Early risers can enjoy one of the great free spectacles of the night sky on Thursday morning during the last "proper" total eclipse of the Moon for seven years.
If the skies are clear, anyone prepared to brave the early morning cold will see the Earth's shadow take a "bite" out of the Moon just after 1.40am.
At 3am, when the total eclipse gets underway, the Moon will turn to a blood red colour as it passes completely into shadow.
Although lunar eclipses take place around twice a year, this will be the last time that one can be seen in its entire majesty from everywhere in the UK until 2015.
Robert Massey, of the Royal Astronomical Society, said: "This is one of the great free events of astronomy because it's so stunning, and so easy to watch.
"I'd thoroughly recommend that everyone has a look if the skies are clear.
"You need to set the alarm clock, get up and brave the cold, but if it's clear, it's a really beautiful event and something quite special."
A lunar eclipse occurs when the Sun, Earth and Moon form a straight line in space and the full Moon passes through the Earth's shadow.
Unlike a solar eclipse - which needs special equipment and should not be viewed directly - you can watch a lunar eclipse with the naked eye.
The outer part of the Earth's shadow - called the penumbra - will fall onto the Moon around 12.40am, causing the lunar surface to darken slightly.
However, it is only when the Moon moves into the central, darkest part of the shadow - the umbra - at 1.43am that an obvious bite will appear on its edge.
Over the next 45 minutes, the bite will get larger and larger, until at 3am, it entirely covers the Moon.
At that point, the Moon will not vanish completely, but will change to an eerie, copper red disc.
The dramatic change of colour occurs because the only light to reach the surface of the Moon has passed through the Earth's atmosphere.
The atmosphere scatters blue light, but allows red light to pass through unaffected.
It is the same reason why the sun appears to turn red during a sunset - and the reason why the sky appears blue on a sunny day.
An eclipse of the Moon is nothing like as dramatic as a solar eclipse - but can still produce an astonishing spectacle.
"The colour can vary - it depends on how much dust and water vapour is in the Earth's atmosphere." said Mr Massey.
Although partial eclipses of the moon will be visible every year, the next time a total eclipse will be fully visible from Britain is September 28, 2015.
Britain will also get a partial solar eclipse - when the Moon passes in front of the Sun - on August 1.
However, the next total eclipse of the Sun is not due until 2081 from the Channel Islands and in 2090 from the South West of England.
Unlike a solar eclipse, each stage of a lunar eclipse is visible to everyone on the side of the Earth facing the moon.
Lunar eclipses have captured the imagination of people since the dawn of time.
In Ancient China they were regarded as an omen caused by a dragon devouring the Moon.
It was customary to bang pots and drums - and set off fireworks - to scare off the dragon.
HOW TO ENJOY THE TOTAL ECLIPSE
The eclipse will be visible from everywhere in the UK on Thursday morning, depending on the weather.
The Met Office is forecasting broken cloud for much of southern Britain - but cloud and rain in the north.
People are advised to stand away from street lights to get the best view.
The moon will start to dim just after 12.40am as it passes through outer part of the Earth shadow.
However, the true partial eclipse will not begin until at 1.43am when a "bite" will appear on the edge of the full moon.
The total eclipse begins at 3am and lasts for 52 minutes.
The Moon will remain visible, but should change colour to a deep blood red.
The partial eclipse ends at 5.09am.
It can be seen with the naked eye, although it will appear more dramatic through a pair of binoculars or telescope.
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