 1883 after the eruption of Krakatoa. So much dust floated in the atmosphere that when you looked at it, the Moon looked blue. Obviously this was so unusual the phrase “once in a blue moon” indicates something that happens very rarely.

4. The Moon was almost blown up

The U.S. seriously contemplated detonating a nuclear weapon on the Moon. The idea was that this would be a show of strength that would allow the U.S. to flex its military muscle in front of the Russians and intimidate them into backing down. The secret project was named 'A Study of Lunar Research Flights’, or 'Project A119’.

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5. Eclipse caused by a dragon

An ancient Chinese belief dictates that a solar eclipse was caused by a dragon swallowing the sun. In response, they made as much noise as possible during an eclipse to frighten the dragon away. They also believed that a huge toad lived on the Moon, sitting in a crater. The Moon’s craters are actually caused by space rocks bashing into it around 4.1 billion years ago.

6. The Moon is slowing us down

When the Moon is closest to Earth, what’s called its perigee, spring tides are higher. These are called perigean spring tides. Some of the rotational energy of the Earth is stolen by the Moon, and that is causing Earth to slow down by around 1.5 milliseconds every century.

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7. The light of the Moon

The sun is 14 magnitudes brighter than the full moon. For a full moon to shine with the same brightness as the sun, you’d need 398,110 Moons. During a lunar eclipse when the Moon moves into the Earth's shadow, the surface temperature of the Moon can drop around 500 degrees Fahrenheit in less than 90 minutes.

8. Leonardo da Vinci realised what the crescent was

When the Moon appears as a crescent, what we’re seeing is sunlight illuminating a sliver of the Moon. The rest of the Moon is only very dimly visible depending on weather conditions. Leonardo da Vinci was the first recorded person to realise that the Moon was not shrinking and expanding, some of it was just hidden.

9. Naming the Moon

The International Astronomical Union names Moon craters, and all other astronomical objects. Moon craters are generally given the names of notable scientists, artists or explorers. The craters around the Apollo crater and the Mare Moscoviense are named after American astronauts and Russian cosmonauts.

There’s so much we don’t know about the Moon. But we know more than these people: in a survey conducted in 1988, 13% of those surveyed by the Lowell Observatory of Flagstaff, Arizona, believed that the Moon was made of cheese. In 1988. We’ll just leave that there.

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