Abundance and Isotopic Composition of Gases in the Martian Atmosphere from the Curiosity Rover
Abundance and Isotopic Composition of Gases in the Martian Atmosphere from the Curiosity Rover
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DOI：
10.1126/science.1237966
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发表时间：
2013-07-19
期刊：
影响因子：
56.9
通讯作者：
Trainer, Melissa
中科院分区：
文献类型：
--
作者：
Mahaffy, Paul R.;Webster, Christopher R.;Trainer, Melissa
通过在Currency探测器上的火星仪器套件中进行的样品分析重复大气测量，获得的体积混合和同位素比率为：二氧化碳（CO2），0. 960（+/-0.007）;氩-40（Ar-40），0.0193（+/-0.0001）;氮（N-2），0.0189（+/-0.0003）;氧，1.45（+/-0.09）× 10（-3）;一氧化碳，< 1.0 × 10（-3）;和Ar-40/Ar-36，1.9（+/-0.3）× 10（3）。Ar-40/N-2的比值比1976年维京海盗着陆器质谱仪报告的值大1.7倍，Ar-40/Ar-36的比值比1976年报告的值小1.6倍，而其他值与维京海盗和遥感观测结果基本一致。Ar-40/Ar-36的比值与火星陨石值一致，这为这些岩石的火星起源提供了额外的有力支持。二氧化碳的同位素特征δ C-13类似于每密耳45，是用两台仪器独立测量的。这种碳同位素的重富集支持了大量大气损失的假设。
Volume mixing and isotope ratios secured with repeated atmospheric measurements taken with the Sample Analysis at Mars instrument suite on the Curiosity rover are: carbon dioxide (CO2), 0.960(+/-0.007); argon-40 (Ar-40), 0.0193(+/-0.0001); nitrogen (N-2), 0.0189(+/-0.0003); oxygen, 1.45(+/-0.09) x 10(-3); carbon monoxide, < 1.0 x 10(-3); and Ar-40/Ar-36, 1.9(+/-0.3) x 10(3). The Ar-40/N-2 ratio is 1.7 times greater and the Ar-40/Ar-36 ratio 1.6 times lower than values reported by the Viking Lander mass spectrometer in 1976, whereas other values are generally consistent with Viking and remote sensing observations. The Ar-40/Ar-36 ratio is consistent with martian meteoritic values, which provides additional strong support for a martian origin of these rocks. The isotopic signature delta C-13 from CO2 of similar to 45 per mil is independently measured with two instruments. This heavy isotope enrichment in carbon supports the hypothesis of substantial atmospheric loss.