Astronomers Report They’ve Detected the Amino Acid Glycine in the Atmosphere of Venus
Posted on October 15, 2020 by Evan Gough
Does it feel like all eyes are on Venus these days? The discovery of the potential biomarker phosphine in the planet’s upper atmosphere last month garnered a lot of attention, as it should. There’s still some uncertainty around what the phosphine discovery means, though.
Now a team of researchers claims they’ve discovered the amino acid glycine in Venus’ atmosphere.
The paper announcing the finding is titled “Detection of simplest amino acid glycine in the atmosphere of the Venus.” The lead author is Arijit Manna, a Ph.D. Research Scholar in the Dept. of Physics at Midnapore College in West Bengal, India. The paper is at the pre-print site arxiv.org, which means it hasn’t been peer-reviewed and published in a journal… yet.
There are about 500 known amino acids, but only 20 are present in the genetic code. Glycine is the simplest of them.
Though glycine and other amino acids aren’t biosignatures, they are some of the building blocks of life. In fact, they’re the building blocks of proteins. They were also some of the first organic molecules to appear on Earth. Glycine is important for the development of proteins and other biological compounds.
The researchers used the Atacama Large Millimeter/submillimeter Array (ALMA) to detect glycine in Venus’ atmosphere with spectroscopy. They found it in the mid-latitudes, near the equator. That’s where the signal was strongest, and there was none detected at the poles.
In their paper, the authors write “Its detection in the atmosphere of Venus might be one of the keys to understanding the formation mechanisms of prebiotic molecules in the atmosphere of Venus. The upper atmosphere of Venus may be going through nearly the same biological method as Earth billions of years ago.”
Those two sentences pack a real punch. Could there be some kind of biological process going on in the clouds of Venus? It “might” be one of the keys, and it “may be going” through the same thing Earth did. What does it mean?
First Phosphine, Then Glycine
In mid-September, a team of researchers reported finding phosphine in the upper atmosphere of Venus (Greaves et al, 2020). Like glycine, it was also detected more strongly at mid-latitudes. Phosphine can be a biosignature and is on Earth. But it can also be created chemically, though that requires an enormous amount of energy. It’s been detected at Jupiter and Saturn, where there’s abundant energy for its production. But Venus doesn’t have the required energy to create it.
That team of researchers that discovered phosphine was circumspect with regards to their own findings. In their paper, they almost pleaded with other researchers to account for phosphine’s presence without invoking life. “Now, astronomers will think of all the ways to justify phosphine without life, and I welcome that. Please do, because we are at the end of our possibilities to show abiotic processes that can make phosphine.”
Then a couple of weeks later, another team of researchers did just that. In their paper, called a hypothesis perspective, they said that volcanoes could account for the phosphine. “We hypothesize that trace amounts of phosphides formed in the mantle would be brought to the surface by volcanism, and then subsequently ejected into the atmosphere, where they could react with water or sulfuric acid to form phosphine.”
The detection of phosphine forms the background for this latest discovery. Both discoveries are part of the larger questions around Venus: Is their life or the potential for life at Venus? Or are these chemicals unrelated to life?
Researchers have identified a region of Venus’ atmosphere that might be able to host life. It would be a bizarre and unusual arrangement from our perspective.https://www.universetoday.com/148345/astronomers-report-theyve-detected-the-amino-acid-glycine-in-the-atmosphere-of-venus/