50 Fun Facts About Every State in America

The Big Island's growing by more than 42 acres every year due to eruptions from the Kilauea volcano. Mauna Loa, one of the world's largest volcanoes, is on the Big Island as well. Astronauts once trained for moon voyages by walking on its hardened lava fields, and recently, six NASA-funded researchers spent months on the northern slope (pictured here!) simulating a Mars space station.