Who’s Out There—On Venus?

After landing on the surface of Venus in December 1970, the Soviet’s Venera 7 lasted only 23 minutes in the 470ºC heat under atmospheric pressure 90 times Earth’s.
The winds on the surface blow gently along the channels and many small basins, over the three large upland areas and across the extensive lava fields, but there is little hope for finding life there now. The hot reservoirs beneath the surface and the liquid magma are too extreme, even to host silicone life.
Russian Lander Venera 7

Russian Lander Venera 7

If life ever found water and energy to survive in Venus’ first hundreds of million years, it would have evolved very rapidly and disappeared even more rapidly as the huge green house accumulated carbon dioxide and grew very hot, presaging Earth’s distant future.

In those first years, however, there could have evolved organosilicon critters in heat-tolerant solvents, provided they invented an oxidative metabolism. As the planet’s heat became intolerable, some minute critters could have escaped into the dense carbon dioxide/sulfuric acid atmosphere, which is also rich with hydrogen, helium, nitrogen, ammonia and methane. The temperature at 50 kilometers up is still welcoming, cool enough for stable organics.
The atmosphere of Venus is pure carbon dioxide up to thirty kilometers above the surface. Its temperature ranges from 80 to 33°C and its atmospheric pressure is 1.1 to .3 times sea level pressure on Earth. The middle cloud layer ranges from 30 to 4°C, possibly keeping organic macromolecules intact.
Water is scarce in the atmosphere and is frozen into ice above 58 km, where water is dissociated by UV light and cosmic radiation. Hygroscopic sulfuric acid forms a haze from 30 to 48 km, then forms clouds of droplets. Though organics are sparse in the atmosphere, the good news is that extreme acidophilic microorganisms have been found on Earth, so why not here?
The bad news is that none of the many probes of Venus’ atmosphere have detected organic chemicals, so if they exist, they are not abundant.
It’s still fun to speculate what might live up there in Venus’ sulfuric acid/carbon dioxide clouds. There is plenty of energy from strong polar winds and sunlight. Lightning could have helped produce organics, and Pioneer Venus 2 detected ethane.
The bottom line—energy producing reactions are possible, like SO2 + H2 + 2CO → 2CO2 + H2S + energy, with sunlight powering the reverse reaction CO2 + sunlight + 2H2S → CHOH +H2O +S2.
Indeed, hydrogen sulfide is more concentrated just below the lowest clouds, a hopeful sign. Also, hopeful is the fact that the clouds of Venus are long lasting, so could provide droplet habitats for many microbe generations. Micron-sized microbes coated with sulfur compounds are another possibility.
Though the early transition of life from surface water on Venus to two different thermal layers of sulfuric acid clouds is a possibility, it becomes remote when considering the scarcity of water and organic reactants and the high acidity of the ethereal environment above Venus. We might do better, looking for life in the gas giant planets.
For more details see Cosmic Biology by Irwin and Schulze-Makuch
Enhanced by Zemanta
Recommended for you  Fan’s Choice – Top Ten Science Fiction Films of All Time (Part 1)

Cary Neeper is an avid student of complexity theory, sustainability, steady-state economics, and the impact of cosmology on issues of science and religion. She grew up in the foothills of Hayward, California, where she helped rack dried fruit on her father’s 40-acre apricot ranch. After studying zoology/chemistry and religion at Pomona College and medical microbiology at the University of Wisconsin, she moved with her husband to northern New Mexico, where they raised their family. The Neepers still live in the Southwest with a friendly menagerie of dogs, fish, chickens, geese, ducks and a turkey called Little Bear. Cary plays string bass with local folk, symphony and jazz groups and tennis with local retired physicists. She paints landscapes in acrylics, including the cover art for her first Penscript title, The Webs of Varok. Cary's first novel and Webs of Varok prequel A Place Beyond Man was originally published in 1975 by Charles Scribner’s Sons, Dell, and Millington, London. Cary re-released A Place Beyond Man as an Author’s Guild Backinprint edition, now available from online booksellers. Its themes of sustainability and interspecies cooperation have now grown into new adventures for its human, elll and varok family as they travel the alternate 21st century Solar System in the five-volume Archives of Varok, coming from Penscript Publishing House in 2012–2014. Cary’s other works include two musical science fiction comedies “U.F.F.D.A.!” and “Petra and the Jay,” as well as newspaper and magazine articles, essays, short stories, and book reviews for The Christian Science Monitor.

You may also like...

Subscribe To Our Newsletter

Join our mailing list to receive the latest news and updates from Astronaut.com.

You have Successfully Subscribed!