Observed variations of methane on Mars unexplained by known atmospheric chemistry and physics

@article{Lefvre2009ObservedVO,
  title={Observed variations of methane on Mars unexplained by known atmospheric chemistry and physics},
  author={Franck Lef{\'e}vre and François Forget},
  journal={Nature},
  year={2009},
  volume={460},
  pages={720-723}
}
The detection of methane on Mars has revived the possibility of past or extant life on this planet, despite the fact that an abiogenic origin is thought to be equally plausible. An intriguing aspect of the recent observations of methane on Mars is that methane concentrations appear to be locally enhanced and change with the seasons. However, methane has a photochemical lifetime of several centuries, and is therefore expected to have a spatially uniform distribution on the planet. Here we use a… 

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