Complexity Analysis of the Viking Labeled Release Experiments

Abstract

The only extraterrestrial life detection experiments ever conducted were the three which were components of the 1976 Viking Mission to Mars. Of these, only the Labeled Release experiment obtained a clearly positive response. In this experiment 14 C radiolabeled nutrient was added to the Mars soil samples. Active soils exhibited rapid, substantial gas release. The gas was probably CO 2 and, possibly, other radiocarbon-containing gases. We have applied complexity analysis to the Viking LR data. Measures of mathematical complexity permit deep analysis of data structure along continua including signal vs. noise, entropy vs.negentropy, periodicity vs. aperiodicity, order vs. disorder etc. We have employed seven complexity variables, all derived from LR data, to show that Viking LR active responses can be distinguished from controls via cluster analysis and other multivariate techniques. Furthermore, Martian LR active response data cluster with known biological time series while the control data cluster with purely physical measures. We conclude that the complexity pattern seen in active experiments strongly suggests biology while the different pattern in the control responses is more likely to be non-biological. Control responses that exhibit relatively low initial order rapidly devolve into near-random noise, while the active experiments exhibit higher initial order which decays only slowly. This suggests a robust biological response. These analyses support the interpretation that the Viking LR experiment did detect extant microbial life on Mars.

A Presumptive Fossilized Bacterial Biofilm Occurring in a Commercially Sourced Mars Meteorite

“…This conclusion appears consistent with recent findings from the NASA Mars Curiosity Rover of fine-grained sedimentary rocks which were interpreted to represent an ancient lake preserving evidence of an environment that would have been suited to support life [9]. It is also relevant to note that a recent re-evaluation of the results from the Labelled Release Experiment on the Mars-Viking probe of 1976 has concluded that extant Martian surface microbiology was most likely to have been discovered at this time [10].…”

Mars Astrobiology: Recent Status and Progress

“…This suggests a robust biological response. These analyses support the interpretation that the Viking LR experiment did detect extant microbial life on Mars (Bianciardi et al 2012).…”

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“…In 1986 and again in 2012 a careful re-examination of all the 1976 data led to the startling (but little publicised) conclusion that the Viking results may have indicated a positive result for primitive life in sub-surface niches on Mars [2]. What is true beyond doubt is that the results of the 1976 Viking experiments remain at the very least fully consistent with the presence of microbial life on Mars.…”