Tags Dr. Gil Levin Viking Mission to Mars Viking Labeled Release Life Detection Experiment Mars return sample to Earth cross contamination planetary protection NASA searching for life in the solar system Enceladus Titan Europa scientific method chiro labeled release experiment Russian Mars life detection experiment Mars 2020 ESA ExoMars 2020 Martian organics in the soil SpaceX Mars plans DNA robotic instruments Mars mission sterilization Guest Dr. Gilbert Levin Tagline Dr. Gil Levin returns, Mars life updates, Viking, and more View the discussion thread.