Eyjafjallajökull’s eruption may be a hassle if you had any transatlantic flights planned this summer. For scientists, however, volcanic eruptions are the only way they can obtain samples from deep within the Earth to learn more about our planet, its formation, and its ongoing evolution. How long will this eruption last? How does it compare to other volcanoes around the world and throughout history? Smithsonian Geologist Liz Cottrell helps put this recent eruption into perspective.