Since then, methane has been discovered in Mars' atmosphere at 10ppb, thus reopening this debate, although in 2013 the Curiosity rover failed to detect methane at its location in levels exceeding 1.3 ppb.
Methane has been discovered in Mars' atmosphere at 10ppb, thus reopening this debate. This was since then. The Curiosity rover failed to detect methane at its location in levels. This was in 2013. These levels were exceeding 1.3 ppb.