The path the James Webb Space Telescope follows to discover life on other planets

in it Searching for extraterrestrial life forms or their signatures In distant worlds, the mighty James Webb Space Telescope Follower a pot I managed to create Chemical formula Which can identify exoplanets High odds of being habitable.

Using JWST, Scientists from the Massachusetts Institute of Technology (MIT) and the University of Birmingham It has been stated that the best opportunity for astronomers finding liquid water, and even life on other planets, It is the search for the absence, not the presence, of a chemical property in its atmosphere.

Researchers suggest so If the terrestrial planet had much less carbon dioxide in its atmosphere Compared to other planets in the same system, this could be a sign of liquid water (and perhaps life) on the surface of that distant planet. This new signal, of relatively depleted carbon dioxide, they claim The only sign of habitability that can be detected using the technology we have now.

“The Holy Grail in exoplanetary science is the search for habitable worlds and the presence of life, but all the features that have been talked about so far are beyond the reach of the most modern observatories. But we now have a way to find out if there is liquid water on another planet,” astronomer Julian said. “This is something we can get to in the coming years,” said De Wit, professor of planetary sciences at MIT and co-author of the study. published Recently in the magazine Nature astronomy.

Consult him information About this discovery relevant, astronomer Claudio MartinezHe explained that “the terrestrial planets are outside the Earth, which are located in the Sun’s zone or zone of life, basically Mars and Venus, which have a lot of carbon dioxide in their atmospheres“.

“The point is that The Earth does not own it and one of the mechanisms for taking it is the oceans That sucks it. This study indicates that the decrease in carbon dioxide assumes the presence of water on the planet, and this assumes that this water can support life. Martinez explained: In short, there are a lot of assumptions.

And he added:This does not mean that you will find a planet with low carbon dioxide and you can immediately conclude that it contains life. There are actually other, better ways to deduce this, but as of now we don't have the technology available to do so. Since James Webb can detect these drops of carbon dioxide, the possible presence of the ocean can be assumed. But the truth is that “It's a shot in the dark” Precisely because it would not determine anything about the real existence of life on a planet with low carbon dioxide.

So far, Astronomers discovered More than 5580 scientists outside our solar system. Using current telescopes, astronomers can directly measure a planet's distance from its star and the time it takes to complete one orbit. Those The measurements can help scientists deduce whether the planet is within a habitable zone. But there is no way to directly confirm whether the planet is actually habitable, meaning liquid water exists on its surface.

Throughout our solar system, scientists can discover… The existence of liquid oceans monitoring “Sparkle”. They are flashes of sunlight reflected on liquid surfaces.

These flashes, or specular reflections, have been observed, for example, in Titan, the largest moon of SaturnWhich helped confirm the existence of large lakes on that moon. Likewise, subsequent studies and even NASA missions sent to study this world indicated that methane oceans, not water, are abundant there.

However, detecting a similar glow on distant planets is beyond the reach of current technologies. But de Wit and his colleagues realized that there was another habitable feature close to home that could be discovered on distant worlds.

“We came up with the idea by looking at what happens to terrestrial planets in our own system“Venus, Earth, and Mars share similarities, as all three are rocky and live in a relatively temperate zone relative to the Sun, and Earth is the only planet of the trio that currently hosts liquid water,” says Triode. Carbon dioxide in its atmosphere.

“We assume that these planets were created in a similar way, and if we now see a planet with less carbon, then this element must have gone somewhere. The only process that can remove this amount of carbon from the atmosphere is A powerful water cycle involving oceans of liquid water.

The Earth's oceans play an important and sustainable role in absorbing carbon dioxide. Over hundreds of millions of years, the oceans absorbed a huge amount of carbon dioxide, roughly equivalent to the amount found today in the atmosphere of Venus. This planet-wide effect has left Earth's atmosphere significantly depleted of carbon dioxide compared to its planetary neighbors.

“On Earth, a significant portion of atmospheric carbon dioxide has been sequestered in seawater and solid rock over geological timescales, helping to regulate climate and habitability for billions of years,” said study co-author Frieder Klein.

The team thought so If a similar depletion of carbon dioxide were discovered on a distant planet, For its neighbours, this would be a reliable signal of liquid oceans and life on its surface. “After an extensive review of the literature in many fields, from biology to chemistry and even carbon sequestration in the context of climate change, we believe that, in fact, if we detect carbon depletion, there is a good chance that it will be a strong sign of water,” De Wit said. Liquid and/or life.”

In their study, Team A Strategy for discovering habitable planets By looking for signs of carbon dioxide depletion. Such research would work best for “peas in a pod”-type systems, where multiple terrestrial planets, all roughly the same size, orbit relatively close to each other, similar to our solar system. The first step the team suggests is Ensure that planets have atmospheres, It simply looks for the presence of carbon dioxide, which is expected to dominate most planetary atmospheres.

“Carbon dioxide is an extremely strong absorber in the James Webb infrared vision and can be easily detected in the atmospheres of exoplanets. And The carbon dioxide signal may reveal the existence of exoplanetary atmospheresDe Wit explains.

Once astronomers determine that several planets in the system host atmospheres, they can move on to measuring their carbon dioxide content, to see if one planet has much less than the others. If so, the planet is likely habitable, meaning it hosts large amounts of liquid water on its surface.

Likewise, habitable conditions do not necessarily mean that the planet is inhabited. To find out if life could actually exist, the team suggests that astronomers look for another feature in the planet's atmosphere: Ozone.

On land, researchers have noted that plants and some microbes contribute to carbon dioxide removal, although not to the same extent as the oceans. However, as part of this process, life forms emit oxygen, which reacts with photons from the sun to turn into… Ozone, a molecule that is easier to detect than oxygen itself.

If a planet's atmosphere shows signs of ozone and depleted carbon dioxide, it is likely a habitable world, researchers say. “If we see ozone, there's a good chance it's related to the carbon dioxide that life consumes. And if it's life, it's glorious life. It's not going to be just a few bacteria. It's going to be biomass on a planetary scale capable of processing a huge amount,” Treaud said. of carbon and interaction with it.

The equipment used by the Spanish Telescope James Webb of NASA has a carbon dioxide medium, and is possible in the ozono, in the multiplanetary system of cercanos como TRAPPIST-1, a system of 7 planets that orbit una estrella brillante, a single 40 years old. the earth.

“TRAPPIST-1 is one of the few systems with which we can conduct studies of the Earth's atmosphere using the James Webb Space Telescope. We now have a road map for finding habitable planets. If we all work together, in the coming years we will be able to achieve Paradigm-changing discoveries.