NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA.
Science. 2013 Jul 19;341(6143):263-6. doi: 10.1126/science.1237966.
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 ((40)Ar), 0.0193(±0.0001); nitrogen (N2), 0.0189(±0.0003); oxygen, 1.45(±0.09) × 10(-3); carbon monoxide, < 1.0 × 10(-3); and (40)Ar/(36)Ar, 1.9(±0.3) × 10(3). The (40)Ar/N2 ratio is 1.7 times greater and the (40)Ar/(36)Ar 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 (40)Ar/(36)Ar ratio is consistent with martian meteoritic values, which provides additional strong support for a martian origin of these rocks. The isotopic signature δ(13)C from CO2 of ~45 per mil is independently measured with two instruments. This heavy isotope enrichment in carbon supports the hypothesis of substantial atmospheric loss.
利用好奇号火星车上的样品分析仪器套件进行的多次大气测量获得了混合体积和同位素比值，结果如下：二氧化碳 (CO2)，0.960(±0.007)；氩-40 ((40)Ar)，0.0193(±0.0001)；氮气 (N2)，0.0189(±0.0003)；氧，1.45(±0.09) × 10(-3)；一氧化碳，< 1.0 × 10(-3)；以及 (40)Ar/(36)Ar，1.9(±0.3) × 10(3)。(40)Ar/N2 比值比 1976 年维京着陆器质谱仪报告的值高 1.7 倍，而 (40)Ar/(36)Ar 比值则低 1.6 倍，而其他值与维京号和遥感观测值基本一致。(40)Ar/(36)Ar 比值与火星陨石的值一致，这为这些岩石的火星起源提供了额外的有力支持。来自 CO2 的同位素特征 δ(13)C 约为 45‰，这是由两台仪器独立测量的。碳的这种重同位素富集支持了大气大量损失的假说。
