Why is the moon so red? Tonight's blood moon lunar eclipse explained

As soon as the moon rises from behind the horizon, it will be darker and redder than usual

Andrew Griffin
Friday 27 July 2018 16:36
Comments
Blood Moon 2018: the longest lunar eclipse of the century

If you're out tonight, look up: you might catch sight of the blood moon, and some other sights besides.

Unless the rain is ruining it, the UK is preparing for a lunar eclipse, during which the moon will turn a deep, bloody red and go much darker than usual.

And this one is extra special, marking a potentially once-in-a-lifetime experience: there won't be a lunar eclipse this long this century.

But why does the moon look so strange and red? It's all about light and location.

Why does it happen?

A eclipse happens when the Earth, Sun and Moon get in a line. In a lunar one, the Earth is in the middle – it sits between the Moon and the Sun and stops light getting between them.

The bloodiness comes as what light does get to the Moon makes its way around the Earth. As it does so, it is scattered, so that the longer wavelengths make it past the Earth and so are a deeper red.

It also means that the moon is much darker, because less light is getting to it.

When will it happen?

When the moon rises over the UK – at about 9pm – the lunar eclipse should be visible. But you might want to wait another hour or so until the sun has fully set and the sky is darker, which will allow you to see more of the dim disc of the moon.

Why is it called a 'blood moon'?

Because it's red, and looks faintly gory. There's nothing more to it than that.

But the name does appear to have encouraged the kinds of people – mostly British newspapers and YouTubers who identify themselves as pastors – who like to trick others into believing that there is something sinister or dangerous about the lunar eclipse. For that reason, some suggest the name should be dropped.

Register for free to continue reading

Registration is a free and easy way to support our truly independent journalism

By registering, you will also enjoy limited access to Premium articles, exclusive newsletters, commenting, and virtual events with our leading journalists

Please enter a valid email
Please enter a valid email
Must be at least 6 characters, include an upper and lower case character and a number
Must be at least 6 characters, include an upper and lower case character and a number
Must be at least 6 characters, include an upper and lower case character and a number
Please enter your first name
Special characters aren’t allowed
Please enter a name between 1 and 40 characters
Please enter your last name
Special characters aren’t allowed
Please enter a name between 1 and 40 characters
You must be over 18 years old to register
You must be over 18 years old to register
Opt-out-policy
You can opt-out at any time by signing in to your account to manage your preferences. Each email has a link to unsubscribe.

By clicking ‘Create my account’ you confirm that your data has been entered correctly and you have read and agree to our Terms of use, Cookie policy and Privacy notice.

This site is protected by reCAPTCHA and the Google Privacy policy and Terms of service apply.

Already have an account? sign in

By clicking ‘Register’ you confirm that your data has been entered correctly and you have read and agree to our Terms of use, Cookie policy and Privacy notice.

This site is protected by reCAPTCHA and the Google Privacy policy and Terms of service apply.

Register for free to continue reading

Registration is a free and easy way to support our truly independent journalism

By registering, you will also enjoy limited access to Premium articles, exclusive newsletters, commenting, and virtual events with our leading journalists

Already have an account? sign in

By clicking ‘Register’ you confirm that your data has been entered correctly and you have read and agree to our Terms of use, Cookie policy and Privacy notice.

This site is protected by reCAPTCHA and the Google Privacy policy and Terms of service apply.

Join our new commenting forum

Join thought-provoking conversations, follow other Independent readers and see their replies

Comments

Thank you for registering

Please refresh the page or navigate to another page on the site to be automatically logged inPlease refresh your browser to be logged in