Friday the 13th and full moon collide: should we be afraid?

A full moon photographed in London

Selenophobics and friggatriskaidekaphobics will be quivering at the thought, but travellers are in luck

LAST UPDATED AT 14:12 ON Fri 13 Jun 2014

For the first time in fourteen years, a full moon will fall on Friday the 13th – a double whammy for the superstitious. Selenophobics, who fear the moon, and friggatriskaidekaphobics, who fear Friday the 13th, might want to stay at home as the two Western superstitions coincide – an event that last occurred on 13 October 2000 and will not happen again until 13 August 2049. 

So why is Friday the 13th seen as unlucky?

Friday is traditionally considered an unlucky day and 13 an unlucky number. In numerology, 13 is deemed an "irregular number" and is the number of witches you need to form a coven. It also dates back to a Nordic myth in which 12 gods hold a dinner party at Valhalla. The 13th guest is Loki, the god of mischief, who arranges for the god of joy and gladness to be killed. In the Bible, Judas was supposedly the 13th guest to sit down at the last supper, and Jesus was believed to have been crucified on a Friday. In Canterbury Tales, Chaucer also references Friday as being an unlucky day: "And on a Friday fell all this mischance." It was also historically known as the day that people were hanged in Britain. As a result of the superstitions arising from these beliefs, many passenger airlines do not have a row 13 and many hotels will often skip floor 13 to appease nervous customers.

What about the full moon?

Some people believe that the moon influences human and animal behaviour in the same way in which if affects the tide, through gravitational pull. Others believe the extra light causes strange changes on the planet. Police officers and staff in hospital emergency departments often say that there are more accidents and violent incidents during a full moon. Some police forces have even deployed extra officers on nights when the moon is full after seeing an increase in violent offences. This year also coincides with the World Cup and one of the hottest days of the year so far, two factors that have previously led to an increase in crime rates for certain offences.

Is Friday the 13th actually unlucky?

The Daily Mail points to analysis of ten years' worth of data from car insurer Aviva, which says car accident claims increased by an average of – you guessed it – 13 per cent on Friday 13th, compared to other days in the same month. However, other studies suggest fewer accidents and fires occur because people take more care on Friday the 13th, says The Independent. But Dr Caroline Watt, from the University of Edinburgh's department of psychology, has said that holding such superstitions could prove the greatest risk. "If people believe in the superstition of Friday the 13th then they believe they are in greater danger on that day. As a result they may be more anxious and distracted and this could lead to accidents. It becomes a self-fulfilling prophecy." Historian Donald Dossey once told the National Geographic that Friday the 13th costs the American economy approximately $800-$900 million because people are afraid to fly and do the business that they would normally carry out. But on the plus side, the Daily Telegraph notes that Friday the 13th is therefore the cheapest day to fly. Today is the only Friday the 13th of the year but – luckily for non-superstitious travellers – there are three in 2015. · 

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