Trappist-1 system consists of seven Earth-sized planets orbiting a red dwarf star located about 40 light-years away. The system has garnered interest due to the potential habitability of some of its planets. However, a recent study suggests that these planets are unlikely to support life and have likely lost their atmospheres over time.
Red dwarf stars like TRAPPIST-1, which are cooler than the Sun, present challenges for habitable planets. These stars emit intense solar flares and high-energy radiation that can strip away the atmospheres of nearby planets. Despite the initial excitement about the potential habitability of the TRAPPIST-1 system, the new study indicates that the planets within this system have likely been stripped of their atmospheres and may be barren.
Recent observations from the James Webb Space Telescope (JWST) have confirmed that the two innermost planets of the TRAPPIST-1 system lack significant atmospheres, similar to Mercury in our own solar system. The study utilized computer simulations to estimate the atmospheric evaporation of the outer planets in the TRAPPIST-1 system based on the high-energy radiation emitted by the star. The results suggest that even the outer planets would have lost an Earth’s atmosphere worth of gases within a few hundred million years, indicating a rapid rate of atmospheric loss.
The findings have implications not only for the TRAPPIST-1 system but for other planetary systems orbiting red dwarf stars. Given that red dwarfs constitute a substantial portion of stars in the galaxy, the potential for habitable worlds may be limited if these stars are prone to stripping away planetary atmospheres. This raises significant questions about the prevalence of extraterrestrial life in the universe.
The study, “Airy worlds or barren rocks? On the survivability of secondary atmospheres around the TRAPPIST-1 planets,” provides insights into the potential habitability of exoplanetary systems and highlights the challenges posed by red dwarf stars in sustaining atmospheres on their orbiting planets.
