Publisher Correction: No detection of methane on Mars from early ExoMars Trace Gas Orbiter observations.
Publisher Correction: No detection of methane on Mars from early ExoMars Trace Gas Orbiter observations.
复制标题
出版商更正：早期的 ExoMars 痕量气体轨道器观测中没有检测到火星上的甲烷。
DOI：
10.1038/s41586-019-1164-9
复制
发表时间：
2019
期刊：
影响因子：
64.8
通讯作者：
Korablev O
中科院分区：
文献类型：
--
作者：
Korablev O
在火星上探测到甲烷被解释为表明地球化学或生物活动可能在今天的火星上持续存在。许多不同的甲烷测量结果表明，甲烷浓度的瞬时，局部升高和背景甲烷浓度的季节性变化的证据。然而，这些测量结果很难与我们目前对火星大气的化学和物理学的理解相一致，考虑到甲烷的寿命长达几个世纪，这些测量结果预测甲烷的分布均匀，混合良好。在这里，我们报告了2018年4月至8月使用ESA-Roscoplant ExoMars痕量气体轨道器上的ACS和NOMAD仪器对火星大气进行的高灵敏度测量，试图探测甲烷。我们在两个半球的一系列纬度上都没有检测到任何甲烷，获得的甲烷上限约为十亿分之0.05，比以前报告的阳性检测低10到100倍。我们认为，目前的研究结果和在盖尔陨石坑中发现的背景甲烷浓度之间的和解将需要一个未知的过程，可以在甲烷扩散到全球之前迅速从低层大气中去除或隔离甲烷。
The detection of methane on Mars has been interpreted as indicating that geochemical or biotic activities could persist on Mars today. A number of different measurements of methane show evidence of transient, locally elevated methane concentrations and seasonal variations in background methane concentrations, , –. These measurements, however, are difficult to reconcile with our current understanding of the chemistry and physics of the Martian atmosphere,, which—given methane’s lifetime of several centuries—predicts an even, well mixed distribution of methane,,. Here we report highly sensitive measurements of the atmosphere of Mars in an attempt to detect methane, using the ACS and NOMAD instruments onboard the ESA-Roscosmos ExoMars Trace Gas Orbiter from April to August 2018. We did not detect any methane over a range of latitudes in both hemispheres, obtaining an upper limit for methane of about 0.05 parts per billion by volume, which is 10 to 100 times lower than previously reported positive detections,. We suggest that reconciliation between the present findings and the background methane concentrations found in the Gale crater would require an unknown process that can rapidly remove or sequester methane from the lower atmosphere before it spreads globally.