What Would Life on Venus Look Like?

Venus, Via Wikimedia Commons.

Note: the phosphine ‘discovery’ on Venus has since been disproven; scientists confirmed in 2021 that the phosphine that was reported to be prevalent in Venus’s atmosphere was probably sulfur dioxide, not phosphine. This effectively closes the article to the changes of time, but nevertheless serves as a testament to the unending pursuit of knowledge, which continues to lead us past the blind hypotheses and to the solid facts. It is a lesson that no science, whether rock solid or unproven, should be taken to be an insoluble fact (it does not mean, however, that we should push science aside or disregard it).

In the previous part of this two-part entry, we discussed the apparent discovery of phosphine in the upper atmosphere of Venus. 

Let us now assume that both the discoveries of phosphine and glycine are confirmed. Assuming that the confirmation and later research concludes that life does certainly exist on Venus: what might Venusian life look like?

Characteristics of Venusian Life

Life on other planets has always been a forefront topic in theoretical science, and most of all, science fiction. We often consider these extraterrestrials “little green men,” who have humanlike appendages, body structures, and facial features. The only notable differences are their nose and eye shapes, their lean appendages, and the color of their skin. 

This Hollywood assumption is, at the very best, pseudoscientific in the way that it considers extraterrestrials to be physically and genetically similar to humans. We must remember how evolution works before we make our earth-biased assumptions. Evolution by natural selection is the “survival of the fittest, as in the most adaptable to the natural environment or ecological change.” An organism with the genes which suit best the environment in which they live, will be most likely to survive and reproduce. In the case of an environment suitable for life on a planet completely different from earth, then life on that planet will likely have very different features than on our planet.

Let us first begin with the more likely of the already unlikely two: microbes – microbial life is arguably the only life form that could exist on Venus. 

These microbes will be much different from those on earth; although conditions in the upper-atmosphere of Venus are remarkably similar to Earth’s, the composition of the region is much different – Venus’s atmosphere is composed mainly of carbon dioxide, so creatures that consume oxygen, like humans, will not and cannot exist there.

If microbial life exists on Venus, the microbes likely will have distinct features that allow them to survive in its atmosphere. Their method of obtaining energy will be quite different from Earthly organisms, but we can reasonably assume that carbon dioxide or another substance with relative abundance in Venus’s atmosphere would act as a reactant. 

The 186 mph (85 m/s) winds in Venus’s upper atmosphere would allow any microbial life to remain aloft and, likely, within that “goldilocks” region of Venus’s atmosphere. They could, therefore, survive in Venus’s temperate upper atmosphere for extended periods of time – from their birth to their death, even.

Though much more unlikely, there also stands the infinitely small possibility that larger life, perhaps similarly sized to human life, could exist there. It is, however, extremely improbable that any multicellular (if cells even constitute organisms on Venus), let alone intelligent, life on Venus. Nevertheless, out of pure curiosity, let us examine what potential macroextraterrestrial life may look like in the upper atmosphere of our planetary neighbor.

Large extraterrestrial life on Venus must be suitable for the environment in which it resides. In terms of an upper atmosphere, it is likely that these larger organisms will need to be somewhat floating, as the wind may not be strong enough to keep their bodies suspended in such a high altitude. 

As with on Earth, the best method to counter gravity without opposite thrust is by maximizing air resistance. This assumption is based on my own speculation, as many tend to point to hydrogen-balloon-like structures in these organisms that would allow them to simply float around. When I consider large life on Venus, I think of an umbrella-like creature that works similar to a parachute. I do not consider a hydrogen balloon – whose lower density would allow it to float upwards to a point at which its pressure is similar to that of the surrounding atmosphere – necessary, because umbrella-like features would, theoretically, be sufficient enough, assuming strong winds, to keep the organism aloft at a similar altitude. Between the air resistance the umbrella accentuates and the ultra-fast wind speeds in the upper atmosphere, the organisms could remain aloft without the need for a larger balloon that is made up of hydrogen, which is relatively scarce (at least compared to carbon dioxide) in Venus’s atmosphere.

Regarding energy consumption, the larger organisms could feed off the microbial life in the same way whales feed off plankton: as they flow through Venus’s atmosphere, they essentially breathe in the microbial life and consume them. They could also feed off matter, like carbon dioxide. 

Wrapping it up

Nevertheless, virtually anything is possible regarding the characteristics of Venusian life. The potential discoveries (discovered not to be discoveries – read the beginning of the entry) of glycine and phosphine may indicate biological processes occurring on Venus – the most improbable planet for life. For this moment, we must remain scientifically skeptical, rather than unrealistically optimistic. Regardless, let us allow the scientific process to continue in its course, and if we discover a reality in which there is no other explanation for these molecules, then perhaps we can begin to consider life a legitimate possibility on Venus. For now, however, we must seek to understand other natural processes that may cause such an abundance of these biomolecules. 

Thank you all, again, for reading through this entry. Take care and, as always, stay curious.

If you have any questions, comments, or corrections, please comment on this post or email learningbywilliam@gmail.com with your concerns. Thank you.

References

Life on Venus. (2022, July 04). Retrieved from https://en.wikipedia.org/wiki/Life_on_Venus

Morowitz, H., & Sagan, C. (n.d.). Life in the Clouds of Venus? Retrieved from https://www.nature.com/articles/2151259a0