These pop up all the time, the moon has been just a little bit important in human history and we’ve had lots of time to tell myths about it. It would be nice to think that as a group we’ve grown out of werewolves and love spells, except we’re still doing it. There are new moon myths, given a modern spin with a bit of astronomy or biology, that are being spread around you right now, you possibly believe some of them yourself.
The moon has an affinity with water
Usually paired with the fact that people are 70% water, therefore the moon has a magical effect on us.
No. It just doesn’t.
This one obviously comes from the tides. The theory goes that if the moon is pulling water up towards it, then it must have an affinity sort of like a magnet with metal. In reality, water just moves easily because it’s a fairly light liquid.
The moon is very large and has a gravitational pull on the earth. It pulls whatever it happens to be above up towards it, whether that’s water or rock. There are land tides just like ocean tides, but they are so small they aren’t as noticeable. A couple of thought experiments tells you why.
First, think of balancing a bucket of water against a bucket of rocks. Gravity works on masses, and a given mass of rocks will be much, much smaller than the same mass of water. So less land moves than water for the same gravitational pull – it’s not an affinity with water, it’s just lighter than rocks.
Secondly, imagine lying underneath a balanced paddling pool and pushing up – you can easily make a large lump of water in the middle that sloshes out to the edges. Congratulations, you just modelled an ocean tide. Now imagine lying underneath a large, balanced slab of rock and pushing up on it. How much does it move? That’s an earth tide.
There is no affinity with water. The moon pulls on all of earth equally, it’s just that water is lighter and moves more easily than rocks. You may be 70% water but you aren’t about to go floating into the air any time soon.
The Full Moon
This one gets mixed up with the last one, in some giant mishmash of water and light and tides and it just affects us.
Firstly, there is a relationship between the full moon and the tides. But there’s also a relationship between the new moon and tides, and people don’t get all excited about that one. Basically when the earth, sun and moon all line up, which is full and new moon, there are larger tides because the gravitational influence of the sun and moon add up. When the moon is out to the side at the first and third quarter then they cancel out and tides are lower.
But, werewolves! Cops! Hospitals! Lunatics! Things happen at the full moon!
That’s not what the stats say. Epilepsy, psychiatric emergencies, emergency room visits, surgery, crime, homicides, dog bites, births and suicides have all been studied. There have occasionally been positive results, but on further examination they are either inconsistent or there are statistical errors. In short, the moon does not affect our behaviour.
So why do so many people think they do? There are probably a couple of different psychological effects at work here.
- Confirmation bias – we remember or notice things that agree with what we already think. You have a busy night at work, look up as you are leaving and see a half moon and promptly forget about it. You have a busy night at work, look up and see a full moon and see?! It justifies what you thought all along! Full moons are terrible! Or the opposite happens – you know it’s going to be a full moon so you notice every little detail that you would normally brush away, thus confirming that full moons are hard work, even if it was just a normal night.
- Isolation effect – we remember things that stick out. A full moon is very noticeable, so it is more likely to be seen and remembered than a half moon or cloudy skies.
- Timing – I don’t know if this has a name or is just statistics. The moon is only completely full for one night, but for a few days on either side it’s pretty close if you’re just glancing at it. Then add a few more days when it’s nearly full. You can easily end up with over a week when people will happily attribute strange happenings to ‘the full moon.’ But then you realise that the lunar cycle is only 4 weeks long, so ‘over a week’ is a fair chunk of it. The chances of a strange event falling within that time are pretty high – between 25 and 50%. Which makes the most likely thing that it was just co-incidence.
There are no werewolves. There are no lunatics. And if there ever was a reason for bad guys to be out during the full moon a little invention called electric street lighting got rid of it long ago. There’s only our own minds tricking us and wanting to believe in something out of the ordinary.
As far as I know this is the most recent of moon myths, only starting up a few years ago. It’s mainly a New Agey thing linked to the other ideas of the moon affecting us, as sometimes the moon is closer and brighter than normal, so it must have even more effect then!
The basis of it is true and has been known for a long time – the moon does get closer and further away. This is because it doesn’t orbit the earth in a perfect circle, but an oval. When it is closest to the earth it is called the perigee, furthest from the earth is called the apogee. Sometimes the full moon will line up with the perigee, roughly once a year. Astrologists and the media might call this a supermoon, astronomers do not.
It hasn’t been tied to any effects more than any other moon has – not at all. Remember the moon gets roughly this close to earth every month, even if it isn’t a noticeable full moon. And while there is a measurable difference in the appearance of the moon, as I pointed out the other day you probably won’t see it because we’re talking about millimetres.
Moon Landing Hoax
Just about every significant event in the last century seems to have attracted its own conspiracy theory, and the moon landing is no different. Every time an objection is answered another one seems to pop up, and there really isn’t a way to answer them – conspirators won’t take the word of the people who were actually there, and every film or photo can be dismissed as doctored by people determined not to believe.
But if you aren’t too far down the rabbit hole already there is plenty of evidence that NASA did reach the moon. My favourite starting point is Bad Astronomy, as you can see from the site design it’s old but it has been updated into a book and was the basis for the Mythbusters special. You may not trust the US government, but they didn’t fake the moon landings to put one over the Russians.
I like watching the moon, it’s pretty and my children like it. And I’m fascinated by what our modern myths and superstitions say about us – the way we think, how we construct knowledge and create patterns. Even how our distrust of particular groups plays out. Ultimately, I like that it reminds us that for all our technology, scratch the surface and we’re still the same as our ancestors who believed in magical spirits looking down on us.
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