NASA's James Webb Space Telescope has potentially discovered evidence of a sign of life on a distant planet. The telescope detected a molecule called dimethyl sulphide (DMS), which on Earth is only produced by life. However, researchers emphasize that the detection on the planet, named K2-18b, is not yet confirmed and more data is needed. Methane and CO2 have also been detected in the planet's atmosphere, which could indicate the presence of a water ocean.
The discovery of DMS on a planet orbiting a distant star is a first for astronomers, but caution is still being exercised due to a previous disputed claim about the presence of another molecule, phosphine, on Venus. Despite this, independent expert Dr. Robert Massey expressed excitement about the results and the possibility of finding signs of life in the future.
The James Webb Space Telescope is able to analyze the light passing through the planet's atmosphere, revealing the chemical signature of molecules present. This feat is remarkable considering the planet is over 1.1 million billion km away. In addition to DMS, methane and carbon dioxide were confidently detected through spectral analysis. The proportions of these gases suggest the presence of a water ocean beneath a hydrogen-rich atmosphere.
The planet's ability to support life depends on factors such as temperature, carbon presence, and potentially liquid water. K2-18b appears to meet these criteria, but the possible presence of DMS is particularly intriguing. What sets this planet apart is its size, being nearly nine times larger than Earth. These "sub-Neptunes," which are planets between the size of Earth and Neptune, are not well understood and differ from anything in our solar system. Dr. Subhajit Sarkar of Cardiff University notes that sub-Neptunes are the most common type of planet known in the galaxy.
While the discovery of DMS on K2-18b is not yet confirmed, it represents an exciting step towards understanding the potential for life on other planets. The ongoing research and analysis conducted by the James Webb Space Telescope provide valuable insights into the composition and atmospheres of distant exoplanets.