After years and years of debate and uncertainty on whether we are alone in this universe or not, we came to a point in our history when scientific progress and technological breakthroughs can shed some light on this topic.
A new study conducted by a team of international researchers from UK, US and Japan, suggests that signs of life have been spotted on Venus. These signs come in the form of phosphine (PH3) gas particles. Phosphine is a flammable gas with a pungent smell, which on Earth is produced by microbes that live in oxygen-free environments. For years, astronomers have wondered if the atmosphere of Venus could offer the proper conditions for life. The discovery of phosphine made with the help of Atacama Large Millimeter/submillimeter Array (ALMA) telescope is the first step towards that claim.
Mistake or luck?
Co-author Clara Sousa-Silva, a postdoctoral researcher at the Massachusetts Institute of Technology was the first of the team who reported the presence of phosphine on Venus. “I immediately freaked out, of course. I presumed it was a mistake, but I very much wanted it to not be a mistake,” she says, according to National Geographic.
Scientists state that phosphine should not be present in the atmosphere of a lifeless planet. It is not easily made and the chemical composition of Venus’ clouds should destroy it before it gets the chance to accumulate in observable amounts. However, more studies are to be conducted because the presence of phosphine has to be verified. Phosphine fingerprint could be a false signal introduced by telescopes or by the processing of data.
David Grinspoon of the Planetary science Institute said: “It’s tremendously exciting, and we have a sort of obligatory response of first questioning whether the result is real. When somebody comes up with an extraordinary observation that hasn’t been made before, you wonder if they could have done something wrong.”
According to Science Daily, the estimated concentration value of the gas is about twenty molecules in every bilion. Small amounts of concentration could come from natural, non-biological sources such as sunlight, minerals, volcanoes or lightning, but they do not come nowhere near to the reported data, their values being at most one ten thousandth of the reported amount.
“To our great relief, the conditions were good at ALMA for follow-up observations while Venus was at a suitable angle to Earth. Processing the data was tricky, though, as ALMA isn’t usually looking for very subtle effects in very bright objects like Venus,” says Anita Richards, team member from UK. “In the end, we found that both observatories had seen the same thing faint absorption at the right wavelength to be phosphine gas, where the molecules are backlit by the warmer clouds below”
Was there ever life on Venus?
Nowadays, Venus is a scorched planet, but observations suggest that in the early history of the universe, for up to two billion years, it once had liquid water oceans and habitable surface temperatures. Therefore, Venus might have once been as friendly and habitable as Earth is today. Its transformation to the current form is attributed to the accumulation of greenhouse gases.
Penelope Boston, a NASA astrobiologist explains that “any life there now is much more likely to be a relic of a more dominating early biosphere”. Furthermore, she stated: “I think it’s a blasted hellhole now, so how much of that ancient signal could have held up?”
Could life be present on Venus after all?
In the scientific community, the opinions are split. ALMA observatory scientist John Carpenter has his doubts on this discovery. He states that the signal is faint, and the team should have performed more extensive research. Furthermore, he says that the processing of the data might have returned an artificial signal at the same frequency as the phosphine.
“They took the right steps to verify the signal, but I’m still not convinced that this is real. If it’s real, it’s a very cool result, but it needs follow-up to make it really convincing,” Carpenter says.
Photo – Pixabay