For the first time ever, scientists have confirmed the presence of an atmosphere around a rocky exoplanet located in the habitable zone of its own star, 49 light years from Earth.
“This is the first truly observationally confirmed atmosphere around a rocky planet located in a habitable zone, outside of our solar system,” said Dr. Collin Cherubim, first author of the study, reported The Guardian THURSDAY.
Named LHS 1140b, the exoplanet is similar to Earth in its overall composition and temperature, although it would have a mass 5.6 times greater than that of our planet, and a radius 70% greater, we can read.
First discovered in 2017, scientists first observed a leak of helium escaping from the planet, using an infrared spectrograph mounted on the Magellan Clay telescope at the Las Campanas Observatory in Chile in 2024.
Then, in 2025, upon observing it again, the helium leak no longer appeared to the observers’ surprise, meaning the atmosphere of LHS 1140b is dynamic and responds to its sun; when bombarded with ultraviolet light and heated, the helium leaks, but when the star calms down, the leak stops and becomes invisible from Earth.
Thus, the exoplanet would have all the necessary ingredients for a habitable environment: a rocky planet, a temperature allowing the presence of liquid water and an atmosphere that prevents water from escaping and protects the planet’s surface.
“So it’s a really exciting place to continue research, in particular to look for signs of life,” the researcher told the British media.
According to scientists, however, it could house much more water and have an atmosphere very different from ours, in addition to rotating synchronously, that is to say always showing the same face to its sun, like the Moon facing the Earth.
“It brings LHS 1140b to the forefront as the ideal laboratory – the most promising and fascinating – for studying astrobiology and habitability outside our solar system,” Dr. Cherubim told the British media.
Along the way, the research team confirmed that no atmosphere was detected around its neighbor, LHS 1140c, which orbits the same star.
