Iliamna Volcano, Alaska Photograph by Michael Melford, National GeographicClouds scrape by the snow-covered Iliamna Volcano, which last erupted before Europeans settled in the area. Download Wallpaper (1600 x 1200 pixels)
Flash and Ash Photograph by Sigurdur Hrafn Stefnisson, National GeographicLightning pierces the erupting Eyjafjallajökull volcano’s ash cloud in spring 2010. (See more pictures of lightning at Eyjafjallajökull volcano.) While exploring Thrihnukagigur’s interior might not shed much light on why Eyjafjallajökull erupted so violently in 2010, the knowledge gained from the expedition could help scientists understand volcanoes in general, scientists say. “It could help us understand the plumbing systems in volcanoes,” Sigurdsson said, “how the magma moves around, … the conduits that magma travels along, and what it leaves behind when it’s finished.” ON TV: Into Iceland’s Volcano airs Friday, April 8, at 8 p.m. ET/PT on the National Geographic Channel. Preview »