For years, methane has been considered a biosignature that may indicate life on alien planets. However, this unique compound has biotic and abiotic sources. Therefore, even if scientists find it in the atmosphere of another world, this does not mean that there must be life there. However, even if it does not herald the activity of living organisms, it may reveal the course of specific and unique geological or chemical processes.
The discovery of this compound prompts researchers to deepen their analysis, and methane is even considered an “aphrodisiac” for astronomers. It remains in the planet’s atmosphere for a short time because (at least in Earth’s atmosphere). Photodissociation (The disintegration of molecules under the influence of photons). Therefore, in order to exist in the air/atmosphere, it must be constantly replenished.
As scientists point out, if a rocky planet contains significant amounts of methane, its source must be “massive,” making the existence of present-day life more likely.
Astronomers using James Webb Space TelescopeMethane gas was detected in the atmosphere of the planet WASP-80b. This planet is a gas giant with a mass half that of Jupiter, and it is much warmer. The age of the star it orbits is about 1.5 billion years and is classified as type K. The planetary system is about 162 light-years away from us.
As scientists point out, that’s why WASP-80b is a gas giantThe existence of life as we know it is unlikely. Although such scenarios do occur in science fiction movies.
On rocky planets, the source of methane is in the atmosphere, as well as biotic sources, among other things. serpentine, which is a natural and abiotic process involving water, carbon dioxide, and, among others, olivine (minerals). This process is not responsible for the presence of methane on WASP-80b. Therefore, the presence of this compound on this exoplanet is very interesting.
“The definitive detection of methane in the atmosphere of WASP-80b using low-resolution JWST spectroscopy raises the question of how much previous non-detections have been influenced by the sparse wavelength coverage and resolution that can be achieved using HST and Spitzer,” the authors of the latest research wrote. analysis.
Now researchers are wondering whether we will continue to detect methane on alien worlds (including gas giants). Whether it will be necessary to change our thinking about methane as a biosignature remains to be seen.
“As we find methane and other gases on exoplanets, we will continue to expand our understanding of how chemistry and physics work under conditions different from those on Earth, and perhaps soon on other planets reminiscent of what we have here at home.” “, the astronomers added on NASA’s blog.
Even if it turns out in the future that methane will no longer be understood as a biosignature, its discovery will still be very important. As the researchers wrote: “By measuring the amount of methane and water on the planet, we can infer the ratio of carbon atoms to oxygen atoms. This ratio is expected to change depending on Where and when will the planets form? In its order.”
The next step for astronomers will be to analyze WASP-80b using different wavelengths, which will allow other particles to be etched. The scientists explain: “Our findings lead us to believe that we will be able to monitor others Carbon-rich molecules“Such as carbon monoxide and carbon dioxide, which will allow us to paint a more complete picture of conditions in the planet’s atmosphere.”
One thing is clear: the discovery using the James Webb Space Telescope is full of potential surprises, the authors say. The research results were published in the magazine nature.
