Towns and cities create an orange glow on the horizon at night. It's so widespread that it even disturbs sea creatures.
We have transformed the night-time environment in a very short time, relative to evolutionary timescales. Most wildlife hasn't had time to adjust.
The spectacle of glowing dolphins should serve as a timely reminder of our need to conserve the darkness we have left.
We haven't heard anything from alien civilisations, but perhaps they've heard us.
Clownfish eggs exposed to artificial light completely fail to hatch, highlighting the growing problem of light pollution.
Turning street lights off at midnight could save money, energy and help nocturnal ecosystems thrive.
Whether you're a night owl or a morning lark, circadian rhythms control just about every aspect of your health.