Physician letting blood from a patient. Attributed to Aldobrandino of Siena: Li Livres dou Santé. France, late 13th Century.
British Library, London, UK
A handful of manuscripts remain which give researchers valuable insights into medieval science.
Moths flutter toward light at night, but why?
Moths and insects cluster around lights at night. Why?
Dark sky sites can inspire new generations of stargazers, but a better long-term solution would be connecting people with the night sky where they live.
We haven't heard anything from alien civilisations, but perhaps they've heard us.
Some 22% of the worlds’ coastlines are exposed to artificial light at night.
Clownfish eggs exposed to artificial light completely fail to hatch, highlighting the growing problem of light pollution.
The panel of 60 Starlink satellites just before they were released to go into orbit around Earth.
Official SpaceX Photos
The first 60 satellites from Elon Musk's planned low orbit internet network have lit up the skies. But with more planned, astronomers say the satellites could ruin their work.
Light pollution comes with numerous problems.
Artificial light - including at the Tribute in Light in New York City - disorients nocturnal migratory birds.
Artificial light, from low-level backyard lighting to lights in office buildings and skyscrapers, distract migratory birds with deadly effects.
There's mounting evidence that increased lighting has a range of negative effects.
Cities today are flooded with light and we seldom think of its harmful impacts on the natural world.
Urban greening programs need to consider the harmful impacts of artificial lighting on ecosystems. Fortunately, we can do a lot to create more biosensitive lighting.
Cities are bright underwater too.
Sydney image from www.shutterstock.com
Light pollution is changing the day-night cycle of some fish, dramatically affecting their feeding behaviour.
World map of artificial sky brightness.
F. Falchi, et al. Science Advances (2016)
Eighty percent of North Americans can no longer see the Milky Way at night. But the problem with light pollution isn't just about stargazing.
The Dreamtime constellation of The Emu rises out of the glow of Sydney, 350km away from the Australian Astronomical Observatory.
Darkness is precious to astronomers, but it's also good for everybody. We should ensure we preserve the dark by using the latest technologies responsibly.
Artificial light can confuse these baby salmon.
Light is among the fastest growing human-made pollutants of the natural environment. Numbers of outdoor lights are growing rapidly across the world, far outpacing general population growth. We know light…
Big lights not inspiring nature.
Seattle Municipal Archives
Satellite images of the earth provide a striking picture of our planet during the hours of darkness. From space, the world at night appears as an intricate mass of tiny points of light, clustered into…
It’s easy to find your way home at night. From space.
Britain is a nation of birders. Thanks to TV shows such as the BBC’s Springwatch, bird feeding and watching is more popular than ever. More than half the UK adult population goes to feed the birds at least…