Methane on Mars (image) Max-Planck-Gesellschaft Caption This chart depicts the calculated methane concentrations in parts per billion (ppb) on Mars during summer in the Northern hemisphere. Violet and blue highlights are indications for little quantities of methane, red highlights for larger ones. Credit NASA Usage Restrictions None Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.