If you were to consider other places in the solar system where extraterrestrial life might be found, your thoughts first might wander to gas giant moons such as Enceladus or Europa. Perhaps Titan, even.
Planet-wise, Mars is the clear leader, despite it being relatively barren.
Well ... welcome to the 2020s, where nothing is quite as expected.
Earlier this week, scientists revealed the discovery of phosphine gas in the atmosphere of Venus. What is phosphine, and what does it have to do with extraterrestrial activity?
Phosphine is an extremely toxic gas that is thought to be produced by microbes on Earth. Scientists consider it a biosignature, meaning that it is a compound that could be produced by living matter. Scientists and astronomers are still trying to grasp the inner workings of Venus’ atmosphere, so while there is a chance it could be produced in the atmosphere naturally, there is currently no known process where that could occur, based on what we know about it.
But, who knows what processes go on in the ultra-acidic, ultra-dry atmosphere of the nearest planet to Earth? Something unusual, perhaps.
Now, if you want to get excited about extraterrestrial life on Venus, it’s not quite the time. Not quite.
There could very well end up being a reasonable chemical explanation for the phosphine gas. The extraterrestrial explanation, however, is quite tantalizing. A newly discovered chemical process that produces phosphine gas might be exciting for your neighborhood NASA scientist, but it would easily be met with a “meh” by the general public.
There hasn’t been meaningful exploration of Venus in nearly a decade — the last was the European Space Agency’s Venus Express that lasted until the early-2010s.
It begs the question: How much do we really know about our nearest neighbor?
Sure, we know about its hellish heat, its unbearable atmospheric pressure, its poisonous atmosphere and its geology. But what other secrets does Venus hold from us? Perhaps life, in a form we Earthlings are unaware of, has been thriving in the Venusian clouds for quite a long time.
Or, perhaps it’s just a dead, barren, hellish rock.
To find out for sure, it’s time to again prioritize Venus as a place of study. If we send missions, and there is life there, we will discover it. We need to take advantage of this discovery and Venus’ position relative to Earth, but we must also do it carefully and responsibly. In the still unlikely scenario that there is life on Venus, we must observe and do our best to not interfere.
You can read about the phosphine discovery in the journal Nature Astronomy: https://www.nature.com/arti cles/s41550-020-1174-4.