Northern Ireland will soon bear witness to the biggest full moon in recent memory, when a record-breaking ‘supermoon’ appears in the sky this month.
Supermoons are not particularly rare in themselves – the last three months of this year all boast one – but November’s will be the biggest for nearly 70 years. The last time one this big was seen was in 1948.
On November 14, our planet’s only natural satellite will appear 14 per cent larger and 30 per cent brighter in the night sky.
“The full moon of November 14 is not only the closest full moon of 2016, but also the closest full moon to date in the 21st century,” according to NASA.
What is a supermoon?
Of course, the moon itself is not actually growing in size, it is simply a result of the Moon’s elliptical orbit around our planet.
An egg-shaped path means that the Moon can be at different distances from the Earth depending on what stage of its orbit it is in. It can mean a difference of up to 30,000 miles, with the closest point called the perigee, and the furthest the apogee.
When the orbit of the moon lines with the sun and the Earth in a particular way, it causes an effect called perigee-syzygy, which essentially means the moon appears far bigger in the sky and becomes known as a supermoon.
When is the best time to see it?
On Monday, November 14, the supermoon will be lighting up the night sky for many hours. But for the best effect – and the closest you’ll get to witnessing the spectacular images seen across social media following such an event – you’ll want to look east shortly after sunset, which on November 14 falls at roughly 4.12pm.
According to NASA: “When the moon is near the horizon, it can look unnaturally large when viewed through trees, buildings, or other foreground objects. The effect is an optical illusion, but that fact doesn’t take away from the experience.”
By the time it is higher in the sky, the 14 per cent increase in its usual size will be harder to make out. Any budding photographers will also want to get their hands on a proper camera. The small lens on your smartphone won’t be able to make out the change in size.
When will be the next chance to see a supermoon?
Should inclement weather cloud up the sky as it so often does at this time of year, the next supermoon isn’t too far away. December 14 is when we will next be the next opportunity, although it will be nowhere near as impressive as November’s.
It is also something of a bittersweet supermoon, with the increased brightness of the full moon coinciding with the annual Geminids meteor shower. The excess light will wash out the night sky, making the spectacular shower much harder to view.
The next supermoon to come close to November’s record-breaker won’t be seen until 2034, although even then, it won’t be quite as large as this month’s.