Scientists found the most promising evidence, to date, of life on a distant planet
Tentative
Scientists have found tentative evidence, but the most promising yet, of life on another planet. They published their findings in The Astrophysical Journal Letters.
K2-18b
A Cambridge team was responsible for the discovery. Using data from NASA's James Webb Space Telescope, they found possible traces of life on planet K2-18 b, 124 light-years away.
Image: NASA / Exoplanet Catalog (Screenshot)
Chemical analysis
The data came from a chemical analysis of the planet's atmosphere. The Guardian explained that the telescope gathered wavelength data when the planet passed before its star.
Two molecules
It registered the wavelengths of two molecules: dimethyl sulfide (DMS) and dimethyl disulfide (DMDS), which are produced only by living organisms on Earth.
Phytoplankton
The evidence suggested that the presence of DMS and DMDS in K2-18b's atmosphere is thousands of times stronger than that of Earth, where phytoplankton produces most of them.
A massive planet
K2-18b is a massive planet, with nine times the mass of the Earth and 2.6 times its size. It orbits a cool red dwarf star less than half the size of the Sun, the Guardian said.
In the habitable zone
It is also within its solar system's inhabitable zone. The researchers believe the planet is covered by vast oceans, but others challenge that notion, according to the newspaper.
Second evidence
The Cambridge team has studied K2-18b for years. In 2019, they said the atmosphere contained water vapor, but it turned out to be methane. Still, the team believes it is a promising candidate for life.
"Within a year or two"
"This is the strongest evidence that there is possibly life out there. I can realistically say that we can confirm this signal within one to two years," Professor Nikku Madhusudhan, one of the authors, told the BBC.
Skeptics
However, other researchers are more skeptical about the possibility of life in K2-18b and about DMS and DMDS being proof. One of them is Dr. Nora Hänni, a chemist at the University of Berne.
Only one of the options
"Life is one of the options, but it's one among many. We would have to strictly rule out all the other options," Dr. Hänni told The Guardian. Her research revealed that DMS was also present on a lifeless, icy comet.
