The key to solving the mystery of the Viking results is the discovery of perchlorate on the Martian surface in 2008.

Did the Viking missions discover life on Mars 50 years ago? These scientists think so

Source: space
Source Link: https://www.space.com/space-exploration/search-for-life/did-the-viking-missions-discover-life-on-mars-50-years-ago-these-scientists-think-so