Astronomers have detected tantalizing hints of life on distant planet K2-18b, with the discovery of molecules that on Earth are only produced by simple organisms.
Scientists have found new but tentative evidence that a faraway world orbiting another star may be home to life. A Cambridge team studying the atmosphere of a planet called K2-18b has detected signs of molecules which on Earth are only produced by simple organisms.
K2-18b is a super-Earth exoplanet located in the constellation Leo.
It orbits a small, cool star about 111 light-years from Earth.
The planet's size and mass suggest it has a thick atmosphere, possibly composed of water vapor and other gases.
This atmosphere could lead to a runaway greenhouse effect, making K2-18b a potentially hostile world.
Scientists study K2-18b to understand the formation and evolution of planetary atmospheres.
The Discovery and Its Implications
Astronomers using NASA’s ‘James Webb Space Telescope (JWST)’ have discovered that the atmosphere of K2-18b contains the chemical signature of at least one of two molecules associated with life: dimethyl sulphide (DMS) and dimethyl disulphide (DMDS). On Earth, these gases are produced by marine phytoplankton and bacteria. The detection is significant as it suggests that this planet may be teeming with life.
Understanding the Detection
The lead researcher, Prof Nikku Madhusudhan, stated that he was surprised by how much gas was detected during a single observation window. The amount estimated in the atmosphere is thousands of times higher than what we have on Earth. If the association with life is real, this planet would be teeming with life. Prof Madhusudhan also believes that if they confirm life on K2-18b, it should basically confirm that life is very common in the galaxy.
Dr. Nishith K. Madhusudhana is an Indian astrophysicist and astrobiologist, currently working as a research scientist at NASA's Ames Research Center.
He earned his Ph.D. in astrophysics from the University of Colorado Boulder.
Madhusudhana's research focuses on exoplanetary atmospheres, habitability, and the search for life beyond Earth.
He has published numerous papers in prestigious scientific journals and is a sought-after expert in his field.
The Scientific Debate
However, there are many ‘ifs’ and ‘buts’ at this stage, as Prof Madhusudhan’s team freely admits. For a discovery to be confirmed, the researchers need to be about 99.99999% sure that their results are correct and not a fluke reading. Currently, the detection is only three sigma, 99.7%, which is not enough to convince the scientific community.
Alternative Interpretations
Other research groups have put forward alternative, lifeless, explanations for the data obtained from K2-18b. There is a strong scientific debate about whether DMS and DMDS are present and also about the planet’s composition. Some researchers infer that the planet has a vast liquid ocean due to the absence of ammonia in its atmosphere, while others suggest it could be an ocean of molten rock.
The Road Ahead
Despite the challenges, Prof Madhusudhan remains optimistic. He believes his team is on the right track and that this discovery could be the tipping point where we can answer one of the biggest questions in science: whether we’re alone in the universe.
Prof. Nikku Madhusudhan is a renowned 'astrobiologist and theoretical physicist.' He has made significant contributions to the field of exoplanetary science, particularly in understanding the atmospheres of distant planets. His work focuses on analyzing the chemical composition of planetary atmospheres to determine their potential for life. Prof. Madhusudhan's research emphasizes the importance of atmospheric chemistry in astrobiology, providing valuable insights into the possibility of extraterrestrial life.
