Background levels of methane in Mars’ atmosphere show strong seasonal variations

@article{Webster2018BackgroundLO,
  title={Background levels of methane in Mars’ atmosphere show strong seasonal variations},
  author={Christopher R. Webster and Paul R. Mahaffy and Sushil K. Atreya and John E. Moores and Gregory J. Flesch and Charles Malespin and Christopher P. McKay and German M. Martinez and Christina L. Smith and Javier Mart{\'i}n‐Torres and Javier G{\'o}mez-Elvira and Mar{\'i}a P. Zorzano and Michael H. Wong and Melissa G. Trainer and Andrew Steele and Douglas Archer and Brad Sutter and Patrice Coll and Caroline Freissinet and Pierre‐Yves Meslin and Raina V. Gough and Christopher H. House and Alexander A. Pavlov and Jennifer L. Eigenbrode and Daniel P. Glavin and John C. Pearson and Didier Keymeulen and Lance E. Christensen and Susanne P. Schwenzer and Rafael Navarro‐Gonz{\'a}lez and Jorge Pla‐Garc{\'i}a and Scot C. R. Rafkin and {\'A}lvaro Vicente-Retortillo and Henrik Kahanp{\"a}{\"a} and Daniel Vi{\'u}dez‐Moreiras and Michael D. Smith and Ari-Matti Harri and Maria Genzer and Donald M. Hassler and Mark T. Lemmon and Joy Crisp and Stanley P. Sander and Richard W. Zurek and Ashwin R. Vasavada},
  journal={Science},
  year={2018},
  volume={360},
  pages={1093 - 1096}
}
Measuring martian organics and methane The Curiosity rover has been sampling on Mars for the past 5 years (see the Perspective by ten Kate). Eigenbrode et al. used two instruments in the SAM (Sample Analysis at Mars) suite to catch traces of complex organics preserved in 3-billion-year-old sediments. Heating the sediments released an array of organics and volatiles reminiscent of organic-rich sedimentary rock found on Earth. Most methane on Earth is produced by biological sources, but numerous… 

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