The Moon is about to go dark as it is covered by a lunar eclipse.
As the Earth, Sun and Moon line up to create the rare celestial spectacular, their timing is perfect: it comes exactly 50 years to the day since the beginning of the Apollo 11 mission, when astronauts set off for its surface.
The partial eclipse will be visible across the UK, much of Asia, all of Africa, the eastern part of South America and the western part of Australia.
It will appear in the sky on the evening of 16 July. That happens to be the exact same date that the Apollo 11 mission to the moon blasted off, with the first people ever to touch the lunar surface arriving just a few minutes later.
A lunar eclipse happens when the Earth, Sun and Moon all line up, leaving the Moon hidden from the Sun by the Earth, which sits in between the two. As the Moon moves into the shadow the Earth, it dims dramatically.
What light does fall on it comes from around the Earth's atmosphere, meaning that it is given a deep red tinge. It is that leads some to call the event a "blood moon", because of its rich colour.
In the UK, the Moon will rise shortly after it has entered into the darkest part of the Earth's shadow, meaning that it will already be eclipsed when it becomes visible. It will come up around 9pm in London, and will arrive later the further north and west it is seen from.
The sun does not set until shortly after, so it will rise up into a brighter sky. The eclipse will be visible for hours after, however, giving people the chance to see it as the sun sets and the surface of the Moon changes in appearance.