Primordial argon isotope fractionation in the atmosphere of Mars measured by the SAM instrument on Curiosity and implications for atmospheric loss.
Geophys Res Lett
; 40(21): 5605-5609, 2013 Nov 16.
Article
em En
| MEDLINE
| ID: mdl-25821261
ABSTRACT
[1] The quadrupole mass spectrometer of the Sample Analysis at Mars (SAM) instrument on Curiosity rover has made the first high-precision measurement of the nonradiogenic argon isotope ratio in the atmosphere of Mars. The resulting value of 36Ar/38Ar = 4.2 ± 0.1 is highly significant for it provides excellent evidence that "Mars" meteorites are indeed of Martian origin, and it points to a significant loss of argon of at least 50% and perhaps as high as 85-95% from the atmosphere of Mars in the past 4 billion years. Taken together with the isotopic fractionations in N, C, H, and O measured by SAM, these results imply a substantial loss of atmosphere from Mars in the posthydrodynamic escape phase.
Texto completo:
1
Bases de dados:
MEDLINE
Idioma:
En
Revista:
Geophys Res Lett
Ano de publicação:
2013
Tipo de documento:
Article
País de afiliação:
Estados Unidos