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'Supermoon' lights up night sky

The moon is thought to look 16% bigger Photo: ITV News

The phenomenon of the perigee full moon, or the 'supermoon' as it is also known will grace the skies tonight, appearing in its biggest and brightest form this year.

It is also likely to cause higher tides as it reaches it closes point to earth. At this time it could appear up to 14 per cent larger and 30 per cent brighter than when it is farthest from the planet, experts said.

This YouTube video was taken in March 2011, when a similar phenomenon occurred.

But skywatchers will need a keen eye and clear weather to notice a significant difference - and they may have to stay up late. The Moon is expected to appear at its best in the early hours of tomorrow morning, at around 4.30am.

At this stage, it will be around 356,400 km away - compared to an average distance of around 384,000 km. Dr Robert Massey, of the Royal Astronomical Society said:

The eye is so good at compensating for changes in brightness that you simply don't notice (that element) so much. What you may notice is that the Moon will be a little bit bigger.

When the Moon is closest to the Earth and full or new, you get an increase in the tidal pull in the ocean because the gravity of the moon and the sun line up.

– Dr Robert Massey, of the Royal Astronomical Society

The moon's distance from Earth varies because it follows an elliptical orbit rather than a circular one.

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