A key tracer used to estimate how much atmosphere Mars lost can change depending on the time of day and the surface temperature on the Red Planet, according to new observations by NASA-funded scientists. Previous measurements of this tracer—isotopes of oxygen—have disagreed significantly. An accurate measurement of this tracer is important to estimate how much atmosphere Mars once had before it was lost, which reveals whether Mars could have been habitable and what the conditions might have been like.
Source:
https://phys.org/news/2019-09-insight-atmosphere-mars-lost.html