Harvest moon 2020: when to see the October full moon from the UK - and meaning of its name
As we head into the month of October, the night skies are about to be lit up by a succession of bright, full-looking moons.
But only one of those moons will be a true full moon, and it just so happens that it’s the Harvest Moon too.
Here's everything you need to know.
What is a Harvest Moon?
In the Northern Hemisphere, the term ‘Harvest Moon’ is applied to the full moon which falls closest to the autumn equinox.
This year the autumn equinox – the moment when the sun is directly above the Earth’s equator and the day and night are of equal length – fell on September 22, so the full moon of 1 October is 2020’s Harvest Moon.
The name makes no difference to the appearance of the moon, which will retain its usual bright white appearance in the night sky.
It's possible you could notice an orange hue to the moon should you seek it out, but that effect is only to do with the moon’s proximity to the horizon.
Many people will be looking for the Harvest Moon just after sunset, when the moon will be much lower in the sky.
Any perceived orange colour is merely a trick of the light: when you look toward the horizon you’re looking through a greater thickness of Earth’s atmosphere.
Why is it called a Harvest Moon?
The moon rises about 50 minutes later each day, but its proximity to the autumn equinox means the time difference between successive moons becomes shortened to only about 25 to 30 minutes for several days before and after the full moon.
These moons also rise soon after sunset during or close to twilight hours, which can make it seem as though there are several full moons on successive nights.
The appearance of bright, full looking moons just after sunset meant that farmers working the fields in the days before tractors and electronic lights could take advantage of the moon’s light as they harvested their crop.
When can I see it?
The ‘true’ Harvest Moon will be visible on the night of Thursday 1 October, and technically, the moon won’t be at its ‘fullest’ until slightly after 10pm.
Of course, you won’t need any specialist equipment to see it (the full moon will be just as visible as it always is), although there is always a risk that cloud cover could scupper your lunar enjoyment.
Showers will be heaviest and most frequent in the southwest, with even a risk of hail and thunder.
What else is happening in the sky?
This year's Harvest Moon will be joined by Mars, the red planet which will appear very close to the moon in the night sky.
To see it, look for an object that looks like a bright, red star.
You shouldn’t miss it – the planet won’t be as bright again until 2035, and will appear even brighter than Jupiter, the largest planet in our Solar System.