Jump to content

List of nearest terrestrial exoplanet candidates

From Wikipedia, the free encyclopedia

This list of nearest terrestrial exoplanet candidates contains possible terrestrial ("rocky") exoplanets spaced at a distance of up to 50 light-years from the Solar System, ordered by increasing distance.[1][2][3]

They may be composed primarily of silicate rocks and/or metals. Within the Solar System, the terrestrial planets are the inner planets closest to the Sun.

Exoplanets discovered (incomplete)

[edit]

This list is incomplete, currently containing 34 exoplanets, 11 of which probably lie inside their star's habitable zone.

There are roughly 2,000 stars at a distance of up to 50 light-years from the Solar System[4] (64 of them are yellow-orange "G" stars like the Sun[5]). As many as 15% of them could have Earth-sized planets in the habitable zones.[6]

On November 4, 2013, astronomers reported, based on Kepler space mission data, that there could be as many as 40 billion Earth-sized planets orbiting in the habitable zones of Sun-like stars and red dwarf stars within the Milky Way galaxy.[7][8] Eleven billion of these estimated planets may be orbiting Sun-like stars.[9] The nearest such planet was then as close as 12 light-years away[7][8] but (see below) is now estimated slightly above four light-years away.

On August 24, 2016, astronomers announced the discovery of a rocky planet in the habitable zone of Proxima Centauri, the closest star to Earth (not counting the Sun). Called Proxima b, the planet is 1.3 times the mass of Earth and has an orbital period of roughly 11.2 Earth days.[10] However, Proxima Centauri's classification as a red dwarf casts doubts on the habitability of any exoplanets in its orbit due to low stellar flux, high probability of tidal locking, small circumstellar habitable zones and high stellar variation. Another likely candidate is Alpha Centauri, Earth's nearest Sun-like star system 4.37 light-years away. Estimates place the probability of finding a habitable planet around Alpha Centauri A or B at roughly 75%.[11] Alpha Centauri is the target of several exoplanet-finding missions, including Breakthrough Starshot and Mission Centaur, the latter of which is chronicled in the 2016 documentary film The Search for Earth Proxima.[12]

In 2023, astronomers used the radial velocity method to confirm that the exoplanet Wolf 1069 b sits in the habitable zone of Wolf 1069. Located 31 light years from Earth, this planet is 1.26 times the mass of Earth and has a radius of 1.08 times the Earth's. Though Wolf 1069 b is likely tidally locked, its daylight side may still be habitable. It has similar characteristics to Proxima Centauri b and is one of the nearest discovered potentially habitable exoplanets to Earth. Wolf 1069 b is likely rocky, with an Earth-like composition, and climate models suggest that it is habitable for a broad range of possible atmospheres although the nature of its true atmosphere is unknown. Characterizing its atmosphere is more difficult than with a transiting exoplanet as transmission spectroscopy is inapplicable, and instruments for alternative techniques such as analysis of thermal emission and reflected light are not yet available. The angular separation between Wolf 1069 b and its star is also small, which further complicates these measurements.[13][14][15]

Data Table

[edit]
Name M🜨 R🜨 g Ts a e [s] D
Mass (in Earth masses)
Radius (in Earth radii)
Surface gravity (1 – standard Earth gravity)
Surface temperature
Semi-major axis in astronomical units
Orbital eccentricity
Main source
Distance from the Sun in lightyears
Proxima Centauri b ≥1.27 ~1.1 234 K
-39°C		 0.05 <0.35 [10] 4.22
Proxima Centauri c ~7 39 K
-234 °C[16]		 ~1.489 ~0.04 4.22
Ross 128 b ≥1.40 213 to 301 K
-60 to 28 °C		 11.03
Luyten b ≥2.89 ≥1.35 259 K
-14 °C		 0.091 0.10 12.20
Wolf 1061c ≥4.3 ≥1.64 -
-		 [17] 13.8
Wolf 1061d ≥5.21 ≥2.04 -
-		 13.8
Wolf 1069 b 1.26 1.08 250.1 K
-23.1 °C 		0.0672 [13] 31
Gliese 876 d[18] 6.8 650 K
377 °C[19]		 0.021 0.21 [20] 15
Gliese 682 b ≥2 -
-		 [6]
[21]
[17]		 16
Gliese 832 c ≥5.4 251 K
-22 °C 		0.162 0.03 [22][23] 16.16
82 G. Eridani b ≥2.7 660 K
387 °C[1]		 0.1207 0 [2] 19.71
82 G. Eridani c ≥2.4 508 K
235 °C[1]		 0.2036 0 [2] 19.71
82 G. Eridani d ≥4.8 388 K
115 °C[1] 		0.3499 0 [2] 19.71
Gliese 581 e ≥1.7 -
-		 0.029 0 [24] 20
Gliese 581 c[25] ≥5.6 -
-		 0.072 0 [24] 20
Gliese 581 d[26] ≥5.6 2.34[27] 1.27[27] 233 K
-41 °C[27] 		0.218 0 [24] 20
HD 219134 b 4.5 1.6 700 K
427 °C 		[28] 21
Gliese 667 Cb 6.30 1.44 445 K

172 °C

0.05 0.09 [27] 22
Gliese 667 Cc[29][30] 3.8 1.32 302 K
29 °C 		0.13 0.34 [27] 22
61 Virginis b[31] ≥5.1 -
-		 0.050 0.12 [32] 28
HD 85512 b[33] ≥3.6 1.74[27] 1.33[27] 351 K
78 °C[27] 		0.26 0.11 [34] 36
GJ 180 b ≥2.3 312 K
39 °C 		[6][22] 38
TRAPPIST-1b -
-		 [35] 39.5
TRAPPIST-1c -
-		 [35] 39.5
TRAPPIST-1d 0.48 282.1 K
9 °C[27]		 [35] 39.5
TRAPPIST-1e 246.1 K
-27.1 °C[27]		 [35] 39.5
TRAPPIST-1f 219 K
-54 °C[27]		 [35] 39.5
TRAPPIST-1g 198.6 K
-75 °C[27]		 [35] 39.5
TRAPPIST-1h 169 K
-104 °C[27]		 [35] 39.5
55 Cancri e
(Janssen)		 8.6 -
-		 0.016 0.17 [36] 40
HD 40307 b[37] ≥4.2 -
-		 0.047 0.2 [37] 42
HD 40307 c[37] ≥6.8 -
-		 0.081 0.06 [37] 42
HD 40307 d[38] ≥9.2 -
-		 0.134 0.07 [37] 42
HD 40307 e ≥3.5 -
-		 0.1886 0.15 [3] 42
HD 40307 f ≥5.2 385 K
112 °C 		0.247 0.02 [3] 42
HD 40307 g ≥7.1 284 K
11 °C[39] 		0.600 0.29 [3] 42

Note: There is no scientific consensus about terrestrial composition of most of the planets in the list. Sources in the "Main source" column confirm the possibility of terrestrial composition.

In September 2012, the discovery of two planets orbiting Gliese 163[40] was announced.[41][42] One of the planets, Gliese 163 c, about 6.9 times the mass of Earth and somewhat hotter, was considered to be within the habitable zone, but is probably not terrestrial.[41][42]

In May 2016, the finding of three Earth-like planets of ultracool dwarf TRAPPIST-1 has been released.

The existence of the planet Gliese 832 c was refuted in 2022, when a study found that the radial velocity signal shows characteristics of a signal originating from stellar activity, and not from a planet.

Statistics

[edit]
Distance from the Solar System
Distance Lying within
the habitable zone 		All
< 10 light-years 0 (2?) 2
< 20 light-years 6 15
< 30 light-years 8 22
< 40 light-years 10 24
< 50 light-years 11 31

Note: in most cases the composition of the atmosphere and atmosphere pressure of exoplanets are unknown, so surface temperatures are estimates based on computer models and expert opinions.

See also

[edit]

References

[edit]
  1. ^ a b c d Pepe, F.; et al. (2011), "The HARPS search for Earth-like planets in the habitable zone: I – Very low-mass planets around HD20794, HD85512 and HD192310", Astronomy & Astrophysics, 534: A58, arXiv:1108.3447, Bibcode:2011A&A...534A..58P, doi:10.1051/0004-6361/201117055, S2CID 15088852
  2. ^ a b c d Schneider, Jean, "Star: HD 20794", Extrasolar Planets Encyclopaedia, archived from the original on October 8, 2011, retrieved 2011-12-05
  3. ^ a b c d Tuomi, Mikko; Anglada-Escudé, Guillem; Gerlach, Enrico; Jones, Hugh R. A.; Reiners, Ansgar; Rivera, Eugenio J.; Vogt, Steven S.; Butler, R. Paul (17 December 2012). "Habitable-zone super-Earth candidate in a six-planet system around the K2.5V star HD 40307". Astronomy & Astrophysics. 549: A48. arXiv:1211.1617. Bibcode:2013A&A...549A..48T. doi:10.1051/0004-6361/201220268. S2CID 7424216.
  4. ^ "Stars within 50 light years". Retrieved 3 October 2015.
  5. ^ "G stars within 100 light-years". Retrieved 3 October 2015.
  6. ^ a b c Tuomi, Mikko; Jones, Hugh R. A.; Barnes, John R.; Anglada-Escudé, Guillem; Jenkins, James S. (2014). "Bayesian search for low-mass planets around nearby M dwarfs. Estimates for occurrence rate based on global detectability statistics". Monthly Notices of the Royal Astronomical Society. 441 (2): 1545–1569. arXiv:1403.0430. Bibcode:2014MNRAS.441.1545T. doi:10.1093/mnras/stu358.
  7. ^ a b Overbye, Dennis (November 4, 2013). "Far-Off Planets Like the Earth Dot the Galaxy". New York Times. Retrieved November 5, 2013.
  8. ^ a b Petigura, Eric A.; Howard, Andrew W.; Marcy, Geoffrey W. (October 31, 2013). "Prevalence of Earth-size planets orbiting Sun-like stars". Proceedings of the National Academy of Sciences of the United States of America. 110 (48): 19273–19278. arXiv:1311.6806. Bibcode:2013PNAS..11019273P. doi:10.1073/pnas.1319909110. PMC 3845182. PMID 24191033.
  9. ^ Khan, Amina (November 4, 2013). "Milky Way may host billions of Earth-size planets". Los Angeles Times. Retrieved November 5, 2013.
  10. ^ a b Anglada-Escudé, Guillem; Amado, Pedro J.; Barnes, John; et al. (2016). "A terrestrial planet candidate in a temperate orbit around Proxima Centauri" (PDF). Nature. 536 (7617): 437–440. arXiv:1609.03449. Bibcode:2016Natur.536..437A. doi:10.1038/nature19106. PMID 27558064. S2CID 4451513.
  11. ^ Billings, Lee. "Miniature Space Telescope Could Boost the Hunt for "Earth Proxima"". Scientific American.
  12. ^ "The Search for Earth Proxima". The Atlantic.
  13. ^ a b Kossakowski, Diana; Kürster, Martin; Trifonov, Trifon; Henning, Thomas; Kemmer, Jonas; et al. (2023-02-10). "The CARMENES search for exoplanets around M dwarfs - Wolf 1069 b: Earth-mass planet in the habitable zone of a nearby, very low-mass star". Astronomy & Astrophysics. 670 (February 2023). A84. arXiv:2301.02477v2. doi:10.1051/0004-6361/202245322.
  14. ^ Tognetti, Laurence (2023-02-03). "Astronomers discover potential habitable exoplanet only 31 light-years from Earth". Space.com.
  15. ^ Nielbock, Marcus (2023-02-03). "A nearby potentially habitable Earth-mass exoplanet". Max Planck Institute for Astronomy. Retrieved 2024-10-07.
  16. ^ Wall, Mike (12 April 2019). "Possible 2nd Planet Spotted Around Proxima Centauri". Space.com. Retrieved 22 July 2020.
  17. ^ a b "HEC: Data of Potentially Habitable Worlds - Planetary Habitability Laboratory @ UPR Arecibo". Archived from the original on 2012-06-01. Retrieved 2013-01-26.
  18. ^ Fogg, M. J.; Nelson, R. P. (2005). "Oligarchic and giant impact growth of terrestrial planets in the presence of gas giant planet migration". Astronomy and Astrophysics. 441 (2): 791–806. arXiv:astro-ph/0507180. Bibcode:2005A&A...441..791F. doi:10.1051/0004-6361:20053453. S2CID 15248175.
  19. ^ Rivera, E.; et al. (2005). "A ~7.5 M🜨 Planet Orbiting the Nearby Star, GJ 876". The Astrophysical Journal. 634 (1): 625–640. arXiv:astro-ph/0510508. Bibcode:2005ApJ...634..625R. doi:10.1086/491669. S2CID 14122053.
  20. ^ Eugenio J. Rivera, Gregory Laughlin, R. Paul Butler, Steven S. Vogt, Nader Haghighipour, Stefano Meschiari (2010). "The Lick-Carnegie Exoplanet Survey: A Uranus-mass Fourth Planet for GJ 876 in an Extrasolar Laplace Configuration".
  21. ^ http://www.hpcf.upr.edu/~abel/phl/tuomi/hec_orbit_GJ_682_b.png [bare URL image file]
  22. ^ a b "HEC: Data of Potentially Habitable Worlds - Planetary Habitability Laboratory @ UPR Arecibo". Archived from the original on 1 June 2012. Retrieved 3 October 2015.
  23. ^ "A Nearby Super-Earth with the Right Temperature but Extreme Seasons - Planetary Habitability Laboratory @ UPR Arecibo". Archived from the original on 13 May 2019. Retrieved 3 October 2015.
  24. ^ a b c Vogt, S. S. (2010). "The Lick-Carnegie Exoplanet Survey: A 3.1 M_Earth Planet in the Habitable Zone of the Nearby M3V Star Gliese 581". The Astrophysical Journal. 723 (1): 954–965. arXiv:1009.5733. Bibcode:2010ApJ...723..954V. doi:10.1088/0004-637x/723/1/954. S2CID 3163906.
  25. ^ Valencia; Sasselov, Dimitar D.; O'Connell, Richard J. (2007). "Radius and Structure Models of the First Super-Earth Planet". The Astrophysical Journal. 656 (1): 545–551. arXiv:astro-ph/0610122. Bibcode:2007ApJ...656..545V. doi:10.1086/509800. S2CID 17656317.
  26. ^ von Bloh, W.; Bounama, C.; Cuntz, M.; Franck, S. (2007). "The Habitability of Super-Earths in Gliese 581". Astronomy & Astrophysics. 476 (3): 1365–1371. arXiv:0705.3758. Bibcode:2007A&A...476.1365V. doi:10.1051/0004-6361:20077939. S2CID 14475537.
  27. ^ a b c d e f g h i j k l m The Habitable Exoplanets Catalog. The values are just the best estimates and are subject to change.
  28. ^ "Astronomers find star with three super-Earths".
  29. ^ Bonfils, Xavier; Delfosse, Xavier; Udry, Stéphane; Forveille, Thierry; Mayor, Michel; Perrier, Christian; Bouchy, François; Gillon, Michaël; Lovis, Christophe; Pepe, Francesco; Queloz, Didier; Santos, Nuno C.; Ségransan, Damien; Bertaux, Jean-Loup (2011). "The HARPS search for southern extra-solar planets XXXI. The M-dwarf sample". Astronomy and Astrophysics. 549: A109. arXiv:1111.5019. Bibcode:2013A&A...549A.109B. doi:10.1051/0004-6361/201014704. S2CID 119288366.
  30. ^ "A Potential Habitable Exoplanet in a Nearby Triple Star System - Planetary Habitability Laboratory @ UPR Arecibo". Archived from the original on 25 February 2021. Retrieved 3 October 2015.
  31. ^ Vogt, Steven; Wittenmyer; Paul Butler; Simon O'Toole; Henry; Rivera; Stefano Meschiari; Gregory Laughlin; Tinney (2010). "A Super-Earth and two Neptunes Orbiting the Nearby Sun-like star 61 Virginis". The Astrophysical Journal. 708 (2): 1366–1375. arXiv:0912.2599. Bibcode:2010ApJ...708.1366V. doi:10.1088/0004-637X/708/2/1366. S2CID 1979253.
  32. ^ Vogt, Steven (2009). \"A Super-Earth and two Neptunes Orbiting the Nearby Sun-like star 61 Virginis
  33. ^ Kaltenegger, L; Udry, S; Pepe, F (2011). "A Habitable Planet around HD 85512?". 1108: 3561. arXiv:1108.3561. Bibcode:2011arXiv1108.3561K. {{cite journal}}: Cite journal requires |journal= (help)
  34. ^ Kaltenegger, L.; Udry, S.; Pepe, F. (2011). A Habitable Planet around HD 85512?
  35. ^ a b c d e f g Gillon, M; Triaud, AH; Demory, BO; Jehin, E; Agol, E; Deck, KM; Lederer, SM; de Wit, J; Burdanov, A; Ingalls, JG; Bolmont, E; Leconte, J; Raymond, SN; Selsis, F; Turbet, M; Barkaoui, K; Burgasser, A; Burleigh, MR; Carey, SJ; Chaushev, A; Copperwheat, CM; Delrez, L; Fernandes, CS; Holdsworth, DL; Kotze, EJ; Van Grootel, V; Almleaky, Y; Benkhaldoun, Z; Magain, P; Queloz, D (2017). "Seven temperate terrestrial planets around the nearby ultracool dwarf star TRAPPIST-1" (PDF). Nature. 542 (7642): 456–460. arXiv:1703.01424. Bibcode:2017Natur.542..456G. doi:10.1038/nature21360. PMC 5330437. PMID 28230125.
  36. ^ Rebekah; et al. (2010). "Radial velocity planets de-aliased. A new, short period for Super-Earth 55 Cnc e". The Astrophysical Journal. 722 (1): 937–953. arXiv:1005.4050. Bibcode:2010ApJ...722..937D. doi:10.1088/0004-637x/722/1/937. S2CID 118592734.
  37. ^ a b c d e M. Mayor; S. Udry; C. Lovis; F. Pepe; D. Queloz; W. Benz; J.-L. Bertaux; F. Bouchy; C. Mordasini; D. Segransan (2009). "The HARPS search for southern extra-solar planets. XIII. A planetary system with 3 Super-Earths (4.2, 6.9, & 9.2 Earth masses)". Astronomy and Astrophysics. 493 (2): 639–644. arXiv:0806.4587. Bibcode:2009A&A...493..639M. doi:10.1051/0004-6361:200810451. S2CID 116365802.
  38. ^ Barnes, R., Jackson, B., Raymond, S., West, A., Greenberg, R. (2009). "The HD 40307 Planetary System: Super-Earths or Mini-Neptunes?". The Astrophysical Journal. 695 (2): 1006–1011. arXiv:0901.1698. Bibcode:2009ApJ...695.1006B. doi:10.1088/0004-637X/695/2/1006. S2CID 18849636.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  39. ^ "HEC: Data of Potential Habitable Worlds". University of Puerto Rico at Arecibo (Planetary Habitability Laboratory). November 12, 2012. Archived from the original on June 1, 2012. Retrieved January 26, 2013.
  40. ^ Staff (September 20, 2012). "LHS 188 -- High proper-motion Star". Centre de données astronomiques de Strasbourg(Strasbourg astronomical Data Center). Retrieved September 20, 2012.
  41. ^ a b Méndez, Abel (August 29, 2012). "A Hot Potential Habitable Exoplanet around Gliese 163". University of Puerto Rico at Arecibo (Planetary Habitability Laboratory). Archived from the original on October 21, 2019. Retrieved September 20, 2012.
  42. ^ a b Redd, Nola Taylor (September 20, 2012). "Newfound Alien Planet a Top Contender to Host Life". Space.com. Retrieved September 20, 2012.
[edit]
Retrieved from "https://en.wikipedia.org/w/index.php?title=List_of_nearest_terrestrial_exoplanet_candidates&oldid=1262952808"