In more conventional science fiction sagas, aliens usually resemble the living beings we know. Many times, they are even intelligent and walk on solid planets like ours. However, reality can be more strange. With that hypothesis, the astronomer team works, which has just announced what is “the strongest evidence so far” of life outside the earth. Other experts, however, believe it has no data to affirm such a thing.
THE NEW WORLD inhabited It would be, a planet to 120 light years from here similar to Neptune, with twice and a half the size of the earth, orbiting a distance of its star that would allow it to have a liquid water ocean covered by an atmosphere of hydrogen. These worlds, believe Madhusudhan, can be suitable for life. Now, using the , It has detected in that exoplanet two gases, dimethyl sulfide, or DMS, and dimethyl disulfide, or DMDs, which on earth are mainly produced by microbial life such as marine phytoplankton (algae) or bacteria.
“This is a revolutionary moment,” said Madhusudhan in the presentation of the finding, ensuring that “it is the first time that humanity has seen potential biofirms in a habitable planet.” Although he acknowledges that a lot of work is needed to confirm the finding of extraterrestrial life, the researcher believes that the best explanation for his observations is that K2-18B is covered by a temperate and alive ocean.
Despite the excitement shown by their statements, other experts show more caution. Ignasi Ribas, director of the Institute of Space Studies of Catalonia (IEEC) and CSIC research professor, considers that it is an “interesting” discovery, but that it is far from allowing to affirm that life has been found. “It is a single group advertisement, which will have to try to replicate others, it is a very preliminary moment,” he says. The results have been published in the magazine The a minor scientific magazine. These types of results, the sources consulted coincide, to show what the expert says and although they offer a 99.7%security, they should have been published in a first -order magazine such as Science o Nature.
As Ribas recalls, this team is leading research around this exoplanet. In 2019, the presence of water was announced, which finally ended up being methane, and in 2023 a signal that has now been observed with more intensity was now published. “Then, shortly after the finding, articles that explained the presence of the compound in the planet’s atmosphere through mechanisms other than the biological activity and predict that in the coming weeks will begin to happen the same thing began to be published,” adds Ribas.
He James Webb It is such a powerful telescope that it is able to analyze the chemical composition of the atmosphere of a planet through the light of the star that crosses it. With that technique, the atmospheres of planets similar to K2-18B are already being analyzed in search of more similar signals on similar planets that allow us to conclude that it is not an exotic phenomenon that only occurs in one place. “There are many Mijineptuna And that would increase the number of sites in which you can look for life, ”says Ribas.
K2-18 B has 8.6 times the mass of the earth and a diameter approximately 2.6 times greater than that of our planet. Orbite in the “” – a distance where liquid water, a key ingredient for life, can exist on the planetary surface – around a smaller and less bright red dwarf star than our sun, in Leo’s constellation. Another planet has also been identified by orbiting this star.
Madhusudhan believes that if there are these worlds covered by water oceans and a hydrogen -rich atmosphere, they could have a microbial life similar to that observed in the oceans of the earth. It is hypothesized that its oceans are warmer than those of our planet. When asked, in the presentation of this finding, about the possibility of multicellular organisms or even intelligent life, Madhusudhan said: “We cannot answer this question at this time. The starting hypothesis is that of a simple microbial life.”
The scientist mixed his enthusiasm with caution. “First, we need to repeat the observations two or three times to ensure that the signal we observe is robust and increase the significance of detection to the point where the chances of a statistical chance are lower than approximately one million,” he said. “Second, we need more theoretical and experimental studies to determine if there is another abiotic mechanism (which does not involve biological processes) that generates DMS or DMDs in a planetary atmosphere such as that of K2-18 B. While previous studies have suggested them as robust biofirms even for K2-18 B, we must keep the mind open and explore other possibilities,” he concluded. The findings represent great uncertainty about whether the observations are due to the presence of life. “No one is interested prematurely that we have detected life,” warned the scientist.
Other experts demand even more caution. The study finds a “sigma” probability of biological activity, something that, according to experts, is insufficient: at least it should be 5 sigma. David Clements, astrophysicist of the Imperial College of London, has told the United Kingdom SMC portal: “This is really interesting and, although it still does not represent a clear detection of dimethyl sulfide or dimethyl disulfide, it is a step in the right direction. To be able to affirm with certainty the existence of life on this planet, we would need a solid detection, greater than 5 sigma, a clear demonstration of a clear demonstration. Biomarker and not from another molecular species that passes through biomarker.
For his part, Stephen Burgess, group leader at the University of Cambridge (but not of this team), has said to the same medium: “Tres Sigma ‘is a threshold that indicates that the differences observed in the experiment are notable enough to exclude the possibility that they should be randomly due, except in rare cases, equivalent in rareness to launch a coin 10 times and obtain the same result and obtain the same result. A stricter threshold, is equivalent to launching a currency 20 times in a row and obtaining the same result every time.
What happens with this minineptunoin the coming years, thanks to machines like James Webbexperts believe that there are many chances that, if there is extraterrestrial life, their signals reach the earth and are studied by astronomers. But, remember, we are not at that point yet.
