Astronomers have announced the first detection of an atmosphere surrounding a rocky planet situated within its star’s habitable zone. This discovery concerns LHS 1140 b, classified as a “super-Earth.” The finding marks a significant milestone in the search for exoplanets potentially capable of supporting life. Previously, atmospheric detections had been limited to gas giants.
According to the study published in Science, the search for life-supporting worlds focuses on planets with terrestrial compositions located at distances allowing for liquid water. LHS 1140 b has a mass five times that of Earth and a radius 1.7 times that of Earth, suggesting a rocky core, while its lower density implies the presence of a thin atmosphere and possibly water. Researchers utilized the WINERED spectrograph at the Las Campanas Observatory in Chile, observing the planet during a transit in September 2024.
By analyzing the light passing through the atmosphere, scientists confirmed signs of a helium-dominated atmosphere that is escaping into space. A key aspect of this finding is that LHS 1140 b has managed to retain this atmosphere for over three billion years, despite the intense radiation emitted by its host red dwarf star. Scientists note that while the planet receives only about 42% of the energy Earth gets from the Sun, it has maintained atmospheric integrity.
This confirmation of a helium-rich atmosphere, predicted by modeling planetary mass loss, underscores the potential for such worlds. Further analysis will concentrate on identifying features that could indicate the presence of liquid water or other life-sustaining elements. The successful observation using ground-based equipment also emphasizes the vital role of terrestrial observatories alongside space telescopes in exoplanetary research.
Topics: #habitable #planet #discovery
