According to recent reports, space scientists using infrared spectrometers at observatories in Hawaii and Chile have detected low levels of methane in the Martian atmosphere. This finding is consistent with results from as far back as 2003 when several studies reported methane at approximately 45 ppb.  Observers performing the latest work conclude that the observed methane must be of recent origin, given the short half-life of atmospheric methane due to photodegradation. 

The connection of these findings with the possibility of past or present life on Mars has proven irresistable. I’m sure there are group leaders beavering away at mission proposals this very moment based upon these findings.

An explanation that is much less exciting and much more challenging in regard to grant proposals is the abiotic explanation. Here on earth there we have a lesser known and widely overlooked abiotic theory of hydrocarbon origin. Abiotic hydrocarbons are often referred to as primordial and are known to exist in planetary atmospheres elsewhere.

According to John S. Lewis, Physics and Chemistry of the Solar System, 2nd edition, 2004, Elsevier, Inc.,  p. 159, the mole fraction of methane in the atmosphere of Jupiter is 0.001 and for Saturn it is 0.002.  The mole fractions of water are 0.001 and 0.002 respectively. Among heavy atom species, only ammonia, hydrogen sulfide, neon, and argon approach these levels within a factor of 0.5 to 0.1.

Oxygen and carbon are two of the most highly abundant heavy atoms and to see them richly represented as their respective hydrogen compounds isn’t so surprising.

At some point in the formation of the solar system, atomic carbon and atomic hydrogen were cool enough to collide and form molecular methane.  Hydrogen with its larger mole fraction would be expected to dominate bond forming interactions with carbon atoms, forming H-saturated methane.

Given the abundance of methane in the gas giants (and don’t forget the methane atmosphere of Titan)  it is hard to discount that Mars has trapped methane in the vast interstitial spaces of the interior of the planet. Methane is known to form clathrate structures with water, so perhaps the proposed underground reservoir of Martian water is comingled with methane.

I believe we should be exploring Mars. But I am increasingly uncomfortable with this stream of “Entertainment Tonight” titillation coming from NASA in regard to the possibility of life on Mars.  Perhaps our culture isn’t as advanced as we assume. Space exploration has always had a large political prestige component to it. Contractors need new contracts and politicians are always keen to bring funding to their districts.  If it takes our lesser angels to make it work, then so be it.

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