Astronomers report that DNA contains an amino acid found in the Venusian atmosphere. – tech2.org

Astronomers report that DNA contains an amino acid found in the Venusian atmosphere.


Does it seem that everyone’s eyes are on Venus these days? The discovery of a possible biomarker phosphine in the planet’s upper atmosphere last month attracted a lot of attention, as it should. Although there is still some uncertainty as to what the discovery of phosphine means.

Now a team of researchers claim that they have discovered the amino acid glycine in the atmosphere of Venus.

The paper announcing the discovery is titled ‘Finding the simplest amino acid glycine in Venus’ environment’. The lead author Arijit Manna, a Ph.D. Research Scholar in the Physics Department at Midnapore College in West Bengal, India. The paper is on the pre-print site arxiv.org, meaning it has not been peer-reviewed and has not yet been published in any journal.

There are approximately 500 known amino acids, but only 20 are present in the genetic code. Glycine is the simplest of them.

Although glycine and other amino acids are not biosignes, they are some of the building blocks of life. In fact, they are 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.

Researchers used the Atacama Large Millimeter / Submillimeter Array (ALMA) to detect glycine in Venus’s atmosphere with a microscope. They found it in the middle latitudes, near the equator. This is where the signal was strongest, and none were found at the poles.

In their paper, the authors write “Detecting it in the Venusian atmosphere may be one of the keys to understanding the formation mechanisms of prebiotic molecules in the Venusian atmosphere. The Venusian upper atmosphere may be undergoing almost the same biological method. Earth billions of years ago. ”

Those two sentences packed an actual punch. Can any biological process run in Venus’s clouds? This “may” be one of the keys, and it “may be” through the same thing that Earth did. what does this mean?

Phosphine first, 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 more strongly detected at mid-latitudes. Phosphine can be a biology and is on Earth. But it can also be made chemically, although it requires huge amounts of energy. It has been found on Jupiter and Saturn, where there is abundant energy for its production. But Venus does not have the energy required to make it.

Phosphine was discovered by the team of researchers that circled in relation to their own findings. In his research paper, he almost begged other researchers to calculate the presence of phosphine without invoking life. “Now, astronomers will think of all the ways to justify phosphine without life, and I welcome it. Please do, because we are at the end of our possibilities to show abiotic processes that can make phosphine.”

Then a few weeks later, another team of researchers did the same. In his paper, called a hypothesis perspective, he stated that volcanoes may be responsible for phosphine.

“We speculate that the amount of phosphide formed in the mantle will be brought to the surface by the volcano, and then subsequently ejected into the atmosphere, where they can react with water or sulfuric acid to form phosphine. Can be made. ”

Phosphine detection forms the backdrop of this latest discovery. Both discoveries are part of the larger questions surrounding Venus: is there a possibility of her life or life on Venus? Or are these chemicals unrelated to life?

Researchers have identified a region of Venus’s atmosphere that may be capable of hosting life. This would be a bizarre and unusual arrangement from our point of view.

Venus is extremely inauspicious for the most part. The atmosphere is acidic, the temperature is hot enough to melt the spacecraft, and the atmospheric pressure is crushing. But high in the clouds, between 48 and 60 km (30 and 37 mi) above the surface, the temperature is not so deadly.

At that altitude, the temperature ranges from −1 C to 93 C (30 to 200 ° F). This is very controversial, but some scientists believe that without touching the surface of the planet, a kind of ordinary life can always live. Phosphine rotates easily, so it must be produced continuously to detect it. Life at that height can be a source of phosphine.

This new discovery of glycine only adds mystery and uncertainty. In their paper, the researchers proposed that Hadley cells may be responsible for providing a home for life.

“Headley circulation of mid-latitudes can give the most stable life-supporting condition with a circulation time of 70–90 days (Earth-like) microbial life is sufficient for reproduction.”

In addition, glycine detection reveals phosphine. “Latitude dependent distribution (about? 10?) Of glycine with the recently identified phosphene detection limit and the proposed upper Headley-cell boundary where the gas rotates between the upper and lower elevations.”

Do not launch spacecraft yet

While worthy of a deeper search and more study, the presence of glycine is close to a knockout setback in the quest to find life nowhere else. Writers know this and are careful to point it out.

“It should be noted that the detection of glycine in the Venusian atmosphere is an indication of the existence of life, but not strong evidence.”

It is a component that uses life, but is not a sign of life.

His papers point to some historical experiments designed to test the chemical origins of life on Earth. In 1953, the now famous Miller-Ure experiment recreated the initial conditions on Earth. The researchers created a chemical mixture of water, methane, ammonia and hydrogen and then applied energy to mimic electricity. The result was a soup of more complex organic compounds.

The experiment produced glycolic acid, a precursor to glycine, and the results supported the abogenesis theory. Glycine found in Venus’s atmosphere could have been generated through a pathway similar to the Miller-Ure experiment. Glycine also has other chemical pathways that are possible in the Venusian atmosphere.

MuexperimentA simple illustration of the Miller-Ure experiment. (By Canny / Hebrew Wikipedia / CC 2.5)

“In astrophysics, chemical physics and biophysics, the synthetic reaction pathways from simple molecules to the simplest amino acid glycine have great significance with chemical evolution and the origin of life,” the authors write.

“The detection of glycine in Venus’s atmosphere may indicate the existence of an early form of life in the solar planet’s atmosphere as amino acids are a building block of proteins. Venus may be undergoing a primary phase of biological evolution.”

Or it may not be.

“Although in Earth, glycine is generated by biological processes, it is possible that glycine in Venus is produced by other photochemical or geochemical means, not on Earth.” Venus is very different from Earth, and there are processes that do not exist here on Earth.

Here is where everyone comes into caution.

The paper has not yet been reviewed. And there are some weaknesses in the results.

For example, the spectroscopic signal of glycine is very close to that of sulfur oxide, so there is an error in the detection of glycine. And this is the only detection, not duplicate or verified. In addition, glycine is the simplest of amino acids and has been found elsewhere. It has been found on comets and meteorites, where there is really no hope of life.

It has not been seen on any planet other than Earth, meaning that it would be surprising to see a world as hostile as Venus.

To find this out, we need more spacecraft orbiting Venus. “A Venus mission can confirm the source of glycine in the planet with direct sampling from the planet’s surface and cloud,” the author says.

The identification of glycine, if confirmed, is another intriguing development in the quest to understand the rise of life. Or it may be showing us that chemistry that appears to be prebiotic is only prebiotic in rare cases, and the rest of the time, it means nothing. There is a lot that we do not know, and the mission for Venus is the only way to get more information and answer some of our questions.

But for now, we can be sure that life is not found on Venus. Instead, we have uncovered just one more piece of the puzzle which is the complex environment of Venus.

This article was originally published by Universe Today. Read the original article.

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