Okay, Mars' molten core has pretty much cooled down, so Mars does not have much of a magnetic field, so Mars has little protection from radiation -

MARIE broke down - we know that solar radiation varied while the two spectrometers were running, but there's no way to adjust the readings over time to reflect this variability - co-variance with radiation could have shown a lot -

When water H2O is hit by radiation, you get hydrogen, oxygen, peroxides - the hydrogen, begin light, should have outgassed over the billions of years of ever lessening protection as the core cooled -

O2 hits, you get ozone - on Earth, since this is lighter, it stays at altitude

CO2, you get? - hydrocarbons? Spires hydrocarbon seeps were thought to be comet delivered, but?

Surface hits? - who knows - but simpler elements seem possible, as well as radioactive isotopes - certainly C14 - but the resulting surface radiation environment is unknown - again, this could have thrown off the spectrometers -

The floor is open for intelligent and polite discussion...

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