The Night the Moon Turned Red

Posted 30th September 2015

There are some nights when I wish I could get back to sleep but this wasn’t one of them. I didn’t want to shut my eyes!

Staring out of the window up to the night sky, I couldn’t take my eyes off it, as I witnessed the moment the Moon, Earth and Sun lined up to create a spectacular lunar eclipse.

I’m a little bit in love with the Moon anyway, there is something so magical about it as it casts its glow upon the Earth amidst the darkness.

But there was something even more special about the Moon that night…

… Colour!

For as the Earth cast it’s shadow across the powerful, bright glow of the night’s full Moon, the total lunar eclipse created a stunning fiery, rusty red glow!

Supermoon Lunar Eclipse

 A perigee full Moon, or supermoon during a total lunar eclipse on Sunday, September 27, 2015 (Image from NASA)


Curious, I did a bit of research to find out why the Moon turned red and was soon reminded of one of my favourite projects from my time at Uni – the incredible power of colour!

You see, colour is so much more than something that we perceive…

Colour is light

Colour is not on the surface, but is actually light that is reflected off a surface back to our eyes. It is then interpreted by the brain as colour, creating the image that we see.

So while we talk about the Moon’s glow, the Moon doesn’t emit light, it reflects it. When we see the Moon glowing brightly in the night sky, this is the light of the sun directly shining upon the Moon’s surface and reflecting back at us as lightwaves that our brain then interprets, usually as white.

Light is energy

Light is energy that travels in waves. Light from the Sun is made up of a spectrum of waves which, if we think back to our science lessons of passing light through a prism to break it up, is a series of colours, violet and blue through to red and those in between. Lightwaves, as the name suggests, are waves of energy that have a frequency. On the one end of the spectrum is blue made up of shorter waves and on the other end red, which has the longest waves.

Dispersion of white light by a prism into a spectrum

Dispersion of white light by a prism into a spectrum (Image from BBC Bitesize)


How do we see colour?

So when we see the Moon glowing white in the sky, what we are actually seeing is ALL of the light waves reflecting back off its surface. When we see something green, all the other lightwaves get absorbed by the surface and only the green lightwaves reflect back to us, therefore seeing green. A red object only reflects red lightwaves and so on… And an object that appears black is actually absorbing all the lightwaves and reflecting back none.

So why did the moon turn red?

As the Earth cast its shadow upon the Moon, while the Earth itself may have blocked out sunlight from reaching the Moon, the Moon didn’t disappear as we might expect. Instead, because the Earth has an atmosphere, made up of dust, glass, water etc, some of the sunlight passing around the Earth passed through this atmosphere. While doing so, some of it was reflected off these particles, or was absorbed by them and the spectrum of light scattered. Without getting too technical – remember I am a designer not a NASA scientist –  the shorter light waves at the blue end of the spectrum were either reflected away or absorbed. This is why in the day time the sky appears blue, as we see the blue lightwaves reflecting off these particles.

The longer wavelengths, reds and oranges etc, continued to pass through the atmosphere less affected, which were refracted/bent through the atmosphere to reach the Moon. As these were the only lightwaves reaching the Moons surface, they were the only lightwaves reflected back to us, and therefore the colour we saw, that incredible rusty red.

Lunar_eclipse_sideview_v01 The Sun, Earth and Moon aligned during a lunar eclipse, showing the red lightwaves reflected off the Earths atmosphere onto the Moon (Image from NASA) 


There is so much more to colour that I will share with you soon, including how different colours have their own energies and can affect our mood, appetite and even our blood pressure – it’s fascinating!

While I was eager to catch a glimpse of the “rusty” red Moon just to say I had seen it, I never could have guessed the effect it would have upon me. That night, as I watched in awe the Moon turn red,  my mind was flooded with positive inspiration. Maybe it was the fascination of watching such a rare phenomenon, maybe it was the impact of the red energy, whatever it may have been, I have since been empowered by a renewed sense of motivation and purpose.

So, next time you look at the Moon, remember, what you are seeing isn’t a colour – it is energy!

Skellig Moon by Norman McCloskey

A full moon sets over the Skellig Rocks off the coast of Kerry in Ireland 26th April 2013 (Image © Norman McCloskey)