The Yellowstone volcano in Wyoming, USA is North America's largest volcano system? It is often referred to as a "supervolcano" because it has spewed more than 1,000 cubic km of ash and lava in a single event. The most recent of these massive blasts occurred some 640,000 years ago.
Aurora
No matter what the weather UV rays can cause irreversible damage to your eyes. Sunglasses are more than a fashion accessory.
