Can't find it now. Curiosity has an instrument to measure isotopes, which tells how its air chemistry changed over the aeons. It showed disparity in heavy vs li

Can't find it now. Curiosity has an instrument to measure isotopes, which tells how its air chemistry changed over the aeons. It showed disparity in heavy vs light gasses trapped in rocks of different ages. Light gasses are lost first, so that gave a clock on atmosphere loss. And a profile of that loss over time. Here's a sunday-supplement summary I did find: https://science.time.com/2013/07/23/revealed-how-mars-lost-its-atmosphere/ https://science.time.com/2013/07/23/revealed-how-mars-lost-i...