Skywatchers are gearing up for a lunar eclipse, which some are referring to as a "super blood wolf moon".
During the spectacular event, the Earth's natural satellite turns a striking shade of red.
The entire eclipse will be visible from North and South America, as well as parts of western Europe (including the UK) and north Africa.
What is a total lunar eclipse?
This kind of eclipse occurs when the Earth passes precisely between the Sun and the Moon.
In this situation, the Sun is behind the Earth, and the Moon moves into the Earth's shadow.
Will the moon appear red?
Yes. Some commentators are referring to the event as a "super blood wolf moon". The "super" part comes from the fact that the Moon will be near its closest approach to the Earth - when it will be marginally bigger in the sky than usual. The "wolf" part comes from the name given to full moons in January - "wolf moons".
Walter Freeman, an assistant teaching professor at Syracuse University in New York state, said: "A little bit of sunlight is refracted by the Earth's atmosphere and reaches the Moon, bending around the edges of the Earth. This small amount of red light still illuminates the Moon enough for us to see it."
Where and when can I see it?
The eclipse begins at 02:35 GMT on Monday and ends at 07:49 GMT, but the period when the whole Moon appears red occurs at 05:12 GMT.
In the UK, the Moon will be above the horizon throughout the eclipse, though from the extreme south-east of England the Sun will have risen as it comes to an end.
This eclipse will also be visible in north-western France, north-western Spain, Portugal, a small part of west Africa, almost the whole of North and South America, the eastern Pacific, and the north-eastern tip of Russia.
Is it safe to look at?
While solar eclipses are dangerous to view directly, the light from lunar eclipses is much fainter and so is completely safe to view without special equipment.
Why is it significant?
The event is the last chance for skywatchers in the UK to see a total lunar eclipse in its entirety until 2029 - weather permitting.