Produced by: Tarun Mishra Designed by: Manoj Kumar
Since its launch in late 2021, NASA's James Webb Space Telescope (JWST) has aimed to detect potential signs of life on exoplanets, focusing particularly on rocky planets orbiting M-dwarfs, which are low-mass stars and the most common type of stars in the universe.
One of the main targets is TRAPPIST-1, a nearby M-dwarf star located 40 light years away. Its system of orbiting planets is under close examination, with scientists looking for life-supporting atmospheres on planets orbiting stars other than the Sun.
Earlier studies suggested that planets orbiting M-dwarfs, including those in the TRAPPIST-1 system, might not be habitable due to intense UV radiation that could strip away surface water, leaving the planet dry and potentially oxygen-rich, making it unsuitable for life.
A recent study led by the University of Washington, published in *Nature Communications*, models how some rocky planets could develop stable atmospheres over time. The research indicates that these planets may retain gases like water vapor, creating conditions that are more favourable for supporting life.
The study modelled the evolution of rocky planets, showing that although light gases like hydrogen escape early on, planets farther from their stars could react hydrogen with oxygen and iron to form water and heavier gases. This could lead to a stable atmosphere over time.
The research focuses on planets in the "Goldilocks zone"—regions where temperatures allow for liquid water. Planets in these zones may retain their atmospheres, preventing water from escaping, and therefore, increasing their chances of supporting life.
So far, JWST has observed hotter planets close to their stars and found that they likely lack atmospheres. However, the telescope has not yet been able to clearly observe planets in the Goldilocks zone, leaving open the possibility that those planets might still have atmospheres capable of supporting life.
The study suggests that it is crucial to continue using current telescopes like JWST, as well as upcoming ground-based telescopes, to study the atmospheres of these planets. The findings highlight the potential of rocky planets around M-dwarfs to support life, and the importance of ongoing scrutiny of these systems.