Hints of Life in the Clouds of Venus?

Have you seen photos of Venus?  When the planet is observed in visible light it looks like a big bland ecru ball (see above).  Put a whiteboard and some plastic rolling chairs on that puppy and you would have a corporate conference room in some awful suburban office-park.  Yet ultraviolet imaging of Venus paints a somewhat more interesting picture of swirling bands or darkness in the heady acid atmosphere of our sister planet.  But what does that mean?

The dark bands turn out to be the result of sulfur compounds (carbonyl sulfide, hydrogen sulfide and sulfur dioxide) and other yet unknown chemical compounds in the upper atmosphere of Venus.  On Earth these sulfur compounds are hallmarks of life…or of volcanic activity.  Some scientists are provocatively asking whether extremophile bacteria could have a place in the temperate upper atmosphere of Earth’ closest planetary neighbor.  The bacteria could use the rich sulfur and carbon clouds as building blocks and the UV (and other EM radiation!) bombardment of the sun for energy.  Perhaps, they muse, these dark bands are something akin to algal blooms in Earth’s oceans.

More than a billion years ago, Venus enjoyed a period of prolonged earthlike climate with surface water and an atmosphere which was not so hellishly heavy and hot.  But something went hideously awry and runaway greenhouse effect created a terrible feedback loop which changed the planet’s surface into the monstrous place it is today.  Apparently the igneous/volcanic processes of Venus are rather different than those of Earth, so it was probably not all treeferns, friendly dinosaurs, and bikini-clad aliens even before the runaway greenhouse phase melted away the old surface of Venus, but perhaps bacteria (or analogous lifeforms) could have evolved and escaped the catastrophe by moving into the upper clouds (which, as previously noted here, have temperatures not unlike those of Earth’s surface).

My guess is that Venus is lifeless as a jackhammer (though, like a jackhammer it can give the alarming appearance of life), yet even if this is the case, we should know more about all of this! What happened to Venus’ original surface? Was there ever life there?  What is going on with its volcanoes and internal geology?  What is the composition of the clouds of Venus? Is there anything there other than strange sufur compounds and esoteric hydrocarbons formed from the mixture of sulfur, carbon dioxide, and UV radiation?   Once again, our nearest neighbor is beckoning.  We need to move forward with sophisticated atmospheric probes (like VAMP) and NASA should collaborate with Russia on their next Venus mission (it looks like our governments are closer than ever anyway).  For some reason, popular imagination disdains Venus, yet the questions there seem salient, and the possibilities for a nearby Earth-sized world of unlimited energy and resources seem, well, unlimited.

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