A rare Blue Moon will light up UK skies this weekend - here's how to spot it

20 August 2021, 10:48

Here's how you can see the Blue Moon this weekend
Here's how you can see the Blue Moon this weekend. Picture: Alamy/Getty Images

When can you spot the rare Blue Moon on Saturday and Sunday? Here’s what you need to know…

It’s good news for stargazers, as a beautiful Blue Moon is set to light up the skies this weekend.

The last time we saw the phenomenon was back in Halloween last year and it has actually come a little bit earlier than expected.

But what is a Blue Moon and how can I see it? Find out everything…

A Blue Moon will be visible this weekend
A Blue Moon will be visible this weekend. Picture: Alamy

How can I see the Blue Moon this weekend?

You will be able to see the Blue Moon on both Saturday 21 and Sunday 22 August.

It will be visible in the UK on Saturday during the moonrise at around 8:22 pm and at around 8:45 pm on Sunday.

This will be the third full moon of the summer season.

What is a Blue Moon?

Despite its name, Blue Moon’s are actually not blue in colour, and instead display orange colours.

It will then appear as a bright, white colour.

According to Forbes, it will appear orange because the oxygen and nitrogen molecules in Earth’s atmosphere are narrower than the wavelength of red light, so red light passes through while blue light doesn’t.

They say: “Colours in the sun's light with short wavelengths, such as blue, strike more particles and are therefore more often absorbed.

"They scatter more easily, which is why the sky is blue during the day. Colours with longer wavelengths, such orange, more easily pass through the atmosphere uninhibited”.

“When you look at moonrise you're looking across the planet so you’re looking through a lot of atmosphere”.

The term ‘Blue Moon’ is thought to have originated from the fact that smoke and ash from volcanic eruptions cause the moon to go blue.

It's very rare that the moon would actually look blue, as Nasa explains: “Most Blue Moons look pale grey and white, indistinguishable from any other moon you've ever seen.

“However, be aware that on rare occasions it can happen”.