This week the UK's Public Astronomer, Marek Kukula
“If I rule the world I would replace old inefficient street lights all over the planet with modern efficient designs that only put the light where it is needed – down on the streets.
Instead of wasting it by shining it up into the sky where all it does is blot out the stars – that orange glow that mean city dwellers never see a dark sky.
Think of the difference that this would make. We would still have safe, well lit streets, but for the first time in decades people in towns and cities would be able to look up and see the wonder of the night sky. And it would not just would-be stargazers that would benefit. Less wasted light, means less waster electricity, less wasted money and a reduced carbon footprint.
Migrating birds and animals would also benefit – they would be able to navigate more easily using the moon and stars and there is even some benefit that human health would benefit from a more natural cycle of light and dark in urban areas.
So we would see many practical benefits and a natural wonder that should belong to everyone would be restored. I think this would make the world a better place because everyone would have a chance to see the stars and appreciate our place in the Universe.”
You can listen to Marek discuss his idea with American photographer Rachel Sussman and high-performance coach Rasmus Ankersen in more detail on the BBC World Service programme The Forum, where you can also download more 60-second ideas.