List of exoplanet extremes

The following are lists of extremes among the known exoplanets. The properties listed here are those for which values are known reliably.

Extremes from Earth's viewpoint
Title Planet Star Data Notes
Most distant discovered SWEEPS-11 / SWEEPS-04 SWEEPS J175902.67−291153.5 27,710 light years.[1] An analysis of the lightcurve of the microlensing event PA-99-N2 suggests the presence of a planet orbiting a star in the Andromeda Galaxy (2.54 ± 0.11 Mly).[2] In late January 2018,[3] a team of scientists led by Xinyu Dai claimed to have discovered a collection of about 2,000 rogue planets in the quasar microlens RX J1131-1231, which is 3.8 billion light-years distant. The bodies range in mass from that of the Moon to several Jupiter masses.[4][3]

The most distant potentially habitable planet confirmed is Kepler-1606b, at 2870 light-years distant,[5] although the unconfirmed planet KOI-5889.01 is over 5,000 light-years distant.

Least distant Proxima Centauri b and c Proxima Centauri 4.22 light years Proxima Centauri b is the closest rocky exoplanet and closest potentially habitable exoplanet known, and c is the closest super-Earth and potentially-ringed planet. As Proxima Centauri is the closest star to the Sun (and will stay so for the next 25,000 years), this is an absolute record.
Most distant directly visible CVSO 30 c CVSO 30 1,200 light years Also first directly imaged planet in system with a transiting planet.
Least distant directly visible Proxima Centauri c Proxima Centauri 4.22 light years Confirmed in 2020 using archival Hubble data from 1995+.
Star with the brightest apparent magnitude with a planet Pollux b Pollux[6] Apparent magnitude is 1.14 The evidence of planets around Vega with an apparent magnitude of 0.03 is strongly suggested by circumstellar disks surrounding it. As of 2018, no planets had yet been confirmed.[7]
Largest angular distance separation from its host star GU Piscium b GU Piscium 42 arc seconds[8] The upper mass limit (13 Jupiter masses) may make this a brown dwarf. WD 0806-661 b has an angular separation of 130.2 arc seconds from WD 0806-661. However, its planetary origin is also unknown. Not counting either of these, DT Virginis b would be the widest-separated definite exoplanet.

Planetary characteristics
Title Planet Star Data Notes
Least massive WD 1145+017 b WD 1145+017 0.00067 M⨁[9]
Most massive The candidate for the most massive planet is contentious, as it is difficult to distinguish between a highly massive planet and a brown dwarf. It is estimated the largest planets are approximately a dozen Jupiter masses.
Largest radius HD 100546 b HD 100546 6.9+2.7
−2.9[10] Jupiter radii		 Largest exoplanet in the NASA Exoplanet Archive, although because of flux from the planet and the disk that are superimposed, the exact size of this planet cannot be determined and the emitting area has this size, composed of the planet and including its disk, not to be mistaken as a single planet radius. Over time, it will shrink to the size of Jupiter. 20 MJ; is likely a brown dwarf.
Smallest radius SDSS J1228+1040 b SDSS J1228+1040 128.6856km (diameter)[11]
Most dense Kepler-131 c Kepler-131 77.7+55
−55 g/cm3[12]		 Highly uncertain
Least dense Kepler-51c, b and/or possibly d[13] Kepler-51[13] ~ 0.03 g/cm3[13] The densities of Kepler-51 b and c have been constrained to be below 0.05 g/cm3 (expected value 0.03 g/cm3 for each). The density of Kepler-51d is determined to be 0.046±0.009 g/cm3.[13]
Hottest Kepler-70b Kepler-70 >7,000 K[14]
Coldest OGLE-2016-BLG-1195Lb OGLE-2016-BLG-1195L 31 K
Highest albedo Kepler-1658 b Kepler-1658 0.758[15](geometric albedo)
Lowest albedo TrES-2b GSC 03549-02811 Geometric albedo < 1%[16] Best-fit model for albedo gives 0.04% (0.0004)[16]
Youngest Proplyd 133-353 Proplyd 133-353 0.5 Myr[17][18] The upper mass limit (13 Jupiter masses) may make this a brown dwarf.
Oldest PSR B1620-26 b PSR B1620-26 13 Gyr Orbits in a circumbinary orbit around two stellar remnants – a pulsar and a white dwarf. Kapteyn b is the oldest potentially habitable exoplanet at 11 Gyr.[19]

Orbital characteristics
Title Planet Star Data Notes
Longest orbital period
(Longest year)		 2MASS J2126-8140 TYC 9486-927-1 ~1,000,000 years GU Piscium b previously held record at 163,000 years.
Shortest orbital period
(Shortest year)		 SWIFT J1756.9-2508 b SWIFT J1756.9-2508 48 minutes, 56.5 seconds[20] K2-137b has the shortest orbit around a main-sequence star (an M dwarf) at 4.31 hours.[21]
Most eccentric orbit HD 20782 b[22] HD 20782 0.956±0.004 [23]Record among confirmed planets. Putative satellite of VB 10 may have higher eccentricity of 0.98.[24]
Largest orbit around a single star 2MASS J2126-8140 TYC 9486-927-1 ~5,800 AU The upper mass limit (13 Jupiter masses) may make this a brown dwarf. Next largest are CVSO 30 c with ~660 AU (unconfirmed) and HD 106906 b[25][26] with ~650 AU
Smallest orbit WD 1202-024 B[27] WD 1202-024 0.0021 AU
Smallest orbit around binary star Kepler-47b Kepler-47AB ≃0.3 AU [28]
Smallest ratio of semi-major axis of a planet orbit to binary star orbit Kepler-16b Kepler-16AB 3.14 ± 0.01 [29]
Largest orbit around binary star DT Virginis c DT Virginis 1,168 AU Star system is also known as Ross 458 AB. The planet was eventually confirmed to be below deuterium burning limit but its formation origin is unknown.
Largest orbit around a single star in a multiple star system Fomalhaut b Fomalhaut 115 AU The second stellar component of the system, TW Piscis Austrini, has a semi-major axis of 57,000 AU from Fomalhaut and the third stellar component, LP 876-10 orbits 158,000 AU away from Fomalhaut.
Largest distance between binary stars with a circumbinary planet FW Tauri AB b FW Tau AB ≈11 AU FW Tauri AB b orbits at a distance of 150-300 AU.[30]
Closest orbit between stars with a planet orbiting one of the stars OGLE-2013-BLG-0341LBb OGLE-2013-BLG-0341LB ~12–17 AU
(10 or 14 AU projected distance)[31]		 OGLE-2013-BLG-0341L b's semi-major axis is 0.7 AU.[31]
Smallest semi-major axis difference between consecutive planets Kepler-70b and Kepler-70c[14] Kepler-70 0.0016 AU (about 240,000 km) During closest approach, Kepler-70c would appear 5 times the size of the Moon in Kepler-70b's sky.
Smallest semi-major axis ratio between consecutive planets Kepler-36b and Kepler-36c Kepler-36 11% Kepler-36b and c have semi-major axes of 0.1153 AU and 0.1283 AU respectively, c is 11% further from star than b .
Largest semi-major axis difference between consecutive planets PTFO 8-8695 / CVSO 30 b and CVSO 30 c CVSO 30 ~662 AU (about 99,000,000,000 km) Currently c is at (least) 127 times the separation of Sun-Jupiter from b or 22 times Sun-Neptune (outer solar system planet), b may be large sunspots instead
Largest semi-major axis ratio between consecutive planets PTFO 8-8695 b / CVSO 30 b and CVSO 30 c CVSO 30 7,900,000% PTFO 8-8695 b / CVSO 30 b and CVSO 30 c have semi-major axes of 0.0084 AU and 662 AU respectively. c is 78,998 times further from the star than b. b may be large sunspots instead.

Stellar characteristics
Title Planet Star Data Notes
Highest metallicity HD 126614 Ab HD 126614 A +0.56 dex Located in a triple star system.
Lowest metallicity Kapteyn b Kapteyn's Star −0.99±0.04 dex BD+20°2457 may be the lowest metallicity planet host ([Fe/H]=−1.00), however the proposed planetary system is dynamically unstable.[32] After Kapteyn's Star, the next lowest-metallicity system is Kepler-271, at -0.951 dex. Planets were announced around even the extremely low metallicity stars HIP 13044 and HIP 11952, however these claims have since been disproven.[33]
Highest stellar mass HD 13189 b[34] HD 13189[34] 4.5±2.5 M☉[34] Margin of error means the star NGC 4349-127 with a stellar mass of 3.9 M☉ is potentially the most massive known planet-harboring star.[35]

Mirfak (8.4 M☉ hypothetically has one planet, but this remains unproven. The extremely massive stars R66 (70 M☉) and R126 (30 M☉) have protoplanetary disks but it is unknown if there are planets in this system.

Lowest stellar mass (main sequence) 2MASS J1119-1137 2MASS J1119–1137 0.0033 M☉ The system 2MASS J1119-1137 AB is a pair of binary rogue planets approximately 3.7 Jupiter masses each.[36]

The least massive main sequence star with known planets is OGLE-2016-BLG-1195L, at 0.078 M☉.

Lowest stellar mass (main sequence star) VHS 1256-1257 b VHS 1256-1257 0.07 M☉
Lowest stellar mass (brown dwarf) 2M J044144 b[37] 2M J044144[37] 0.02 M☉[37]
Largest stellar radius R Leonis b R Leonis 299 or 320-350 R☉[38][39] Star is a Mira variable.
Smallest stellar radius (main sequence star) VB 10 b VB 10 0.102 R☉[40]
Smallest stellar radius (brown dwarf) 2M 0746+20 b[41] 2M 0746+20 0.089 (± 0.003) R☉ Planet's mass is very uncertain at 30.0 (± 25.0) Mjup.
Smallest stellar radius (pulsar) PSR J1719-1438 b[42] PSR J1719-1438 0.04 R☉
Oldest star HD 164922 b HD 164922[43] 13.4 billion years[43]
Hottest star with a planet NY Virginis b NY Virginis[44] 33,247 K This star is a subdwarf B star and has a red dwarf companion of 0.14 solar masses with a semi-major axis of slightly under 4 million kilometers from the primary component. The NN Serpentis system has two exoplanets (NN Serpentis c and NN Serpentis d), with the star at ~57,000K.
Hottest main-sequence star with a planet Fomalhaut b Fomalhaut[45] 8,590 K HIP 78530 has a surface temperature of 10,500K, but it is uncertain whether the orbiting companion is a brown dwarf or planet.
Coldest star with a planet TRAPPIST-1b, c, d, e, f, g, and h. TRAPPIST-1 2,511 K Technically Oph 162225-240515, CFBDSIR 1458+10, and WISE 1217+1626 are colder, but are classified as brown dwarfs.

System characteristics
Title System(s) Planet(s) Star(s) Notes
System with most planets Kepler-90 8[46] 1 Star HD 10180 has 6 confirmed and 3 unconfirmed planets.[47][48]
System with most planets in habitable zone TRAPPIST-1 7 1 Four planets in this system (d, e, f and g) orbit within the habitable zone.[49]
System with most stars Kepler-64 PH1b (Kepler-64b) 4 PH1b has a circumbinary orbit.
Multiplanetary system with smallest mean semi-major axis (planets are nearest to their star) Kepler-42
Kepler-70		 b, c, d
b, c, d?		 1
1		 Kepler-42 b, c, and d have a semimajor axis of only 0.0116, 0.006, and 0.0154 AU, respectively.
Kepler-70 b, c, and d (unconfirmed) have a semimajor axis of only 0.006, 0.0076, and ~0.0065 AU, respectively.
Multiplanetary system with largest mean semi-major axis (planets are farthest from their star) HR 8799 b, c, d, e 1 HR 8799 b, c, d, and e have a semimajor axis of 68, 38, 24, and 14.5 AU, respectively.
Multiplanetary system with smallest range of semi-major axis (smallest difference between the star's nearest planet and its farthest planet) Kepler-70 b, c, d? 1 Kepler-70 b, c, and d (unconfirmed) have a semimajor axis of only 0.006, 0.0076, and ~0.0065 AU, respectively. The separation between closest and furthest is only 0.0016 AU.
Multiplanetary system with largest range of semi-major axis (largest difference between the star's nearest planet and its farthest planet) HR 8799 b, c, d, e 1 HR 8799 b, c, d, and e have a semimajor axis of 68, 38, 24, and 14.5 AU, respectively. The separation between closest and furthest is 53.5 AU.
Multiplanetary system with smallest mean difference in semi-major axis between neighboring planets (orbits are most closely spaced to each other)
Multiplanetary system with largest mean semi-major axis between neighboring planets (orbits are most spread out with respect to each other)
System with smallest total planetary mass Kepler-444 b, c, d, e, f 1 The planets in the Kepler-444 system have radii of 0.4, 0.497, 0.53, 0.546, and 0.741 Earth radii respectively. Due to their size and proximity to Kepler-444, these must be rocky planets, with masses close to that of Mars. For comparison, Mars has a mass of 0.105 Earth masses and a radius of 0.53 Earth radii.
System with largest total planetary mass Kepler-52? b, c, d 1 Kepler-52 b and c have masses of 8.7 and 10.41 Jupiter Masses, respectively. The mass of Kepler-52 d is not known.
System with smallest ratio of total planetary mass to stellar mass
System with largest ratio of total planetary mass to stellar mass
Multiplanetary system with smallest mean planetary mass Kepler-444 b, c, d, e, f 1 The planets in the Kepler-444 system have radii of 0.4, 0.497, 0.53, 0.546, and 0.741 Earth radii respectively. Due to their size and proximity to Kepler-444, these must be rocky planets, with masses close to that of Mars. For comparison, Mars has a mass of 0.105 Earth masses and a radius of 0.53 Earth radii.
Multiplanetary system with smallest ratio of mean planetary mass to stellar mass
Multiplanetary system with largest mean planetary mass Kepler-52? b, c, d 1 Kepler-52 b and c have masses of 8.7 and 10.41 Jupiter Masses, respectively. The mass of Kepler-52 d is not known.
Multiplanetary system with largest ratio of mean planetary mass to stellar mass
Multiplanetary system with smallest range in planetary mass, log scale (smallest proportional difference between the most and least massive planets) Teegarden's Star b, c 1 Teegarden b and c are estimated to have masses of 1.05 and 1.11 Earth masses, respectively.
Multiplanetary system with largest range in planetary mass, log scale (largest proportional difference between the most and least massive planets) Solar System Mercury, Jupiter 1 Mercury and Jupiter have a mass ratio of 5,750 to 1. Kepler-37 d and b may have a mass ratio between 500 and 1000, and Gliese 676 c and d have a mass ratio of 491.

See also

Notes

    References
    1. "HEC: Top 10 Exoplanets". University of Puerto Rico at Arecibo. 5 December 2015. Retrieved 1 August 2017.
    2. Schneider, J. "Notes for star PA-99-N2". The Extrasolar Planets Encyclopaedia. Retrieved 6 August 2010.
    3. Dai, Xinyu; Guerras, Eduardo (2 February 2018). "Probing Extragalactic Planets Using Quasar Microlensing". The Astrophysical Journal. 853 (2): L27. arXiv:1802.00049. Bibcode:2018ApJ...853L..27D. doi:10.3847/2041-8213/aaa5fb. ISSN 2041-8213.
    4. "Astronomers Claim to Find Population of Rogue Exoplanets in Distant Galaxy". Science News.
    5. "Exoplanet-catalog-Exoplanet exploration-Kepler-1606b".
    6. Lee, T. A. (October 1970), "Photometry of high-luminosity M-type stars", Astrophysical Journal, 162: 217, Bibcode:1970ApJ...162..217L, doi:10.1086/150648
    7. "NASA, ESA Telescopes Find Evidence for Asteroid Belt Around Vega" (Press release). Whitney Clavin, NASA. 8 January 2013. Retrieved 4 March 2013.
    8. "GU Psc b". The Extrasolar Planet Encyclopaedia.
    9. "The Extrasolar Planet Encyclopaedia — Catalog Listing". exoplanet.eu. Retrieved 4 May 2019.
    10. Quanz, Sasch P.; Amara, Adam; Meyer, Michael P.; Kenworthy, Matthew P.; et al. (2014). "Confirmation and characterization of the protoplanet HD100546 b - Direct evidence for gas giant planet formation at 50 au". Astrophysical Journal. 807 (1): 64. arXiv:1412.5173. Bibcode:2015ApJ...807...64Q. doi:10.1088/0004-637X/807/1/64.
    11. "Planet SDSS J1228+1040 b". exoplanet.eu. Retrieved 5 August 2019.
    12. Marcy, Geoffrey W.; Isaacson, Howard; Howard, Andrew W.; Rowe, Jason F.; Jenkins, Jon M.; Bryson, Stephen T.; Latham, David W.; Howell, Steve B.; Gautier III, Thomas N.; Batalha, Natalie M.; Rogers, Leslie A. (13 January 2014). "Masses, Radii, and Orbits of Small Kepler Planets: The Transition from Gaseous to Rocky Planets". The Astrophysical Journal Supplement Series. 210 (2): 20. doi:10.1088/0067-0049/210/2/20. hdl:1721.1/92945. ISSN 0067-0049.
    13. Very Low-Density Planets around Kepler-51 Revealed with Transit Timing Variations and an Anomaly Similar to a Planet-Planet Eclipse Event: Kento Masuda
    14. Charpinet, S.; et al. (21 December 2011). "A compact system of small planets around a former red-giant star". Nature. 480 (7378): 496–499. Bibcode:2011Natur.480..496C. doi:10.1038/nature10631. ISSN 1476-4687. PMID 22193103.
    15. "The Extrasolar Planet Encyclopaedia — Kepler-1658 b". exoplanet.eu. Retrieved 8 December 2020.
    16. David M. Kipping; et al. (2011). "Detection of visible light from the darkest world" (PDF). Monthly Notices of the Royal Astronomical Society. 417 (1): L88–L92. arXiv:1108.2297. Bibcode:2011MNRAS.417L..88K. doi:10.1111/j.1745-3933.2011.01127.x. Archived from the original (PDF) on 17 March 2012. Retrieved 12 August 2011.
    17. Fang, Min; Kim, Jinyoung Serena; Pascucci, Ilaria; Apai, Dániel; Manara, Carlo Felice (12 December 2016). "A candidate planetary-mass object with a photoevaporating disk in Orion". The Astrophysical Journal. 833 (2): L16. arXiv:1611.09761. doi:10.3847/2041-8213/833/2/L16. ISSN 2041-8213.
    18. "The Extrasolar Planet Encyclopaedia — Proplyd 133-353". exoplanet.eu. Retrieved 30 March 2019.
    19. "Introducing Earth's bigger, older brother: planet Kapteyn b". 14 June 2014.
    20. "The Extrasolar Planet Encyclopaedia — SWIFT J1756-2508". exoplanet.eu. Retrieved 22 August 2018.
    21. "The Extrasolar Planet Encyclopaedia — K2-137 b." Exoplanet.eu. 2018.
    22. "HD 20781 b". Open Exoplanet Catalogue. Retrieved 20 October 2018.
    23. "The Extrasolar Planet Encyclopaedia — HD 20782 b". exoplanet.eu. Retrieved 4 May 2019.
    24. "The Extrasolar Planet Encyclopaedia — VB 10 b". exoplanet.eu. Retrieved 12 February 2020.
    25. Chow, Denise (6 December 2013). "Giant Alien Planet Discovered in Most Distant Orbit Ever Seen". space.com. Retrieved 8 December 2013.
    26. Bailey, Vanessa; et al. (January 2014). "HD 106906 b: A planetary-mass companion outside a massive debris disk". The Astrophysical Journal Letters. 780 (1): L4. arXiv:1312.1265. Bibcode:2014ApJ...780L...4B. doi:10.1088/2041-8205/780/1/L4. L4.
    27. Bailes, M.; Bates, S. D.; Bhalerao, V.; Bhat, N. D. R.; Burgay, M.; Burke-Spolaor, S.; d'Amico, N.; Johnston, S.; Keith, M. J.; et al. (2011). "Transformation of a Star into a Planet in a Millisecond Pulsar Binary" (PDF). Science. 333 (6050): 1717–20. arXiv:1108.5201. Bibcode:2011Sci...333.1717B. CiteSeerX 10.1.1.753.7160. doi:10.1126/science.1208890. PMID 21868629.
    28. OROSZ J.; WELSH W.; CARTER J.; FABRYCKY D.; COCHRAN W.; et al. (2012). "Kepler-47: A Transiting Circumbinary Multi-Planet System". Science. 337 (6101): 1511–4. arXiv:1208.5489. Bibcode:2012Sci...337.1511O. doi:10.1126/science.1228380. PMID 22933522.
    29. Laurance R. Doyle; Joshua A. Carter; Daniel C. Fabrycky; Robert W. Slawson; Steve B. Howell; Joshua N. Winn; Jerome A. Orosz; Andrej Prsa; William F. Welsh; et al. (2011). "Kepler-16: A Transiting Circumbinary Planet". Science. 333 (6049): 1602–1606. arXiv:1109.3432. Bibcode:2011Sci...333.1602D. doi:10.1126/science.1210923. PMID 21921192.
    30. Kraus, Adam; J. Ireland, Michael; A. Cieza, Lucas; Hinkley, Sasha; J. Dupuy, Trent; P. Bowler, Brendan; C. Liu, Michael (2 January 2014). "Three Wide Planetary-Mass Companions to FW Tau, ROXs 12, and ROXs 42B". Science. 781 (1): 1311. arXiv:1311.7664. Bibcode:2014ApJ...781...20K. doi:10.1088/0004-637X/781/1/20.
    31. Gould, A.; et al. (3 July 2014). "A terrestrial planet in a ~1-AU orbit around one member of a 15-AU binary". Science. 345 (6192): 46–49. arXiv:1407.1115. Bibcode:2014Sci...345...46G. doi:10.1126/science.1251527. ISSN 0036-8075. PMID 24994642. these projected separations are good proxies for the semi-major axis (afterupward adjustment by to correct for projection effects)CS1 maint: numeric names: authors list (link)
    32. http://adsabs.harvard.edu/abs/2014MNRAS.439.1176H
    33. http://adsabs.harvard.edu/abs/2014A&A...562A.129J
    34. "Notes for planet HD 13189 b". The Extrasolar Planets Encyclopaedia. Retrieved 15 September 2015.
    35. "Notes for planet NGC 4349-127 b". The Extrasolar Planets Encyclopaedia. Retrieved 28 August 2017.
    36. "Notes for planet 2MASSS J1119-1137 AB". The Extrasolar Planets Encyclopaedia. Retrieved 29 August 2017.
    37. Schneider, J. "Notes for planet 2M J044144 b". The Extrasolar Planets Encyclopaedia. Archived from the original on 22 November 2010. Retrieved 28 November 2010.
    38. De Beck, E.; Decin, L.; De Koter, A.; Justtanont, K.; Verhoelst, T.; Kemper, F.; Menten, K. M. (2010). "Probing the mass-loss history of AGB and red supergiant stars from CO rotational line profiles. II. CO line survey of evolved stars: Derivation of mass-loss rate formulae". Astronomy and Astrophysics. 523: A18. arXiv:1008.1083. Bibcode:2010A&A...523A..18D. doi:10.1051/0004-6361/200913771.
    39. Fedele; et al. (2005). "The K -Band Intensity Profile of R Leonis Probed by VLTI/VINCI". Astronomy and Astrophysics. 431 (3): 1019–1026. arXiv:astro-ph/0411133. Bibcode:2005A&A...431.1019F. doi:10.1051/0004-6361:20042013.
    40. Linsky, Jeffrey L.; Wood, Brian E.; Brown, Alexander; Giampapa, Mark S.; Ambruster, Carol (December 1995). "Stellar Activity at the End of the Main Sequence: GHRS Observations of the M8 Ve Star VB 10". The Astrophysical Journal. 455: 670. Bibcode:1995ApJ...455..670L. doi:10.1086/176614. hdl:2060/19970022983. ISSN 0004-637X.
    41. "The Extrasolar Planet Encyclopaedia — 2M 0746+20 b". exoplanet.eu.
    42. "PSR J1719-1438 b". caltech.edu.
    43. "HD 164922 b". The Extrasolar Planets Encyclopaedia. Retrieved 19 December 2012.
    44. Joe Bauwens (29 December 2011). "Sciency Thoughts: Planets in the NY Virginis system". sciencythoughts.blogspot.com.
    45. "Fomalhaut b". The Extrasolar Planets Encyclopaedia. Retrieved 30 March 2013.
    46. Northon, Karen (14 December 2017). "Artificial Intelligence, NASA Data Used to Discover Exoplanet". NASA. Retrieved 14 December 2017.
    47. "HD 10180 i". The Extrasolar Planets Encyclopaedia. Retrieved 24 December 2012.
    48. "HD 10180 j". The Extrasolar Planets Encyclopaedia. Retrieved 24 December 2012.
    49. "NASA telescope reveals largest batch of Earth-size, habitable-zone planets around single star". Exoplanet Exploration: Planets Beyond our Solar System. nasa.gov. 21 February 2017. Retrieved 14 December 2017.
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