Staring at the full Moon, Joshua feels his skin begin to itch. Thick hair is spreading over his body. He feels a deep need to howl. "Oh no!" he thinks. "I am a werewolf!"

Scientists do not believe in werewolves. But some believe that the Moon does influence how we feel.

At the end of this week an asteroidA small body in space, made of metal and rock material. Asteroids usually orbit the sun, but if knocked off course they can be drawn into Earth's gravity and fall towards it. will go into orbit around Earth. But on 25 November it will start to move away again. Asteroids like this are called "mini-moons."

Sadly, we will not be able to see it. It is a fraction of the Moon's size, and it will be five times further away.¹

The Roman philosopher Pliny the ElderGaius Plinius Secundus (23 - 79AD), better known as Pliny the Elder, studied botany and philosophy in Ancient Rome and created the first known encyclopaedia. thought that the full Moon made dew heavier. This created extra moisture in the brain, which led to madness.

The term "lunatic" comes from the Latin word for the Moon. It was defined in the 1700s as someone who changes from sane to mad and back according to what the Moon is doing.²

Writing in Discover, Kate Golembiewski suggests a reason for this belief. Because our ancestors slept less well when the Moon was bright, tiredness sometimes made them behave oddly. A study in 2013 found that even in the 21^st Century people sleep on average for 20 minutes less during a full Moon.³

In the 1970s a psychiatristA doctor who specialises in diagnosing and treating mental illnesses. called Arnold Lieber argued that because around 70% of the human body is water, we are affected by the phases of the Moon in the same way as ocean tides are. He claimed that murders and suicides increased dramatically during a full Moon. 

Later studies have disagreed with this. A Finnish one even found that there were fewer murders.

But a few years ago another psychiatrist, Thomas Wehr, noticed a strange pattern among 17 of his patients. He found that with some the mood swings followed a 14.8-day cycle. Others followed a 13.7-day cycle. And these two cycles mirrored those of the ocean tides.⁴

Will it affect our mood?

Yes: Many extremely intelligent people through the ages have believed that heavenly bodies exert an influence over us, and Professor Wehr's findings cannot simply be put down to coincidence.

No: Even if we accept that our own Moon has an effect us, which is doubtful, this mini-moon is so small and will be so far away that it cannot possibly make any difference to anything.

Or... It might cheer us up. Most people get excited by celestial phenomena, from shooting stars to solar eclipses, and this could be a welcome distraction from our problems here on Earth.