most courageous scientist ever

History is full of scientists who are heroes: savers of lives, solvers of mysteries, builders of the future. They are, however, a pretty nerdy lot, achieving great feats of the mind like wrestling with mathematical equations, dismembering molecules and exploding paradigms, but rarely performing physical acts of courage and strength. Then there is Ken Sims, volcanologist from the University of Wyoming:

"He didn't have a hammer, so with a hard slam of his fist he broke off a piece of fresh lava. It was shiny, iridescent black, and so hot that, even wearing thermal gloves, he juggled it from hand to hand.

But he had it. The zero-age sample. Through a war zone, up a mountain, down a crater, to the edge of a lava lake, he had it. Now the science, at long last, could begin."

Read the whole shoe-melting tale of Congo's Nyiragongo volcano at National Geographic.