Tunable laser spectrometer instruments using the MDL semiconductor lasers are capable of measuring emission rates of carbon dioxide and methane on Earth and other planets.
JPL and NASA have a long history of flying tunable diode laser spectrometers on Earth and planetary missions for atmospheric and trace gas analysis. MDL has been involved in the design and fabrication of space-qualified semiconductor lasers since its inception. Stable isotope ratios of H, C, and O are powerful indicators of a wide variety of planetary geophysical processes, and for Mars they reveal the record of loss of its atmosphere and subsequent interactions with its surface such as carbonate formation. The in situ measurements of the isotopic ratios of D/H and 18O/16O in water and 13C/12C, 18O/16O, 17O/16O, and 13C18O/12C16O in carbon dioxide in the martian atmosphere were made from the Curiosity rover using the Sample Analysis at Mars (SAM) tunable laser spectrometer (TLS).