Utilizing data from ESA’s Gaia mission and NASA’s Exoplanet Archive, astronomers at Cornell University have discovered 45 rocky exoplanets in the habitable zone and 24 within the more specific 3D habitable zone. This groundbreaking research aids scientists in their quest for extraterrestrial life.
Artist’s impression of a planetary system around a star slightly hotter than the Sun. Image credit: Gillis Rowley.
“With over 6,000 known exoplanets from successful ground and space investigations, the research landscape has evolved significantly,” said Professor Lisa Kaltenegger of Cornell University and colleagues.
The expanding catalog of exoplanets enables astronomers to compile a targeted list for examining the boundaries of the habitable zone empirically.
This study reveals the identification of 45 rocky worlds that could potentially support life in the habitable zone, with an additional 24 in the narrower 3D habitable zone, suggesting a more cautious view on the heat a planet can endure.
Highlighted exoplanets include notable names such as Proxima Centauri b, Trappist 1f, and Kepler 186f, alongside lesser-known entities like TOI-715b.
Noteworthy planets include TRAPPIST-1d, e, f, g located 40 light-years from Earth, and LHS 1140 b, which is 48 light-years away. The possibility of liquid water on these planets hinges on their capacity to retain atmospheres.
Planets that receive light similar to that of Earth from the Sun are among the transiting candidates TRAPPIST 1e, TOI-715b, Kepler 1652b, Kepler 442b, and Kepler 1544b, as well as the star-wobble planets Proxima Centauri b, Gliese 1061d, Gliese 1002b, and Wolf 1069b.
The researchers also anticipate that planets on the edge of the habitable zone might clarify the limits of habitability and validate current scientific theories.
“Though the habitable zone concept has evolved since the 1970s, new observations are critical for determining whether adaptations are necessary,” stated Professor Kaltenegger.
Diagram displaying the boundaries of habitable zones across various star types, including rocky exoplanets. Image credit: Gillis Lowry / Pablo Carlos Budassi.
Moreover, exoplanets with unique elliptical orbits can monitor how variations in heat affect habitability, providing insights into whether a planet must remain in the habitable zone to sustain life.
Transiting planets useful for assessing habitability at the inner edge include K2-239d, TOI-700e, K2-3d, along with the star-wobble planets Wolf 1061c and Gliese 1061c.
On the outer edges of the habitable zone, planets like TRAPPIST-1g, Kepler-441b, and Gliese 1002c will be critical to exploring colder environments.
“Determining the factors that enhance the likelihood of life is complex, but narrowing down the best targets for observation is an essential first step,” remarked Gillis Rowley, a graduate student at San Francisco State University.
The research team has categorized optimal planets for observational techniques to maximize the chances of detecting signs of life.
This curated list will direct astronomers in their investigations using advanced instruments like the NASA/ESA/CSA James Webb Space Telescope, the future Nancy Grace Roman Space Telescope, the Very Large Telescope, the Habitable World Observatory, and the proposed Large Interferometer for Exoplanets (LIFE) project.
“Observing these small exoplanets is crucial to understanding their atmospheres and refining theories about their habitable zones,” concluded Lowry.
The research team’s paper is published today in the Royal Astronomical Society Monthly Notices.
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Abigail Ball et al. 2026. Exploring the boundaries of the habitable zone: A catalog of rocky exoplanets in the habitable zone. MNRAS 547 (3): stag028; doi: 10.1093/mnras/stag028
Source: www.sci.news
