Fuel cells could reveal how life arose on Earth

Researchers have found a unique way to study the origins of life

Fuel cells are found in specialized cars, planes and NASA's human spacecraft, such as the now-retired space shuttle.

Laurie Barge of NASA's Jet Propulsion Laboratory said that something about Earth led to life, and the think one important factor was that the planet provides electrical energy at the seafloor, asserting that this energy could have kick-started life - and could have sustained life after it arose.

Fuel cells are similar to biological cells in that electrons are also transferred to and from molecules. In both cases, this results in electricity and power. In order for a fuel cell to work, it needs fuel, such as hydrogen gas, along with electrodes and catalysts, which help transfer the electrons.

In the team's experiments, the fuel cell electrodes and catalysts are made of primitive geological material thought to have existed on early Earth. If this material can help transfer electrons, the researchers will observe an electrical current. By testing different types of materials, these fuel cell experiments allow the scientists to narrow in on the chemistry that might have taken place when life first arose on Earth.

The researchers also tested material from little lab-grown "chimneys," simulating the huge structures that grow from the hydrothermal vents that line ocean floors. These "chemical gardens" are possible locations for pre-life chemical reactions.

When the team used material from the lab-grown chimneys in the fuel cells, electrical currents were detected. Barge said that this is a preliminary test, showing that the hydrothermal chimneys formed on early Earth can transfer electrons-and therefore, may drive some of the first energetic reactions leading to metabolism.

The experiments also showed that the fuel cells can be used to test other materials from our ancient Earth. And if life did arise on other planets, those conditions can be tested, too.

The study has been published in the journal Astrobiology.