Astronomy:List of potentially habitable exoplanets

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Short description: Overview of potentially habitable terrestrial exoplanets

This is a list of potentially habitable exoplanets. The list is mostly based on estimates of habitability by the Habitable Exoplanets Catalog (HEC), and data from the NASA Exoplanet Archive. The HEC is maintained by the Planetary Habitability Laboratory at the University of Puerto Rico at Arecibo.[1] There is also a speculative list being developed of superhabitable planets.

Surface planetary habitability is thought to require to orbit at the right distance from the host star for liquid surface water to be present, in addition to various geophysical and geodynamical aspects, atmospheric density, radiation type and intensity, and the host star's plasma environment.[2]

List

This is a list of exoplanets within the circumstellar habitable zone that are under 10 Earth masses and smaller than 2.5 Earth radii, and thus have a chance of being rocky.[3][1] Note that inclusion on this list does not guarantee habitability, and in particular the larger planets are unlikely to have a rocky composition.[4] Earth is included for comparison.

Note that mass and radius values prefixed with "~" have not been measured, but are estimated from a mass-radius relationship.

Object Star Star type Mass (M) Radius (R) Density (g/cm3) Flux (F) Teq (K) Period (days) Distance (ly) Refs/Notes
Earth Sun Template:StarG 1.00 1.00 5.514 1.00 255 365.25 0 Reported for reference. Only planet known to support life.[3]
Teegarden's Star b Teegarden's Star Template:StarM ≥1.05 ~1.02 1.15 264 4.91 12.5 Radius is estimated[5][6]
TOI-700 d TOI-700 Template:StarM ~1.72 1.14 0.87 246 37.4 101
Kepler-1649c Kepler-1649 Template:StarM ~1.20 1.06 0.75 237 19.5 301 [7]
TRAPPIST-1d TRAPPIST-1 Template:StarM 0.39 0.78 3.39 1.12 258 4.05 41 Confirmed to be rocky[8][9]
Luyten b Luyten's Star Template:StarM ≥2.89 ~1.35 1.06 258 18.65 12.3 [10]
LP 890-9 c LP 890-9 Template:StarM 1.37 0.91 272 8.46 105 [11]
K2-72e K2-72 Template:StarM ~2.21 1.29 1.30 261 24.2 217 [12]
GJ 1061 d GJ 1061 Template:StarM ≥1.64 ~1.16 0.69 218 13.0 12
GJ 1002 b GJ 1002 Template:StarM ≥1.08 ~1.03 0.67 231 10.3 15.8 [13]
GJ 1061 c GJ 1061 Template:StarM ≥1.74 ~1.18 1.45 275 6.7 12
Kepler-296e Kepler-296 Template:StarK ~2.96 1.52 1.00 276 34.1 737 [1][14]
Wolf 1069 b Wolf 1069 Template:StarM ≥1.26 ~1.08 0.65 250 15.6 31.2 [15]
TRAPPIST-1e TRAPPIST-1 Template:StarM 0.69 0.92 5.65 0.65 230 6.1 41 Confirmed to be rocky[8][9]
Proxima Centauri b Proxima Centauri Template:StarM ≥1.27 ~1.30 0.70 228 11.186 4.25 Affected by solar flare, possibly affected by high radiation[16]
Kepler-442b Kepler-442 Template:StarK ~2.36 1.35 0.70 233 112.3 1193 [1]
Kepler-62f Kepler-62 Template:StarK ~2.8 1.41 0.41 204 267.3 981 [1][17]
TRAPPIST-1f TRAPPIST-1 Template:StarM 1.04 1.04 3.3 ± 0.9 0.37 200 9.2 41 Confirmed to be rocky[8][9]
Teegarden's Star c Teegarden's Star Template:StarM ≥1.11 ~1.04 0.37 199 11.4 12.5 [5]
Kepler-1229b Kepler-1229 Template:StarM ~2.54 1.40 0.32 213 86.8 865 [1]
Kepler-186f Kepler-186 Template:StarM ~1.71 1.17 0.29 188 129.9 579 [1]
TRAPPIST-1g TRAPPIST-1 Template:StarM 1.32 1.13 4.186 0.25 182 12.4 41 Confirmed to be rocky[8][9]
GJ 1002 c GJ 1002 Template:StarM ≥1.36 1.1 0.26 182 21.2 15.8 [13][18]
Kepler-452b Kepler-452 Template:StarG ~5 1.63 1.11 261 384.8 1799 Not confirmed[1][19][20][21][22]
Kepler-62e Kepler-62 Template:StarK ~4.5 1.61 1.15 264 122.4 981 [1][23]
Kepler-1652b Kepler-1652 Template:StarM 1.60 0.84 244 38.1 822
Wolf 1061c Wolf 1061 Template:StarM ≥3.41 ~1.60 1.30 271 17.9 13.8 [1]
Kepler-1410b Kepler-1410 Template:StarK 1.78 1.07 274 60.9 1196
Gliese 667 Cc Gliese 667 C Template:StarM ≥3.81 ~1.54 0.88 277 28.1 23.62 [24][1]
Kepler-1544 b Kepler-1544 Template:StarK 1.78 0.84 248 168.8 1092 [1]
Kepler-283c Kepler-283 Template:StarK 1.82 0.89 248 92.7 1526 [1]
Ross 508 b Ross 508 Template:StarM ≥4.00 1.32 10.8 37 [25]
Kepler-1638b Kepler-1638 Template:StarG 1.87 1.39 276 259.3 4973 [26]
Ross 128 b Ross 128 Template:StarM ≥1.40 ~1.80 1.48 280 9.87 11.0 [27]
Kepler-440b Kepler-440 Template:StarK 1.91 1.44 273 101.1 981 [1]
Gliese 433 d Gliese 433 Template:StarM ≥5.22 1.06 36.1 29.6 [1]
Kepler-1653b Kepler-1653 Template:StarK 2.17 1.04 258 140.3 2461
Kepler-705b Kepler-705 Template:StarM 2.11 0.77 243 56.1 903
K2-332b K2-332 Template:StarM 2.20 1.17 17.7 402 [1]
Kepler-155c Kepler-155 Template:StarM 2.24 1.05 52.7 957 [1]
TOI-2257 b TOI-2257 Template:StarM 2.20 0.74 35.2 188 Highly eccentric[1][28]
Kepler-443b Kepler-443 Template:StarK 2.35 0.89 247 177.7 2615 [1]
Kepler-22b Kepler-22 Template:StarG 2.38 1.10 261 289.9 635 [1][29]
Kepler-1701b Kepler-1701 Template:StarK 2.22 1.42 275 169.1 1904 [1][30]
Kepler-1606b Kepler-1606 Template:StarG 2.07 1.64 277 196.4 2710 [31]
K2-9b K2-9 Template:StarM 2.25 1.45 279 18.4 270 [1][32]
Gliese 180 c Gliese 180 Template:StarM ≥6.40 0.78 239 24.3 39 Not confirmed[1][33]
Gliese 163 c Gliese 163 Template:StarM ≥6.80 1.25 277 25.6 49 [1]
Kepler-1540b Kepler-1540 Template:StarK 2.49 0.78 250 125.4 799
Kepler-174d Kepler-174 Template:StarK 2.19 0.59 206 247.4 1254 [1]
HD 40307 g HD 40307 Template:StarK ≥7.09 0.67 226 197.8 42 Not confirmed[1][34]
Kepler-296f Kepler-296 Template:StarK 1.80 0.44 225 63.3 737 [1][35]
HIP 38594 b HIP 38594 Template:StarM ≥8.10 1.34 60.7 58 [1]
K2-288Bb K2-288 B Template:StarM 1.91 0.44 207 31.4 214
HD 216520 c HD 216520 Template:StarK ≥9.44 1.28 154.4 64 [1]
GJ 3293 d GJ 3293 Template:StarM ≥7.60 0.59 223 48.1 66 [1]
LHS 1140 b LHS 1140 Template:StarM 5.60 1.73 5.9±0.3 0.43 226 24.7 49 Likely ocean world or dense mini-Neptune[36]
Gliese 357 d Gliese 357 Template:StarM ≥6.10 0.38 200 55.7 31
Gliese 229 Ac Gliese 229 A Template:StarM ≥8.57 0.44 216 121.9 18.8
Gliese 514 b Gliese 514 Template:StarM ≥5.20 0.27 202 140.4 25 Highly eccentric[37]
Gliese 180 d Gliese 180 Template:StarM ≥7.56 0.26 106.3 39 [1]
Gliese 625 b Gliese 625 Template:StarM ≥2.82 14.628 21.1 Only in HZ if very optimistic models used[38][39][40]
L 98-59 f L 98-59 Template:StarM ≥2.46 >1 ~280 23.15 34.6 Unconfirmed candidate[41]
Kepler-235e Kepler-235 Template:StarK ~2 ~1.32 ~277 46.18 ~1396 Likely non-rocky, may or may not be in HZ depending on data source[26][42][43]

Previous candidates

Some exoplanet candidates detected by radial velocity that were originally thought to be potentially habitable were later found to most likely be artifacts of stellar activity. These include Gliese 581 d & g,[44][45][46] Gliese 667 Ce & f,[24][47] Gliese 682 b & c,[33] Kapteyn b,[48][49] and Gliese 832 c.[50]

HD 85512 b was initially estimated to be potentially habitable,[51][52] but updated models for the boundaries of the habitable zone placed the planet interior to the HZ,[53][54] and it is now considered non-habitable.[1] Kepler-69c has gone through a similar process; though initially estimated to be potentially habitable,[55] it was quickly realized that the planet is more likely to be similar to Venus,[56] and is thus no longer considered habitable.[1] Several other planets, such as Gliese 180 b, also appear to be examples of planets once considered potentially habitable but later found to be interior to the habitable zone.[1]

Similarly, Tau Ceti e and f were initially both considered potentially habitable,[57] but with improved models of the circumstellar habitable zone, as of 2022 PHL does not consider either planet potentially habitable.[1][failed verification] Kepler-438b was also initially considered potentially habitable; however, it was later found to be a subject of powerful flares that can strip a planet of its atmosphere, so it is now considered non-habitable.[1]

K2-3d and K2-18b were originally considered potentially habitable, and the latter remains listed in the HEC,[1] but recent studies have shown them to be gaseous sub-Neptunes and thus unlikely to be habitable.[58][59][60][61][62][63]

KOI-1686.01 was also considered a potentially habitable exoplanet after its detection in 2011, until proven a false positive by NASA in 2015.[64] Several other KOIs, like Kepler-577b and Kepler-1649b, were considered potentially habitable prior to confirmation, but with new data are no longer considered habitable.

See also

References

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External links