The Sky: Humanity's Greatest Canvas

The skies above St Andrews are more than just beautiful — they are a spectacle. What the weather throws at us in wind and rain, the heavens repay tenfold in colour. 

St Andrews sits perched on the coast, looking out over the vast expanse of the North Sea. With almost nothing to block the view, our town gets a front row seat to Mother Nature’s nightly masterpiece.

For these splashes of colour in the sky, however, a list of criteria must be met. 

A scattering of clouds helps significantly amp up the visual display.  As the sun dips, its rays strike the underside of the cloud, refracting the light into a riot of colours.

Latitude — the real festival is our location: St Andrews is northerly on the planet (though our Scandinavian friends amongst us may beg to differ) and this location gives a shallower angle to the horizon, creating a technicolour dreamcoat in the sky.

The brilliance of darkness: St Andrews may have a big heart, but it is still a tiny place — a major win for the sky. Less light pollution means seeing the colours of the natural spectrum more.

When these factors combine, St Andrews witnesses incredible sunsets and sunrises. The only problem is that such beautiful skies are rare.

The question arises: can we control the colour of the sky? 

All would agree that a sunrise followed by vivid blue hues would make even a 9am a little more uplifting.

Well, we are in luck. There are a couple of ways that this can be done. 

Perhaps whilst at a concert, festival, or even at our golf range, you have noticed the sky illuminated, even if just a limited zone. This process can be taken, expanded, and, through clever technology, taken to the next level. High-power LEDs can generate light by pushing huge amounts of current through semiconductor layers. That current releases energy in the form of photons; this is electroluminescence. By scaling this, you can feasibly change the tint of the entire sky. Anything from a glowing orange sunset to a bright green morning would be possible.

You have most likely heard of aerosols; many contribute to polluting our atmosphere, but some can actually be beneficial..  It is these ‘good’ aerosols that can be creatively harnessed to change the sky. Tiny particles such as dust, ash, and even smoke interact with air particles to scatter light:  smaller particles scatter blue light, and the larger ones yellow. By effectively controlling the concentrations, using precise aerosols and lab conditions, it is possible to change the sky or, at the moment, the atmosphere of a room. Scale this process up, and overcast days could be a thing of the past. 

The coolest way, and of course, the most complex, is by the use of lasers. At any given moment, our atmosphere has many millions of particles merely floating around. If targeted with lasers, they emit light via laser-induced fluorescence. Hitting specific particles, in order, could fill the sky with whatever colour and pattern desired. By improving the quality and size of these lasers, the magnitude of the sky affected would increase. 

The upsides of this are nearly limitless. Birds and animals use light and colour to navigate these natural cues to guide them. Changes in the atmosphere and environment can disrupt this colour, making navigation more difficult for wildlife. Now we can do something to help.

Therefore, the sky’s colours are more than just a pretty phenomenon; they are vital. They guide, warn, and connect species to their environment. By understanding and carefully influencing these hues, we can do a great number of helpful things. So next time you look out on one of nature’s most beautiful gifts, ask yourself, what if we could make it not just beautiful but better for us and the world around us?

Image by Wikimedia Commons