Molybdenum, With Atomic Number 42, May Have Helped Life Begin on Earth

Posted on April 16, 2014

A release from NASA Jet Propulsion Laboratory (JPL) describes the "Water World" theory for the origin of life on Earth. Life began inside alkaline hydrothermal vents on the sea floor in this theory. Scientists theorize these vents "maintained an unbalanced state with respect to the surrounding ancient, acidic ocean." The vents "could have provided so-called free energy to drive the emergence of life." The theory was first hypothesized by scientist Michael Russell of JPL in 1989.

The vents would have created chemical imbalances involving a proton gradient and an electrical gradient. For life to begin in the ancient oceans enzymes also would have been needed to drive chemical reactions. Two mineral "engines," a mineral known as green rust and a rare metal called molybdenum were also involved. These minerals may have lined the walls of the chimney structures in the ancient underwater vents and could have triggered chemical reactions that produced organic compounds, the essential ingredients of life. Molybdenum has the atomic number of 42, which is a number well known to Douglas Adams fans. 42 is the answer to the ultimate question of life, the universe and everything in Adams' novel, The Hitchhiker's Guide to the Galaxy.

Russell says, "We call molybdenum the Douglas Adams element." He adds, "Forty-two may in fact be one answer to the ultimate question of life!"

Laurie Barge, second author of the study at JPL, says, "Michael Russell's theory originated 25 years ago and, in that time, JPL space missions have found strong evidence for liquid water oceans and rocky sea floors on Europa and Enceladus. We have learned much about the history of water on Mars, and soon we may find Earth-like planets around faraway stars. By testing this origin-of-life hypothesis in the lab at JPL, we may explain how life might have arisen on these other places in our solar system or beyond, and also get an idea of how to look for it."

Michael Russell and Laurie Barge of NASA's Jet Propulsion Laboratory, Pasadena, Calif., are pictured in their Icy Worlds laboratory in the photo below. A new research paper about the theory was published in the April issue of Astrobiology.

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