By Lily Bourne
A Cambridge research team recently discovered signs of dimethyl sulfide and dimethyl disulfide in the atmosphere of K2-18b, a planet in the Goldilocks zone seven hundred trillion miles away. While this sounds completely irrelevant and boring, it actually may come to form the basis of the answer to one of humanity’s biggest questions: is there life in space?
K2-18b has been acknowledged as one of the planets closest to Earth that has the ability to sustain life. Scientists continue to argue over its makeup, some believing it to have a vast liquid ocean, while others believe the planet features an ocean of molten rock. Other researchers even believe the planet is a mini gas giant.
This new finding excited researchers because, on Earth at least, dimethyl sulfide and dimethyl disulfide are only produced by living organisms–specifically, marine phytoplankton and bacteria. Not only that, the concentration of the gases detected in K2-18b’s atmosphere was 1000 times higher than that of Earth’s. Professor Madhusudhan, the lead researcher at Cambridge, explains that “if the association with life is real, then this planet will be teeming with life.”
Now, the scientists must prove their findings through peer-reviewed scientific analysis. They will have to rule out the possibility that the DMS and DMDS could have been formed by non-biological processes. Using the information gathered from the James Webb Space Telescope, they encourage other scientists to review and test their calculations, which will be released publicly soon. The problem, explains Professor Oliver Shorttle of Cambridge University, is that “everything we know about planets orbiting other stars comes from the tiny amounts of light that glance off their atmospheres. So it is an incredibly tenuous signal that we are having to read, not only for signs of life, but everything else.” These new findings contribute stronger evidence to the team’s years-long research on the plane with a 99.7% chance of accuracy, far outperforming their previous attempts from 18 months ago that yielded only 68% chance. However, scientists must be 99.99999% sure that results are correct before they trust the data.
Scientists will continue to search for signs of life on planets outside our solar system, using the James Webb Space Telescope’s incredible technology to learn about their atmospheres from billions of miles away. Following their research of K2-18b, the Cambridge team hopes to strengthen their findings and bolster the hypothesis that life could exist outside of Earth.