General Mars
  Implications of Life

  Definition of Life
  Martian Meteorite

Data Analysis
  Thin Section Analysis
  Isotope Analysis
  Gas Chromatograph Mass Spectrometer
  Infrared Spectroscopy
  Alpha-Proton X-Ray Spectrometer
  Detection of Carbon Complexes
  Labeled Release
  Gas Exchange
  Pyrolytic Release
  Stimulus Response Experiments

Scientific Research and Design
Data Analysis -- Labeled Release

 This experiment from the Viking series is based upon the assumption that extant life would metabolize carbon compounds and produce gaseous waste. So, given a sample exposed to radioactively marked carbon compounds, we are looking for released carbon 14. As their were many difficulties with possible false-positives when this was used in conjunction with the Viking experiments, many adjustments were made to the protocol to give more clear and decisive data. For further information about labeled release, click here.

Positive: Finding released carbon 14 after exposing Martian soil. Then, after raising temperature, finding carbon 14 once again. 

Negative: No released carbon 14. This result is unlikely as they did have released carbon 14 in the Viking experiments initially. Another negative would be to find released carbon 14 in the first exposure and then to find it again in the control experiment at the higher temperature allowing only chemical reactions to be the cause. 

False-Positive: As learned from the Viking experience, there are many that must be accounted for beforehand in order to get clear results. Only sample screened positively with the GCMS will be tested and then only at sites that rule out other false-positives. Clays on Mars will also be tested as a control ruling out further false-positives. Hopefully, our refined Labeled Release experiment will be much more reliable than the Viking's. 

mitCopyright © 2000 Massachusetts Institute of Technology
Comments and questions to Last updated: 10 December, 2000