TONIGHT a rare occurrence will take place in the skies over Sussex: a Harvest Moon appearing on Friday the 13th.

The Harvest Moon itself isn’t actually that rare – it happens every year and is just the name given to the full moon occurring at this time of the year.

But tonight’s Harvest Moon is being called a "micromoon" due to being about 14 per cent smaller in the sky than an average full moon.

It’s like the opposite of a supermoon. Maine Farmers’ Almanac astronomer Joe Rao said the reduced size is due to the position of the moon when it peaks.

He told the Express: "To add to this Full Moon ‘madness’, this upcoming Full Moon very nearly coincides with apogee – that point in its orbit which places it at its greatest distance from the Earth: 252,100 miles away.

"Remember last February, when the Full Moon coincided with perigee, its closest point to Earth? The Moon was more than 30,000 miles closer and was accordingly branded a ‘Supermoon’."

What’s more, having a full moon appear on the night of Friday 13th is also pretty rare.

The last time it happened was in the year 2000 and it won’t happen again until 2049.

Although, if we’re being technical, it’ll actually be on Saturday 14th as it’ll hit peak at about 5.30am BST.