45 Rocky Exoplanets: Top Targets in the Search for Life Beyond Earth

45 Rocky Exoplanets: Top Targets in the Search for Life Beyond Earth

March 26, 2026 Sarah Wu - Tech Editor Tech and Science

The search for life beyond Earth just received a significant boost, with astronomers identifying nearly 50 rocky exoplanets as prime candidates for harboring habitable conditions. This discovery, detailed in a new study published in Monthly Notices of the Royal Astronomical Society, arrives alongside the release of the Hollywood blockbuster Project Hail Mary, a film that imagines a desperate mission to discover life-sustaining resources on another planet. The timing isn’t lost on researchers, who suggest their findings could inform the kind of interstellar search depicted in the movie, where Ryan Gosling’s character encounters alien life, including a being named Rocky and fictional microorganisms like Astrophage and Taumoeba.

Defining the Habitable Zone

At the heart of this search is the concept of the “habitable zone” – the region around a star where temperatures are just right for liquid water to exist on a planet’s surface. Water is considered essential for life as we currently understand it, making planets within this zone the most promising targets. Professor Lisa Kaltenegger, director of the Carl Sagan Institute at Cornell University, led the research team, which leveraged data from the European Space Agency’s Gaia mission and the NASA Exoplanet Archive to pinpoint these potential havens. The team didn’t just look for planets *in* the habitable zone, but similarly prioritized those receiving stellar energy levels similar to Earth’s, further refining the search.

This isn’t a simple calculation. As the research highlights, the boundaries of the habitable zone shift depending on the type of star. Different wavelengths of light emitted by different stars heat planetary atmospheres in different ways, meaning a planet’s distance from its star isn’t the only factor determining habitability. A diagram illustrating these shifting boundaries is available on the Royal Astronomical Society website.

The List of 45: Promising Worlds

The study identified 45 rocky planets within the habitable zone that could potentially support life. Researchers also narrowed the field further, highlighting 24 planets within a more restrictive “3D habitable zone,” which considers tighter constraints on a planet’s ability to retain heat. Among the most frequently cited candidates are Proxima Centauri b, TRAPPIST-1f, and Kepler 186f, but the list also includes lesser-known worlds like TOI-715 b.

The TRAPPIST-1 system, located about 40 light-years away, is particularly intriguing. Planets d, e, f, and g within this system are considered especially Earth-like. Another promising target is LHS 1140 b, situated 48 light-years from Earth. However, the presence of liquid water on these planets hinges on their ability to maintain an atmosphere – a factor that remains uncertain.

Energy Levels and Nearby Systems

Several of the identified planets receive levels of starlight comparable to what Earth receives from the Sun. These include TRAPPIST-1 e, TOI-715 b, Kepler-1652 b, Kepler-442 b, Kepler-1544 b, Proxima Centauri b, GJ 1061 d, GJ 1002 b, and Wolf 1069 b. The last group are detected through the subtle wobble they induce in their host stars, a technique known as the radial velocity method. ScienceDaily provides a visual representation of the TRAPPIST-1 system, showcasing the arrangement of its planets.

Beyond the Standard Habitable Zone

The research didn’t limit itself to planets squarely within the traditional habitable zone. Scientists also examined planets located near its inner and outer edges, as well as those with highly elliptical orbits. Studying these worlds can help refine our understanding of the limits of habitability. For example, planets with elliptical orbits experience significant temperature fluctuations throughout their year. Determining whether life could survive such variations is a key question.

Planets like K2-239 d, TOI-700e, and K2-3d help scientists explore the inner boundary of habitability, while TRAPPIST-1g, Kepler-441b, and GJ 102 offer insights into the colder outer edge. This approach acknowledges that the concept of a habitable zone isn’t static and can be influenced by a variety of factors.

Observational Tools and Future Prospects

The curated list of 45 planets isn’t just an academic exercise. It’s designed to guide astronomers using current and future telescopes, including the James Webb Space Telescope (JWST), the Nancy Grace Roman Space Telescope (launching in 2027), the Extremely Large Telescope (first light in 2029), the Habitable Worlds Observatory (expected in the 2040s), and the proposed Large Interferometer For Exoplanets (LIFE) project. These instruments will be crucial for analyzing the atmospheres of these planets and searching for biosignatures – indicators of life.

Early analysis of the 10 planets receiving Earth-like radiation has already identified TRAPPIST-1 e and TOI-715 b as strong candidates for near-term study. The TRAPPIST-1 system is already a major focus for JWST observations, led by Cornell astronomer Nikole Lewis. The smaller size of the stars in these systems makes it easier to detect and study their orbiting planets.

What Comes Next: Refining the Search

As Gillis Lowry, a graduate student at San Francisco State University and a co-author of the study, explained, “We wanted to create something that will enable other scientists to search effectively and we kept discovering new things about these worlds we wanted to investigate further.” The team’s work provides a valuable starting point for future research, but it’s important to remember that identifying a planet within the habitable zone is just the first step.

Further observations are needed to determine whether these planets have atmospheres, what those atmospheres are composed of, and whether they contain any signs of life. The James Webb Space Telescope, with its powerful infrared capabilities, will play a critical role in this process. The Nancy Grace Roman Space Telescope, with its wide-field view, will help identify even more exoplanet candidates. And future telescopes, like the Habitable Worlds Observatory, will be designed specifically to search for biosignatures in the atmospheres of potentially habitable planets. SciTechDaily offers an artistic illustration of the TRAPPIST-1 system, highlighting the potential for habitability within this intriguing planetary arrangement.

Full List of 45 Potentially Habitable Exoplanets Identified in the Paper:

  1. GJ 1002 b
  2. GJ 1002 c
  3. GJ 1061 c
  4. GJ 1061 d
  5. GJ 251 c
  6. GJ 273 b
  7. GJ 3323 b
  8. GJ 667 C c
  9. GJ 667 C e
  10. GJ 667 C f
  11. GJ 682 b
  12. K2-239 d
  13. K2-288 B b
  14. K2-3 d
  15. K2-72 e
  16. Kepler-1229 b
  17. Kepler-1410 b
  18. Kepler-1544 b
  19. Kepler-1606 b
  20. Kepler-1649 c
  21. Kepler-1652 b
  22. Kepler-186 f
  23. Kepler-296 e
  24. Kepler-296 f
  25. Kepler-441 b
  26. Kepler-442 b
  27. Kepler-452 b
  28. Kepler-62 e
  29. Kepler-62 f
  30. L 98-59 f
  31. LHS 1140 b
  32. LP 890-9 c
  33. Proxima Centauri b
  34. Ross 508 b
  35. TOI-1266 d
  36. TOI-700 d
  37. TOI-700 e
  38. TOI-715 b
  39. TRAPPIST-1 d
  40. TRAPPIST-1 e
  41. TRAPPIST-1 f
  42. TRAPPIST-1 g
  43. Teegarden’s Star c
  44. Wolf 1061 c
  45. Wolf 1069 b