Something unexpected was discovered in the cloud decks of Venus, our closest planetary neighbor. While no one is saying they are aliens, some type of alien microorganism is on the list of possible explanations for why a chemical was first observed there that should not be floating above the planet.
The chemical is phosphine, or PH3, which is a compound made of phosphorus attached to three hydrogen atoms. On earth, it is believed that certain microbes that thrive in oxygen-free environments, such as a sewage treatment plant, produce the chemical. The gas is highly toxic to humans and smells like rotting fish.
It was identified in observations of Venus made through telescopes in Hawaii and Chile in 201
Interestingly, the altitude at which the phosphine was detected is one of the more hospitable areas in the solar system beyond Earth, with temperatures and pressures comparable to the surface of our planet. However, there is still the problem of sulfuric acid clouds which are certainly hostile to much of the life we know and should also destroy phosphine.
“These are conditions that don’t exactly welcome life as we know it,” says Brendan Burns, an astrobiologist at the University of New South Wales, Australia.
A team led by Jane Greaves of Cardiff University and the University of Cambridge in the UK explained the discovery in an article published in Nature Astronomy on Monday. They tried to explain the mysterious presence of PH3 in the clouds, taking into account various atmospheric, chemical and geological processes. Lightning, volcanoes, solar wind, and even meteors have been investigated as possible sources, but none match the observations.
“If no known chemical process can explain PH3 in the upper atmosphere of Venus, it must be produced by a process that has not previously been considered plausible for Venusian conditions,” the article says. “This could be unknown photochemistry or geochemistry or possibly life.”
The scientists further emphasize that the detection of PH3 is not solid evidence of life, but only of abnormal and unexplained chemistry.
To find out what exactly is happening in the clouds of Venus, new robotic probes, balloons or other spacecraft may need to be sent to explore and test them. Meanwhile, the possibilities have fueled many astronomers.
Life on Venus?
“It’s incredibly exciting,” said David Grinspoon, senior scientist at the Planetary Science Institute. “It’s a legitimate candidate biosignature (a piece of data that could indicate the presence of life) on another planet. Possibly the best we’ve found so far.”
Grinspoon is a widely recognized expert on Venus who was not involved in the new discovery, but first wrote about the possibility of a cloud biosphere on Venus in 1997 and has been pushing the idea since then. He points out that prior to this latest discovery, phosphine had been identified as the ideal biosignature on rocky planets.
“It is a molecule that should not be present in the atmosphere by ordinary chemical processes and should have a very short lifespan. If it is there, there is an active source. And then the question arises, what is that source?” And there is no obvious non-biological source. ”
Astronomer Stephen R. Kane of the University of California-Riverside, also not involved in the work, points out that some research suggests that Venus was habitable in the distant past, perhaps over a billion years ago. He suggests that any “biology in the atmosphere could be the last surviving members of an earlier Venusian biosphere”.
But Kane says there is reason to be skeptical that “life” in the clouds is the best explanation.
“As mentioned in the article, biological interpretation is suggested because we currently cannot model a geological solution. The chemistry of possible geological and biological signatures is enormous and there is an ongoing effort to fully explore this parameter space. That is, there is undoubtedly such existing geological explanations that have not yet been realized. “
There is also the problem of how anything, even tiny microbes, can make a lifestyle out of floating indefinitely in the sky, generation after generation. Staying at Goldilocks height above the extreme heat and the cold, unforgiving transition into space, as a microbe is likely to swim in droplets of liquid, seems very unlikely.
Greaves is also the co-author of a paper released last month, thewhen they have dried up at lower, hotter altitudes only to revive and continue their life cycle, when atmospheric processes lift them higher to be rehydrated in the habitable zone above Venus.
Kevin McGouldrick, a researcher at the University of Colorado Boulder who specializes in the clouds of Venus, says, “It’s further evidence that we don’t know as much about the Venusian atmosphere as we thought.”
He told me he considered the discovery “less earth-shaking,” but ultimately helpful in fueling the search for biosignatures and the unknown biology that may be behind them.
“These scientists have found solid evidence of the existence of a molecule that was not expected to be there. If the observations are not wrong, it means our expectations were wrong. And if our expectations were wrong, this represents one Opportunity for growth in knowledge. “
What about mars
We were in a very similar situation before. When NASA landed theAn experiment was carried out with which chemical reactions in the soil could be detected. The experiment known as the LR experiment turned out positive – it showed signs that the red planet contained life.
But in the years since then, planetary researchers have determined that the discovery was most likely a mistake. Mars has no existing life on its surface, but it could be in the past. So the problem was that NASA put the alien cart in front of the alien horse. We did not fully understand the geochemical processes on the surface of Mars. When we discovered a funky chemistry there was a basic wave of excitement, but we may have jumped the gun.
Although the leading scientists of the LR experiment still believe they discovered life in 1976, there is no definitive evidence – and it has been 40 years since the announcement was made.
So our search for life outside the earth continues.look for signs in the Martian soil. At the moment we seem to be able to add the clouds of Venus to the list of potentially habitable corners in the dark forest of the cosmos.
Much remains to be done to elucidate the true nature of phosphine in its upper atmosphere. Not only will biologists be intrigued, but chemists and geologists will hope to learn more about the chemical too. The only point everyone can agree on is that this new connection, which might resemble a microbial alien fart, requires a closer look.
“We have a responsibility to conduct further research and determine the true source of the phosphine,” says Kane, referring to possible missions NASA is developing to send orbiters, landers or atmospheric probes to our stormy neighbors. “Through these types of missions we can fully answer this question of possible life in the Venusian clouds.”