A previous study pointed out in 2020 that Venus possessed large numbers of phosphine.
a marker that could signify the presence of extraterrestrial life. However, new studies contradict this theory.
A study with the now-retired NASA / DLR SOFIA airborne observatory has found no phosphine on Venus , a gas associated with life on Earth, which a previous study detected in 2020.
Phosphine is a gas found in Earth ‘s atmosphere, but the announcement of the discovery of phosphine above the clouds of Venus made headlines in 2020 . The reason was its potential as a biomarker. In other words, phosphine could be an indicator of life.
no trace of phosphine
Although common in the atmospheres of gas planets like Jupiter and Saturn, phosphine on Earth is associated with biology. Here, it is made up of decaying organic matter in swamps, bogs, and marshes.
” Phosphine is a relatively simple chemical compound, it’s just a phosphorus atom with three hydrogens, so you’d think it would be fairly easy to produce. But on Venus , it’s not obvious how it could be done ,” Martin Cordiner said in a statement. researcher in astrochemistry and planetary science at NASA Goddard Space Flight Center .
There may be other potential ways to form phosphine on a rocky planet, such as through lightning strikes or volcanic activity, but none of these apply if there is simply no phosphine on Venus . And according to SOFIA , there isn’t.
After the 2020 study, several different telescopes made follow-up observations to confirm or refute the finding. Cordiner and her team did the same, using SOFIA in their search.
his last effort
The recently retired SOFIA was a telescope on an airplane, and over the course of three flights in November 2021, it searched the sky of Venus for signs of phosphine . Thanks to its operation from Earth’s sky, SOFIA could make observations that cannot be accessed from ground-based observatories.
Its high spectral resolution also allowed it to be sensitive to phosphine at high altitudes in the Venusian atmosphere , between 75 and 110 kilometers above the ground, the same region as the original find, with spatial coverage over the entire Venusian disk .
The researchers did not see any signs of phosphine . According to their results, if there is any phosphine present in the Venusian atmosphere , it is a maximum of about 0.8 parts of phosphine per billion parts of everything else, much smaller than the initial estimate.
Pointing SOFIA ‘s telescope at Venus was a challenge in itself. The window during which Venus could be observed was short, about half an hour after sunset, and the plane needed to be in the right place at the right time. Venus also goes through phases similar to the Moon, making it difficult to focus the telescope on the planet. Its proximity to the Sun in the sky also complicates matters.
Despite the group finding no phosphine , the study was a success. Together with complementary data from other observatories that vary in depths exploring Venus ‘s atmosphere, SOFIA ‘s results help build the body of evidence against phosphine anywhere in Venus ‘ atmosphere , from its equator to its junctions. poles.
SOFIA was a joint project of NASA and the German Space Agency (DLR). It achieved its full operational capacity in 2014 and completed its last scientific flight on September 29, 2022. (Europa Press)