Drier than the Sahara Desert, the clouds of Venus cannot support life but Jupiter could

With three missions headed to Venus, the buzz around Earth’s mysterious twin is at an all time high. From studying surface properties to mapping its geological features, scientists aim to study how the Earth-like planet turned into a climatic hell.
Observations in 2020 had raised speculation about the presence of microbial life in the dense Venusian clouds that obscure the view of the planet’s surface. Now, a new study contradicts claims that clouds are too dry to support life. However, chances are Jupiter’s clouds will.
Published in the journal Nature Astronomy, the study indicates that the atmosphere of Venus becomes too dry for active life above the middle stratosphere. Under the direction of John E. Hallsworth of Queen’s University, Belfast, the researchers calculated the water activity in the clouds of Venus and other planets in the solar system from temperature observations and the abundance of water vapor.
“The most extreme life on Earth would have no chance of living in the clouds of Venus,” Hallsworth told Cnet.com, adding that the clouds of Venus are an order of magnitude drier than the desert of Sahara. It should be noted that the Sahara has a water activity of 0.25 while the clouds of Venus are at 0.004.
An oblique radar view of the largest block in the Venus Lowlands. (Photo: Paul Byrne, based on original NASA / JPL images)
WHY DO ASTRONOMS THINK THAT THE CLOUDS OF VENUS COULD SUSTAIN LIFE?
The theory that clouds could have microbial activity came from an observation of astronomers when they noticed the chemical signature of phosphine, a harmful gas that on Earth is only associated with life, in the clouds in 2020. Two telescopes in Hawaii and Chile have spotted the signatures in the thick Venusian clouds.
On Earth, there are only two ways to form phosphine: One is in an industrial process. (The gas was produced for use as a chemical warfare agent during World War I.) The other way is part of a kind of poorly understood function in animals and microbes. Astronomers have speculated on a scenario of how life could exist on the inhospitable planet where surface temperatures are around 800 degrees (425 degrees Celsius) without water.
The phosphine could come from some sort of microbes, probably single-celled, inside these sulfuric acid droplets, living their entire lives within 10 miles of depth, study co-author David Clements said, an astrophysicist from Imperial College London. at the time.

The northern hemisphere is shown in this overview of the surface of Venus. (Photo: Nasa)
A LONG RESEARCH OF SIX DECADES
The idea of ââsurvival of life in the clouds of Venus was first proposed by astronomer Carl Sagan and biophysicist Harold Morowitz in 1967 and was later suggested by Mark Bullock and David Grinspoon. Between the years 1962 and 1978, various probes were sent to the planet which showed that at about 40 to 43 kilometers in the atmosphere of Venus, it would be possible for the planet to harbor microbial life.
Although the idea is unique, the presence of a high content of sulfuric acid in the clouds makes it impossible to maintain microbial activity. This high sulfur content makes water activity extremely low in clouds.

A composite view of Jupiter. (Photo: Nasa)
JUPITER HAS MORE WATER ACTIVITY THAN VENUS
While Venus has extremely low water activity, Jupiter surprisingly has water activity of 0.585, more than Mars at 0.537. Researchers say this creates conditions for biological activity on the planet, which could be restricted due to other factors.
Researchers who studied data from NASA’s Galileo spacecraft, which launched a probe deep into Jupiter’s atmosphere, have found that under the huge storms swirling through the atmosphere, there are conditions that could promote life. . While other factors play a role in the sustenance of microbes, the readings are similar to those found on Earth that are suitable for microbial activity.