Rosaly Lopes can recall the exact moment when she decided to become a volcanologist. “During my college days, I was taking this class—Geology of the Earth and the Planets—and one day the professor did not show up,” she explains. Eventually someone announced to the class that Mount Etna had erupted and the professor was on his way to Sicily to study it. “The volcano erupts and the professor has to go? That’s what I want to do,” she recalls, smiling from ear to ear. From that moment forward, Lopes knew which career path she would follow, even if it was covered with 2,000-degree Fahrenheit lava. Since then, she’s been to active volcanoes on all seven continents, including Mount Erebus in Antarctica.