Photographers from around the world have captured stunning images of the moon on the night before it is due to be at its biggest and brightest for almost 70 years.
Astronomers say that the moon will be so close to Earth on 14 November – just 221,525 miles – that it will appear to be up to 30% brighter and 14% bigger than average.
The time to see it at its biggest and brightest in the UK will be around 4.45pm, when it begins to rise and is nearest to the horizon.
If you miss the spectacle, it should still appear bigger than usual on Tuesday evening but will be a fraction smaller.
There is another ‘supermoon’ on 14 December, but if you fail to see that you will have to wait until 25 November 2034, according to NASA.
Robin Scagell, vice-president of the Society for Popular Astronomy, explained why the moon appears to change size and brightness.
He said: “The moon’s distance from Earth varies because it has an elliptical rather than circular orbit, as do all planetary and satellite orbits.
“If the Earth and moon were the only objects in the universe and we were totally flexible and solid, every closest point (perigee) and every farthest point (apogee) would be identical for eternity.
“But in the real universe, there are many more forces acting on the two bodies, notably the direction of the sun, so the perigee and apogee distances change slightly.”
Plans for a supermoon sighting may yet be scuppered by the weather, however, with forecasters predicting that most of the country will be covered in cloud.