Astronomers Detect Atmosphere on Habitable-Zone Exoplanet

Astronomers have announced the first clear detection of an atmosphere surrounding a rocky planet located within the habitable zone of a distant star, marking a significant milestone in the search for worlds capable of supporting life. The planet, known as LHS 1140 b, is approximately 48 light-years from Earth and orbits a small, cool red dwarf star in the constellation Cetus.

The findings, published in the journal Science on July 16, 2026, are based on observations from the Magellan Clay telescope at Las Campanas Observatory in Chile. Researchers detected helium escaping from the planet's upper atmosphere, providing direct evidence of a gaseous envelope. This is the first time an atmospheric species has been directly identified on any rocky exoplanet, and the first such detection for a rocky world within its star's habitable zone-the region where temperatures could allow liquid water to exist on the surface.

Lead author Collin Cherubim, a postdoctoral fellow at Harvard University, stated that the discovery confirms LHS 1140 b possesses the three key ingredients considered essential for habitability: a rocky composition, a temperature suitable for liquid water, and a protective...