New research reveals how flying exposes us to cosmic rays. It's time we were aware of the risks.
The greatest ozone-depleted area in the world beside the one over Antarctica runs along the Peruvian Andes.
Greenpeace tests show overall contamination from key isotopes has fallen somewhat, but lingers, especially in places such as forests.
A 54 centimeter robot with a scorpion-like tail will be sent inside one of Fukushima's reactors this August.