Argon Isotopes Provide Robust Signature of Atmospheric Loss

This image, made by the quadrupole mass spectrometer in the SAM suite of instruments in NASA Curiosity Mars rover. shows the ratio of the argon isotope argon-36 to the heavier argon isotope argon-38, in various measurements.

This image, made by the quadrupole mass spectrometer in the SAM suite of instruments in NASA Curiosity Mars rover. shows the ratio of the argon isotope argon-36 to the heavier argon isotope argon-38, in various measurements.