The biggest supermoon of 2018 is expected to light up the sky on New Year’s Day and bring extra high tides to Cornwall over the next few days.

The ‘Wolf Moon’ is the second in a ‘supermoon trilogy’ which started with the ‘Cold Moon’, spotted above Cornwall on December 3.

It will be swiftly followed by the ‘Blue Moon’ on January 31 – so-called because it’s a rare time when two full moons appear in the same calendar month.

The first supermoon of the year – also know as the ‘Old Moon’ – will peak overnight on January 1, in a chance alignment of the lunar and calendar cycle.

It rises at sunset and sets at sunrise and will be the largest and brightest full moon of 2018. It will also bring extra high tides to Cornwall.

Early Native American tribes named the first full moon of the year after the wolf, as this was the time of year when packs of the animal would howl outside their camps.

What is a supermoon?

A supermoon occurs when a full moon coincides with the moon reaching perigee, which is the point of the orbit where the moon is closest to Earth.

The point farthest from Earth is known as apogee.

Beautiful photograph of a supermoon

Full moons appear around 14 per cent larger and 30 per cent brighter when the phenomenon occurs, according to NASA.

The changes are hard to spot with the naked eye when the moon is high in the sky, but can cause dramatic impact as the moon rises or sets in the sky.

When is the New Year’s Day supermoon visible?

The first full moon in 2018, which will be the biggest and closest supermoon of 2018, will occur on the night between January 1 and 2.

It will peak at 2.24am GMT, the Royal Observatory in Greenwich said, as this is when the moon will be perfectly lit up by the sun.

But stargazers won’t need to stay up this late to catch the phenomenon, experts said.

The difference in illumination between the evening and early hours is marginal, so there should still be a good light show on January 1.

When is the blue moon?

There will be a second supermoon on January 31, which can be considered a blue moon.

This supermoon is cited to be “extra special” as it will feature a total lunar eclipse viewable from North America across the Pacific to Eastern Asia.

A full moon becomes a blue moon when it is the second full moon to appear within the same month.

A spectacular full moon over Cornwall (Image: Greg Martin)

Blue moons happen every two and a half years, on average.

The moon won’t actually change its colour to blue, but those in North America, Asia and Australia may witness it turn red as it coincides with a lunar eclipse.