HOPES that we will find life on Mars have been dented by the claim that something is quickly destroying methane. This suggests conditions on the planet are much harsher than we thought.
In 2003, a telescope survey observed pockets of methane on Mars. This was a surprise, because the gas should have spread evenly around the planet, so Franck Lefevre and Fran莽ois Forget of the in Paris, France, created a climate model to explain how such concentrations might form.
The pair found that to recreate the observations, a big source of methane is required and the gas must be destroyed within 200 terrestrial days 鈥� 600 times faster than on Earth (Nature, ). Since methane is the simplest organic molecule, other more complex organic molecules would probably suffer the same fate, they argue.
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The cause of the destruction is unknown. Dust storms could play a part, or the gas could be reacting with minerals in the planet鈥檚 soil. In the latter case, Lefevre calculates that a molecule of methane could be destroyed in as little as 1 hour.