List of potentially habitable exoplanets

This list shows exoplanets that could possibly be habitable. Most of the entries come from estimates made by the Habitable Worlds Catalog (HWC), along with data from the NASA Exoplanet Archive. The HWC is maintained by the Planetary Habitability Laboratory at the University of Puerto Rico at Arecibo.

Scientists think that planetary habitability needs a special kind of orbit. A planet must be at the right distance from its host star so that liquid water can exist on its surface. Other things matter too, such as geophysical and geodynamical features, the density of the atmospheric layer, and the type and strength of radiation. The host star's plasma environment also plays a part.

Main list

This is a dynamic list, so it may never be fully complete. You can help by editing the page to add missing items, with references to reliable sources.

This list shows confirmed exoplanets within the circumstellar habitable zone that are either under 10 Earth masses or smaller than 2.5 Earth radii, so they have a chance of being rocky. Being on the list does not guarantee that a planet is habitable, and larger planets are less likely to be rocky and more likely to be sub-Neptunes. Earth is included for comparison and reference, while Venus and Mars are included for reference only. Values with a "~" have not been measured and are predicted instead.

Current candidates

See also: List of Kepler exoplanet candidates in the habitable zone and Superhabitable world

This is a dynamic list that may never be complete. You can help by editing the page to add missing items, with references to reliable sources.

This is a list of notable planets outside our Solar System that orbit in the circumstellar habitable zone. These planets are either under 10 Earth masses or smaller than 2.5 Earth radii, and they have not yet been confirmed. Earth is included for comparison, while Venus and Mars are included for reference only.

Previous candidates

Some planets found using radial velocity were once considered possibly habitable. Some studies later suggested these signals may have come from the star itself rather than from planets. These include Gliese 581 d and g, Gliese 667 Ce and f, Gliese 682 b and c, Kapteyn b, Gliese 229 Ac, HD 85512 b and Gliese 832 c. Other planets, such as Gliese 180 b, were also once considered potentially habitable but were later found to lie closer to their star than the habitable zone. Tau Ceti e, HD 85512 b and Kepler-69c were also thought to be likely habitable, but with improved models of the habitable zone, PHL no longer considers them potentially habitable. Kepler-438b was first considered potentially habitable too, but it was later found to be hit by powerful flares that can strip a planet of its atmosphere, so it is now considered non-habitable.

K2-3d and K2-18b were first considered potentially habitable. K2-18b remains listed in the HWC, but recent studies have shown that both are gaseous sub-Neptunes rather than the Hycean planet type, so they are unlikely to be habitable. Kepler-1638b was thought to be a possibly habitable planet smaller than 2 Earth radii. Later measurements of the star's distance from Gaia showed the planet is larger, at 3.226 Earth radii, which makes it more likely an ice giant like Neptune with poor chances of habitability. KOI-1686.01 was also considered potentially habitable after it was detected in 2011, until NASA showed in 2015 that it was not a real planet. Kepler-577b and Kepler-1649b were also considered potentially habitable before they were confirmed, but new data show they are no longer considered habitable. TRAPPIST-1 d was considered potentially habitable until JWST/NIRSpec data found little evidence for an atmosphere with Earth-like surface pressure, which made habitability very unlikely.

Extrasolar candidates for liquid water

Scientists have not yet confirmed that liquid water exists anywhere beyond Earth. Most known extrasolar planetary systems seem very different from the Solar System, though this may partly be because of sampling bias from the detection methods used. Current searches aim to find Earth-sized planets in the habitable zone of their systems, also called the Goldilocks zone. Some planets with oceans might be Earth-sized moons of giant planets, but whether such moons really exist is still a guess. Evidence suggests that rocky planets with water may be common throughout the Milky Way galaxy. In June 2020, NASA scientists reported that exoplanets with oceans may be common there, based on mathematical modeling studies.

The list below includes candidates that meet several rules. Each must be a confirmed object at least as heavy as Earth, orbiting in the habitable zone, and must not be a star. It must have been studied for more than a year, have a confirmed surface that is solid or liquid, show water vapour in its atmosphere, and be predicted by models to have a wet layer. Proxima Centauri b is the nearest known exoplanet and is in the habitable zone of its host star, and it might contain liquid water. More details are needed to judge its habitability. Gliese 667 Cc circles a dim red star in 28 days and receives 90% of the light that Earth gets, mostly as infrared light. It is expected to absorb about the same energy from its star as Earth absorbs from the Sun, which could allow temperatures similar to Earth's and perhaps liquid water. The list also includes Kepler-22b, Kepler-62e, which is one of two planets in Kepler-62 at a distance that could allow liquid water, and Kepler-62f, which is only 40 percent larger than Earth. LHS 1140 b was first thought to hold a lot of water and may be an ocean world, though a later study found it to be lighter than first thought and possibly a dense mini-Neptune. JWST observations rule out a hydrogen-rich atmosphere, which supports the ocean world idea. Finally, the list includes TRAPPIST-1e, TRAPPIST-1f, and TRAPPIST-1g.