An announcement made on Monday by an international team of astronomers about the discovery of phosphine gas in the atmosphere of Venus sparked worldwide excitement about the possibility of the presence of life forms on the neighboring planet.
- In addition to being produced in industrial processes, phosphine, a colorless but smelly gas, is known to be produced only by certain species of bacteria that survive in the absence of oxygen.
- In an article published in Nature Astronomy, a team of scientists reported traces of phosphine at a concentration of around 20 parts per billion, thousands to millions of times more than one might otherwise expect.
So, is there life on Venus?
No one is saying it yet. What scientists have discovered is the presence of a chemical that is known to be produced only by a biological process and not by a natural chemical process. There are other ways to produce this chemical, for example in the bellies of volcanoes or in meteorite activity, but it would have been shown at much lower concentrations.
- In any case, scientists have ruled out all of these kinds of known possibilities that could be attributed to the presence of this gas.
- In fact, this discovery was made in 2017, and scientists verified and rechecked their data from the past three years before deciding to make it public.
- The summary of their paper in Nature Astronomy says that this presence of phosphine is “inexplicable” after careful study of all other possible sources and “production pathways in the atmosphere, clouds, surface and subsoil of Venus, or by the discharge of lightning, volcanic or meteorite “.
- So the only possible explanation for the origin of this phosphine, according to our current knowledge, could be in biological processes, the way it is produced on Earth, by certain microbes.
- In an announcement on Monday, scientists were careful to stress, on several occasions, that this was not a confirmation of the presence of life on Venus.
So why is this important?
This is the most credible evidence to date of the possibility of life outside of Earth. Scientists say it's more significant, for example, than the discovery of water on the Moon or Mars.
“In the search for extraterrestrial life, this is the biggest find, hands down. Of course, that cannot mean that there is indeed life on Venus, or elsewhere, but if you are a scientist looking for life forms on other planets, I think this is your first. real breakthrough, ”said Dibyendu Nandi of IISER. , Calcutta.
- This is how Professor Sara Seager of the Physics Department at the Massachusetts Institute of Technology, who is one of the study's authors, also described the discovery. He said the detection of the phosphine had raised Venus “higher on the scale of interesting targets” where the possible presence of life forms can be explored.
But Venus can't stand life, right?
There are several things we know about Venus that make life, as we know it, unsustainable on this planet. Venus's temperature is too high and its atmosphere is very acidic, just two of the things that would make life miserable.
- But Somak Raychaudhuri, director of the Pune-based Interuniversity Center for Astronomy and Astrophysics, suggested this phosphine could be a holdover from a time when Venus was a much more hospitable place.
- Look, this discovery opens up many interesting possibilities. We don't know how long the phosphine molecules survive.
- Additionally, we know that Venus was not always as inhospitable as it seems today.
- So one of the possibilities, if we wanted to explore the question of the presence of life on Venus, it could be whether this phosphine is in fact something left over from a time when the planet was home to life forms. These are open questions at the moment.
- All of these will be explored. What we have now is just one foot in the door. Now we can probe with more enthusiasm, ”he said.
- Infact, it's bigger than raincoats that way. Water only has a detailed relationship with life. It is not produced by life. Phosphine is produced through biological processes. So it's definitely significant and nothing like that has been discovered so far.
What could this mean for the Venus missions?
- The discovery may spark greater interest in space missions to Venus. Missions to Venus are not new.
- Spaceships have been closing in on the planet since the 1960s, and some of them have even landed.
- In fact, the Indian Space Research Organization (ISRO) is also planning a mission to Venus, tentatively named Shukrayaan, in the near future. For now, the plan is still on the drawing board.
- All future missions to Venus would now be geared towards finding new evidence for the presence of life.