EDITOR’S NOTE: Call to Earth is a CNN editorial series committed to reporting on the environmental challenges facing our planet, together with the solutions. Rolex’s Perpetual Planet Initiative has ...

Skywatchers will use the period between Saturday, April 15 and Saturday, April 22 to ensure that policymakers aren’t in the dark about the problem facing our view of space. When you purchase through ...

For most of human history, the stars blazed in an otherwise dark night sky. But starting around the Industrial Revolution, as artificial light increasingly lit cities and towns at night, the stars ...

As dawn rose over the German city of Bremen on May 7 1823, Heinrich Olbers put the finishing touches to an article that left his name in history. After the deaths of his wife and daughter, Dr Olbers ...