A treasure trove of clues from Curiosity reveals that ancient Mars once trapped massive amounts of CO2 in its crust, thanks to surprising concentrations of iron carbonate deep in Gale Crater. By drilling into layers laid down in a vanished lake, scientists found up to 10% siderite in sulfate-rich rocks – carbonates that orbital surveys [...]from SciTechDaily https://ift.tt/NPCTuF8
