At 7.08pm on the 19th, the Moon comes within 356,575km of Earth, more than 30,000km closer than its mean distance from Earth, which is about 384,400km.
If the sky is clear, we’re in for an exceptionally big and bright full Moon and, because of the Moon illusion, it will appear particularly large as it is rising. The following high and low tides will be higher and lower than normal, too.
The Moon’s orbit around the Earth is an ellipse, 5.5 per cent off being a perfect circle, so its distance from Earth is always varying. There’s a maximum and a minimum distance during each lunar month – the time from one full Moon to another. The closest point to Earth in its orbit each month is known as perigee.
Sometimes other factors combine to make one perigee a bit closer than usual and on 19 March, all those factors reach a maximum almost simultaneously so that this one will be unusually close.
While they are eye-catching, close approaches of the Moon are not unusual. The Moon came within 356,566km on 12 December 2008, and there will be another close perigee on 26 October this year, when the Moon will come within 357,052km. On 14 November 2016 the Moon will come within 356,509km of Earth.
So although the phases of the Moon are likely to be marked on your calendar, you may want to make a note that this one will be pretty spectacular.