Charles Langmuir, Harvard professor of geochemistry, loves going to sea. “It’s tremendously stimulating, wonderful, exciting, and eye-opening,” he says enthusiastically. “Every time I’ve gone since 1984, I’ve seen things I’ve never seen before. Sometimes, they’re things nobody has ever seen before. Teams of people keep the work going seven days a week, 24 hours a day. Their level of output and discovery is unmatched by anything that takes place in laboratories on land. There are no committee meetings; you don’t have to drive anywhere. The sunrises, sunsets, and star-filled nights are fabulous, so are the animals you see, from jellyfish to whales.” Langmuir has explored volcanic ridges and rifts on the floors of four oceans. In 1993, he was chief scientist on an expedition that discovered the largest field of hot springs on the bottom of the Atlantic Ocean, south of the Azores Islands in 5,000 feet of water. He went down in a deep-diving submersible called Alvin to look at the rocks and strange creatures firsthand. The sponges, worms, clams, and insectlike crustaceans never see sunlight and eat bacteria and each other, rather than plants. Langmuir wants to understand more about the interactions between the geologic processes that shape the planet, the atmosphere that envelops it, and the creatures that live on it. “We see ourselves as being on Earth to exploit the planet’s resources rather than as being an integral part of its natural evolution. Is intelligent life ultimately what a successful planet does? It’s common sense to see life as a natural part of planetary evolution, not only in the solar system but throughout the universe.”