No detection of methane on Mars from early ExoMars Trace Gas Orbiter observations

  title={No detection of methane on Mars from early ExoMars Trace Gas Orbiter observations},
  author={Oleg I. Korablev and Ann Carine Vandaele and Franck Montmessin and Anna A. Fedorova and Alexander Trokhimovskiy and François Forget and Franck Lef{\'e}vre and Frank Daerden and Ian R. Thomas and Lo{\"i}c Trompet and Justin T. Erwin and Shohei Aoki and S{\'e}verine Robert and Lori Neary and S{\'e}bastien Viscardy and Alexey V. Grigoriev and Nikolay I. Ignatiev and Alexey V. Shakun and Andrey Patrakeev and Denis A. Belyaev and J L Bertaux and Kevin S. Olsen and Lucio Baggio and Juan Alday and Yu. S. Ivanov and Bojan Ristic and John Mason and Yannick Willame and C{\'e}dric Depiesse and Laszlo Hetey and Sophie Berkenbosch and Roland Clairquin and Claudio Queirolo and Bram Beeckman and Eddy Neefs and Manish R. Patel and Giancarlo Bellucci and J{\'o}se Juan Lopez‐Moreno and Colin F Wilson and Giuseppe Etiope and Lev M. Zelenyi and H{\aa}kan Svedhem and Jorge L. Vago},
The detection of methane on Mars has been interpreted as indicating that geochemical or biotic activities could persist on Mars today1. A number of different measurements of methane show evidence of transient, locally elevated methane concentrations and seasonal variations in background methane concentrations2–5. These measurements, however, are difficult to reconcile with our current understanding of the chemistry and physics of the Martian atmosphere6,7, which—given methane’s lifetime of… 
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