There are 5,653 known exoplanets, or planets outside the Solar System that orbit a star, as of April 1, 2024; only a small fraction of these are located in the vicinity of the Solar System.[3] Within 10 parsecs (32.6 light-years), there are 104 exoplanets listed as confirmed by the NASA Exoplanet Archive.[note 1][4] Among the over 500 known stars and brown dwarfs within 10 parsecs,[5][note 2] around 60 have been confirmed to have planetary systems; 51 stars in this range are visible to the naked eye,[note 3][7] eight of which have planetary systems.
The first report of an exoplanet within this range was in 1998 for a planet orbiting around Gliese 876 (15.3 light-years (ly) away), and the latest as of 2023 are two around Gliese 367 (30.7 ly). The closest exoplanets are those found orbiting the star closest to the Solar System, which is Proxima Centauri 4.25 light-years away. The first confirmed exoplanet discovered in the Proxima Centauri system was Proxima Centauri b, in 2016. HD 219134 (21.6 ly) has six exoplanets, the highest number discovered for any star within this range.
Most known nearby exoplanets orbit close to their stars. A majority are significantly larger than Earth, but a few have similar masses, including planets around YZ Ceti, Gliese 367, and Proxima Centauri which may be less massive than Earth. Several confirmed exoplanets are hypothesized to be potentially habitable, with Proxima Centauri b and GJ 1002 b (15.8 ly) considered among the most likely candidates.[8] The International Astronomical Union has assigned proper names to some known extrasolar bodies, including nearby exoplanets, through the NameExoWorlds project. Planets named in the 2015 event include the planets around Epsilon Eridani (10.5 ly) and Fomalhaut,[note 4][11] while planets named in the 2022 event include those around Gliese 436, Gliese 486, and Gliese 367.[12]
Exoplanets within 10 parsecs
| ° | Mercury, Earth and Jupiter (for comparison purposes) |
| # | Confirmed multiplanetary systems |
| ↑ | Exoplanets believed to be potentially habitable[8] |
| Host star system | Companion exoplanet (in order from star) | Notes and additional planetary observations | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Name | Distance (ly) | Apparent magnitude (V) | Mass (M☉) | Label [note 5] | Mass (ME)[note 6] | Radius (R🜨) | Semi-major axis (AU) | Orbital period (days) | Eccentricity | Inclination (°) | Discovery method | Discovery year | |
| Sun° | 0.000016 | −26.7 | 1 | Mercury | 0.055 | 0.3829 | 0.387 | 88.0 | 0.205 | — | — | — | — |
| Earth | 1 | 1 | 1 | 365.3 | 0.0167 | — | — | — | |||||
| Jupiter | 317.8 | 10.973 | 5.20 | 4,333 | 0.0488 | — | — | — | |||||
| Proxima Centauri# | 4.2465 | 11.13 | 0.123 | d | ≥0.26 | — | 0.0289 | 5.122 | 0.04 | — | RV | 2022 | [14][15] one disputed candidate (c)[16][17][18][19] |
| b↑ | ≥1.07 | — | 0.0486 | 11.19 | 0.02 | — | RV | 2016 | |||||
| Lalande 21185# | 8.304 | 7.52 | 0.46 | b | ≥2.69 | — | 0.0788 | 12.94 | 0.06 | — | RV | 2019 | 1 candidate[20] |
| c | ≥13.6 | — | 2.94 | 2,946 | 0.13 | — | RV | 2021 | |||||
| Epsilon Eridani | 10.489 | 3.73 | 0.781 | Ægir | 242 | — | 3.53 | 2,689 | 0.26 | 166.5 | RV | 2000 | 1 inferred planet, 1 or possibly 2 inner debris discs, and an outer disc[21][22] |
| Lacaille 9352# | 10.724 | 7.34 | 0.489 | b | ≥4.2 | — | 0.068 | 9.262 | 0.03 | — | RV | 2019 | 1 candidate[23][24] |
| c | ≥7.6 | — | 0.120 | 21.79 | 0.03 | — | RV | 2019 | |||||
| Ross 128 | 11.007 | 11.1 | 0.168 | b↑ | ≥1.40 | — | 0.0496 | 9.866 | 0.12 | — | RV | 2017 | [25] |
| Groombridge 34 A# | 11.619 | 8.1 | 0.38 | b | ≥3.03 | — | 0.072 | 11.44 | 0.09 | ~54? | RV | 2014 | [26][27] |
| c | ≥36 | — | 5.4 | 7,600 | 0.27 | ~54? | RV | 2018 | |||||
| Epsilon Indi A | 11.867 | 4.83 | 0.762 | b | 941 | — | 11.08 | 15,700 | 0.42 | 98.7 | RV | 2018 | [28][22] |
| Tau Ceti# | 11.912 | 3.50 | 0.78 | g | ≥1.75 | — | 0.133 | 20.0 | 0.06 | ~35? | RV | 2017 | 4 candidates [29][30][8][31][32][33] |
| h | ≥1.8 | — | 0.243 | 49.4 | 0.23 | ~35? | RV | 2017 | |||||
| e | ≥3.9 | — | 0.538 | 163 | 0.18 | ~35? | RV | 2017 | |||||
| f | ≥3.9 | — | 1.33 | 640 | 0.16 | ~35? | RV | 2017 | |||||
| GJ 1061# | 11.984 | 7.52 | 0.113 | b | ≥1.37 | — | 0.021 | 3.204 | <0.31 | — | RV | 2019 | two solutions for d's orbit[34] |
| c↑ | ≥1.74 | — | 0.035 | 6.689 | <0.29 | — | RV | 2019 | |||||
| d↑ | ≥1.64 | — | 0.054 | 13.03 | <0.53 | — | RV | 2019 | |||||
| YZ Ceti# | 12.122 | 12.1 | 0.130 | b | ≥0.70 | — | 0.0163 | 2.021 | 0.06 | — | RV | 2017 | [35] |
| c | ≥1.14 | — | 0.0216 | 3.060 | 0.0 | — | RV | 2017 | |||||
| d | ≥1.09 | — | 0.0285 | 4.656 | 0.07 | — | RV | 2017 | |||||
| Luyten's Star# | 12.348 | 11.94 | 0.29 | c | ≥1.18 | — | 0.0365 | 4.723 | 0.10 | — | RV | 2017 | [36][23] |
| b↑ | ≥2.89 | — | 0.0911 | 18.65 | 0.17 | — | RV | 2017 | |||||
| d | ≥10.8 | — | 0.712 | 414 | 0.17 | — | RV | 2019 | |||||
| e | ≥9.3 | — | 0.849 | 542 | 0.03 | — | RV | 2019 | |||||
| Teegarden's Star# | 12.497 | 15.40 | 0.08 | b↑ | ≥1.05 | — | 0.0252 | 4.910 | 0 | — | RV | 2019 | [37] |
| c↑ | ≥1.11 | — | 0.0443 | 11.41 | 0 | — | RV | 2019 | |||||
| Wolf 1061# | 14.050 | 10.1 | 0.25 | b | ≥1.91 | — | 0.0375 | 4.887 | 0.15 | — | RV | 2015 | [36] |
| c↑ | ≥3.41 | — | 0.0890 | 17.87 | 0.11 | — | RV | 2015 | |||||
| d | ≥7.7 | — | 0.470 | 217 | 0.55 | — | RV | 2015 | |||||
| TZ Arietis | 14.578 | 12.30 | 0.14 | b | ≥67 | — | 0.88 | 771 | 0.46 | — | RV | 2019 | 2 refuted candidates[23][38][39] |
| Gliese 687# | 14.839 | 9.15 | 0.41 | b | ≥17.2 | — | 0.163 | 38.14 | 0.17 | — | RV | 2014 | [23][38] |
| c | ≥16.0 | — | 1.165 | 728 | 0.40 | — | RV | 2019 | |||||
| Gliese 674 | 14.849 | 9.38 | 0.35 | b | ≥11.1 | — | 0.039 | 4.694 | 0.20 | — | RV | 2007 | [40] |
| Gliese 876# | 15.238 | 10.2 | 0.33 | d | 6.68 | — | 0.0210 | 1.938 | 0.04 | 56.7 | RV | 2005 | [41] |
| c | 235 | — | 0.1309 | 30.10 | 0.26 | 56.7 | RV | 2000 | |||||
| b | 749 | — | 0.2098 | 61.10 | 0.03 | 56.7 | RV | 1998 | |||||
| e | 16 | — | 0.3355 | 123.6 | 0.05 | 56.7 | RV | 2010 | |||||
| GJ 1002# | 15.806 | 13.84 | 0.12 | b↑ | ≥1.08 | — | 0.0457 | 10.35 | — | — | RV | 2022 | [42] |
| c↑ | ≥1.36 | — | 0.0738 | 21.2 | — | — | RV | 2022 | |||||
| Gliese 832 | 16.200 | 8.67 | 0.45 | b | 315 | — | 3.7 | 3,853 | 0.05 | 51 or 134 | RV | 2008 | 1 refuted candidate[43][44] |
| GJ 3323# | 17.531 | 12.2 | 0.164 | b | ≥2.0 | — | 0.0328 | 5.36 | 0.2 | — | RV | 2017 | [45] |
| c | ≥2.3 | — | 0.126 | 40.5 | 0.2 | — | RV | 2017 | |||||
| Gliese 251 | 18.215 | 9.65 | 0.372 | b | ≥4.0 | — | 0.0818 | 14.2 | 0.10 | — | RV | 2020 | [46] |
| Gliese 229 A# | 18.791 | 8.14 | 0.58 | c↑ | ≥7.3 | — | 0.339 | 122 | 0.19 | — | RV | 2020 | Ab not confirmed until 2020.[47] |
| b | ≥8.5 | — | 0.898 | 526 | 0.10 | — | RV | 2014 | |||||
| Gliese 752 A | 19.292 | 9.13 | 0.46 | b | ≥13.6 | — | 0.338 | 106 | 0.03 | — | RV | 2018 | [48][23] |
| 82 G. Eridani# | 19.704 | 4.26 | 0.85 | b | ≥2.7 | — | 0.121 | 18.3 | ~0 | — | RV | 2011 | 2 candidates [49][50][51] |
| c | ≥2.4 | — | 0.204 | 40.1 | ~0 | — | RV | 2011 | |||||
| d | ≥4.8 | — | 0.350 | 90 | ~0 | — | RV | 2011 | |||||
| e | ≥4.8 | — | 0.509 | 147 | 0.29 | — | RV | 2017 | |||||
| EQ Pegasi A | 20.400 | 10.38 | 0.436 | b | 718 | — | 0.643 | 284 | 0.35 | 69.2 | Astrometry | 2022 | [52] |
| Gliese 581# | 20.549 | 10.5 | 0.31 | e | ≥1.7 | — | 0.0282 | 3.15 | 0.0 | ~45? | RV | 2009 | 3 refuted candidates and a disc [53][54][55][56] |
| b | ≥16 | — | 0.0406 | 5.37 | 0.0 | ~45? | RV | 2005 | |||||
| c | ≥5.5 | — | 0.072 | 12.9 | 0.0 | ~45? | RV | 2007 | |||||
| Gliese 338 B | 20.658 | 7.0 | 0.64 | b | ≥10.3 | — | 0.141 | 24.5 | 0.11 | — | RV | 2020 | [57] |
| Gliese 625 | 21.131 | 10.2 | 0.30 | b | ≥2.8 | — | 0.0784 | 14.6 | ~0.1 | — | RV | 2017 | [58] |
| HD 219134# | 21.336 | 5.57 | 0.78 | b | 4.7 | 1.60 | 0.0388 | 3.09 | ~0 | 85.05 | RV | 2015 | [59][60][61] |
| c | 4.4 | 1.51 | 0.065 | 6.77 | 0.062 | 87.28 | RV | 2015 | |||||
| d | ≥16 | — | 0.237 | 46.9 | 0.138 | ~87? | RV | 2015 | |||||
| f | ≥7.3 | — | 0.146 | 22.7 | 0.148 | ~87? | RV | 2015 | |||||
| g | ≥11 | — | 0.375 | 94.2 | 0 | ~87? | RV | 2015 | |||||
| h (e) | ≥108 | — | 3.11 | 2,247 | 0.06 | ~87? | RV | 2015 | |||||
| LTT 1445 A# | 22.387 | 10.53 | 0.26 | c | 1.54 | 1.15 | 0.0266 | 3.12 | <0.22 | 87.43 | Transit | 2021 | [62][63] |
| b | 2.87 | 1.30 | 0.0381 | 5.36 | <0.11 | 89.68 | Transit | 2019 | |||||
| Gliese 393 | 22.953 | 8.65 | 0.41 | b | ≥1.71 | — | 0.0540 | 7.03 | 0.00 | — | RV | 2019 | [23][64] |
| Gliese 667 C# | 23.623 | 10.2 | 0.33 | b | ≥5.4 | — | 0.049 | 7.20 | 0.13 | ~52? | RV | 2009 | 5 dubious candidates [65][8][66][67][23] |
| c↑ | ≥3.9 | — | 0.1251 | 28.2 | 0.03 | ~52? | RV | 2011 | |||||
| Gliese 514 | 24.878 | 9.03 | 0.53 | b | ≥5.2 | — | 0.421 | 140 | 0.45 | — | RV | 2022 | [68] |
| Gliese 486 | 26.351 | 11.395 | 0.32 | Su | 2.8 | 1.31 | 0.0173 | 1.47 | <0.05 | 88.4 | Transit | 2021 | [69] |
| Gliese 686 | 26.613 | 9.58 | 0.42 | b | ≥7.1 | — | 0.097 | 15.5 | 0.04 | — | RV | 2019 | [70][23] |
| 61 Virginis# | 27.836 | 4.74 | 0.95 | b | ≥5.1 | — | 0.0502 | 4.22 | ~0.1 | ~77? | RV | 2009 | a debris disc,[71] 1 disputed candidate[72] |
| c | ≥18 | — | 0.218 | 38.0 | 0.14 | ~77? | RV | 2009 | |||||
| CD Ceti | 28.052 | 14.001 | 0.161 | b | ≥3.95 | — | 0.0185 | 2.29 | 0 | — | RV | 2020 | [73] |
| Gliese 785# | 28.739 | 6.13 | 0.78 | b | ≥17 | — | 0.32 | 75 | 0.13 | — | RV | 2010 | [74] |
| c | ≥24 | — | 1.18 | 530 | ~0.3 | — | RV | 2011 | |||||
| Gliese 849# | 28.750 | 10.4 | 0.49 | b | ≥270 | — | 2.26 | 1,910 | 0.05 | — | RV | 2006 | [75][23] |
| c | ≥300 | — | 4.82 | 5,520 | 0.087 | — | RV | 2006 | |||||
| Gliese 433# | 29.605 | 9.79 | 0.48 | b | ≥6.0 | — | 0.062 | 7.37 | 0.04 | — | RV | 2009 | [76][23][47] |
| d | ≥5.2 | — | 0.178 | 36.1 | 0.07 | — | RV | 2020 | |||||
| c | ≥32 | — | 4.82 | 5,090 | 0.12 | — | RV | 2012 | |||||
| HD 102365 A | 30.396 | 4.89 | 0.85 | b | ≥16 | — | 0.46 | 122 | 0.34 | — | RV | 2010 | [77] |
| Gliese 367 | 30.719 | 9.98 | 0.45 | Tahay | 0.55 | 0.72 | 0.0071 | 0.32 | 0 | 80.75 | Transit | 2021 | [78] |
| Gliese 357# | 30.776 | 10.9 | 0.34 | b | 6.1 | 1.17 | 0.035 | 3.93 | 0.02 | 88.92 | Transit | 2019 | [79][23] |
| c | ≥3.6 | — | 0.061 | 9.13 | 0.04 | ~89? | RV | 2019 | |||||
| d↑ | ≥7.7 | — | 0.204 | 55.7 | 0.03 | ~89? | RV | 2019 | |||||
| Gliese 176 | 30.937 | 10.1 | 0.45 | b | ≥8.0 | — | 0.066 | 8.77 | 0.08 | — | RV | 2007 | 1 disputed candidate[80][81][23] |
| GJ 3512# | 30.976 | 13.11 | 0.123 | b | ≥147 | — | 0.338 | 204 | 0.44 | — | RV | 2019 | [82] |
| c | ≥54 | — | >1.2 | >1390 | — | — | RV | 2019 | |||||
| Wolf 1069 | 31.229 | 13.99 | 0.167 | b↑ | ≥1.26 | — | 0.0672 | 15.6 | — | — | RV | 2023 | [83] |
| AU Microscopii# | 31.683 | 8.63 | 0.50 | b | 17 | 4.38 | 0.0645 | 8.463 | 0.10 | 89.03 | Transit | 2020 | [84][85] |
| c | <28 | 3.51 | 0.1101 | 18.86 | 0 | 88.62 | Transit | 2020 | |||||
| Gliese 436 | 31.882 | 10.67 | 0.41 | Awohali | 21.4 | 4.33 | 0.0280 | 2.64 | 0.15 | 85.8 | RV | 2004 | [86][87] |
| Gliese 49 | 32.158 | 8.9 | 0.57 | b | ≥16.4 | — | 0.106 | 17.3 | 0.03 | — | RV | 2019 | [88] |
| HD 260655# | 32.608 | 9.77 | 0.439 | b | 2.14 | 1.240 | 0.0293 | 2.780 | 0.039 | 87.35 | Transit | 2022 | [89] |
| c | 3.09 | 1.533 | 0.0475 | 5.706 | 0.038 | 87.79 | Transit | 2022 | |||||
Excluded objects
Unlike for bodies within the Solar System, there is no clearly established method for officially recognizing an exoplanet. According to the International Astronomical Union, an exoplanet should be considered confirmed if it has not been disputed for five years after its discovery.[90] There have been examples where the existence of exoplanets has been proposed, but even after follow-up studies their existence is still considered doubtful by some astronomers. Such cases include Wolf 359 (7.9 ly, in 2019),[23] LHS 288 (15.8 ly, in 2007),[91]Gliese 682 (16.3 ly, in 2014),[47]40 Eridani A (16.3 ly, in 2018),[92][72]and GJ 1151 (26.2 ly, in 2021).[93][94][95]There are also several instances where proposed exoplanets were later disproved by subsequent studies, including candidates around Toliman (4.36 ly),[96]Barnard's Star (5.96 ly),[97][98]Kapteyn's Star (12.8 ly),[99]Van Maanen 2 (14.1 ly),[100]Groombridge 1618 (15.9 ly),[101]AD Leonis (16.2 ly),[102]VB 10 (19.3 ly),[103] and Fomalhaut (25.1 ly).[2]
In 2021, a candidate planet was detected around Vega, though it has yet to be confirmed.[104] Another candidate planet, Candidate 1, was directly imaged around Rigil Kentaurus, though it may also be a clump of asteroids or an artifact of the discovery mechanism.[105]
The Working Group on Extrasolar Planets of the International Astronomical Union adopted in 2003 a working definition on the upper limit for what constitutes a planet: not being massive enough to sustain thermonuclear fusion of deuterium. Some studies have calculated this to be somewhere around 13 times the mass of Jupiter, and therefore objects more massive than this are usually classified as brown dwarfs.[106] Some proposed candidate exoplanets have been shown to be massive enough to fall above the threshold, and thus are likely brown dwarfs, as is the case for: SCR 1845-6357 B (13.1 ly),[107] SDSS J1416+1348 B (30.3 ly),[108] and WISE 1217+1626 B (30 ly).[109]
Excluded from the current list are known examples of potential free-floating sub-brown dwarfs, or "rogue planets", which are bodies that are too small to undergo fusion yet they do not revolve around a star. Known such examples include: WISE 0855−0714 (7.4 ly),[110] UGPS 0722-05, (13.4 ly)[111] WISE 1541−2250 (18.6 ly),[112] and SIMP J01365663+0933473 (20.0 ly).[113]
See also
Notes
References
External links
- "Extrasolar Planets". The Planetary Society. Planetary.org.
- "Extrasolar Planets News". Science Daily.
- "Exoplanet Exploration: Planets Beyond our Solar System". Exoplanet Exploration Program and Jet Propulsion Laboratory. NASA. 2015-12-16.
- "Universe - Exoplanets (pictures, video, facts & news)". BBC. Archived from the original on 2018-02-13. Retrieved 2018-03-23.
- "PHL's Exoplanets Catalog". Planetary Habitability Laboratory. UPR Arecibo. 2018-03-02.
- Onsi Fakhouri. "Exoplanet Orbit Database". Exoplanet Data Explorer. Exoplanets.org.
- "NASA Exoplanet Archive". Caltech.
- "Stars Within 20 Light Years". Atlas of the Universe.
