A Full Blue Moon Will Light The Midnight Sky This Halloween

This Halloween promises to be the spookiest in almost 20 years as there will be a rare blue moon lighting up the evening sky as excited kids across the country head out trick-or-treating. Then later in the night, paranormal investigators will be able to hunt ghosts in the moonlight as the moon reaches its highest point in the sky at midnight.

Halloween conjures up images of ghosts, zombies, witches and bats, often set in front of a bright full moon, but for many of us 2020 will be the first year in our lifetimes when theres actually been a full moon on All Hallows' Eve.

The full moon will actually occur around 3pm GMT on Saturday October 31, 2020, obviously this is during daylight hours and here in the UK, the moon will be below the horizon at this point in the day - but it will be visible in other parts of the world.

At around 5pm the moon will rise again and climb in the sky, reaching its highest point in the night sky a few minutes after midnight. Although not technically a full moon any more, it will be at 99.8% illumination, so it will still appear full in the sky.

The reason the Halloween full moon is so rare is because it's a blue moon. This doesn't mean the moon will actually change colour or appearance. We get one full moon a month, but on rare occasions there are two full moons in a month, the rare second one is called the blue moon. There will actually be 13 full moons this year.

If there's a full moon on Halloween, then it is always a Blue Moon since October is a long 31-day month and the lunar cycle isn't perfectly synched to the calendar. You've probably heard the phrase "once in a Blue Moon," which already gives you a clue that a full moon on Halloween must be rare.

A Blue Moon only happens roughly every three years, but the chance that the month it occurs in is October is even slimmer. Although a bright full moon has become a spooky image that's commonly associated with Halloween, there's actually only been a handful of full moons that coincide with Halloween in the last 100 years. The last one in the UK was 1974, and in 2001 for the Central and Pacific time zones of North America.

However, there hasn't been a full moon on Halloween for everyone around the world in all time zones since 1944.

The first full moon in the month will be on October 1, the full moon traditionally called the Harvest Moon. The one on All Hallows' Eve is technically called a full Halloween Hunter’s Blue Moon.

So what does all this mean for Halloween? Will things be creepier? Will the dead rise from their graves and the air fill with the howls of werewolves transforming?

Full moons have historically been blamed for everything from an increase in odd human behaviour, unusual changes in the animal world. Some think that this could be as a result of the brighter than normal light from the Moon keeping people awake and confusing animals. This could lead to sleep deprivation that prompts irrational behaviour. Full moons have also been linked with an increase in paranormal activity.