A team led by Professor Lisa Kaltenegger at Cornell University has pinpointed 45 rocky exoplanets in the habitable zones of their stars, where liquid water might exist. The research, drawing on data from ESA's Gaia mission and NASA's Exoplanet Archive, highlights prime targets for the search for extraterrestrial life. Published in Monthly Notices of the Royal Astronomical Society, the study also notes 24 additional candidates in a stricter habitable zone.
Professor Lisa Kaltenegger, director of the Carl Sagan Institute at Cornell University, and her team of researchers, including undergraduate students, analyzed data from the European Space Agency's Gaia mission and the NASA Exoplanet Archive. From over 6,000 confirmed exoplanets, they selected 45 rocky worlds in the habitable zone—a region around stars where conditions could allow liquid water on a planet's surface, essential for life as known on Earth. An additional 24 planets fit within a more conservative three-dimensional habitable zone accounting for tighter heat tolerances. The findings appear in the paper 'Probing the limits of habitability: a catalogue of rocky exoplanets in the habitable zone,' published in Monthly Notices of the Royal Astronomical Society. Kaltenegger linked the work to the film Project Hail Mary, stating, 'Our paper reveals where you should travel to find life if we ever built a 'Hail Mary' spacecraft.' Promising nearby targets include planets in the TRAPPIST-1 system—d, e, f, and g—about 40 light-years away, LHS 1140 b at 48 light-years, Proxima Centauri b, and TOI-715 b. Several receive stellar energy similar to Earth's, such as TRAPPIST-1 e and Kepler-442 b. The list also features worlds with elliptical orbits to test habitability limits, like K2-239 d and TRAPPIST-1 g. Co-author Gillis Lowry, now at San Francisco State University, said, 'Identifying where to look is the first key step.' Lucas Lawrence, at the University of Padua, added that the catalogue enables effective searches. Abigail Bohl emphasized using Venus, Earth, and Mars as benchmarks for atmospheres and energy levels. These targets are observable with telescopes like the James Webb Space Telescope, with TRAPPIST-1 e and TOI-715 b as top priorities.