The following are lists of extremes among the known exoplanets. The properties listed here are those for which values are known reliably. It is important to note that the study of exoplanets is one of the most dynamic emerging fields of science, and these values may change wildly as new discoveries are made.
Title | Planet | Star | Data | Notes |
---|---|---|---|---|
Most distant discovered | SWEEPS-11 / SWEEPS-04 | SWEEPS J175902.67−291153.5 / SWEEPS J175853.92−291120.6 | 27,710 light-years [1] | Several candidate extragalactic planets have been detected. The most distant potentially habitable planet confirmed is Kepler-1606b, at 2,870 light-years distant, [2] although the unconfirmed planet KOI-5889.01 is over 5,000 light-years distant. On 31 March 2022, K2-2016-BLG-0005Lb was reported to be the most distant exoplanet discovered by Kepler telescope, at 17,000 light-years away. [3] |
Least distant | Proxima Centauri b, c and d | Proxima Centauri | 4.25 light-years | Proxima Centauri b and d are the closest rocky exoplanets, b is the closest potentially habitable exoplanet known, and c is the closest mini-Neptune 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 | CT Chamaeleontis b | CT Chamaeleontis | 622 light-years [4] | The disputed planet candidate CVSO 30 c may be more distant, at 1,200 light-years. |
Closest directly visible | COCONUTS-2b | L 34-26 | 35.5 light-years [4] | WISE 1217+1626 B is closer, but is generally considered a brown dwarf. Proxima Centauri c (confirmed in 2020 using archival Hubble data from 1995+) may have been directly imaged. [5] |
Star with the brightest apparent magnitude with a planet | Pollux b | Pollux [6] | Apparent magnitude is 1.14 | Alpha Centauri A (apparent magnitude 0.01) has an unconfirmed planet candidate. The evidence of planets around Vega with an apparent magnitude of 0.03 is strongly suggested by circumstellar disks surrounding it. [7] As of 2021 [update] , a candidate planet around Vega has been detected. [8] Aldebaran (apparent magnitude varies between 0.75 and 0.95) was suspected to have a candidate planet, however later studies found the existence of planet inconclusive. [9] |
Star with the faintest apparent magnitude with a planet | MOA-bin-29Lb | MOA-bin-29L | Apparent magnitude is 44.61 [4] | |
Largest angular distance separation from its host star | COCONUTS-2b | COCONUTS-2 | 594 arcseconds [10] |
Title | Planet | Star | Data | Notes |
---|---|---|---|---|
Least massive | PSR B1257+12 b | PSR B1257+12 | 0.020±0.002 M🜨 [4] | The extrasolar planetesimal WD 1145+017 b is less massive, at 0.00067 ME. [10] |
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 (the border between them approximately from 13 to 80 MJ). It is estimated the largest planets are approximately a dozen Jupiter masses. | |||
Largest radius | PDS 70 b | PDS 70 | 2.09+0.23 −0.32 –2.72+0.39 −0.34RJ. [11] | Proplyd 133-353 at 7.4±0.3 – 8±1.1 RJ [12] [lower-alpha 1] could be a sub-brown dwarf or a rogue planet, with a photoevaporating disk. HAT-P-67b has the largest accurately measured radius, at 2.085+0.096 |
Smallest radius | Kepler-37b | Kepler-37 | 0.296±0.037 R🜨 [4] | The extrasolar planetesimals SDSS J1228+1040 b [14] and WD 1145+017 b are smaller. |
Most dense | TOI-4603b | HD 245134 | 14.1+1.7 −1.6 g/cm3 [15] | TOI-4603b has a mass of 12.89+0.58 −0.57 MJ and a radius of 1.042+0.038 −0.035 RJ. [16] KELT-1b is denser, with 22.1+5.62 Kepler-131c might be more dense at 77.7+55 |
Least dense | Kepler-51c, b and/or possibly d [19] | Kepler-51 [19] | ~ 0.03 g/cm3 [19] | 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. [19] |
Hottest (irradiated hot Jupiter) | KELT-9b | KELT-9 | 4,050±180 K [4] (3777 °C) | The unconfirmed planets Kepler-70b and Kepler-70c may be hotter, both at >6,800 K. [20] |
Hottest (self-luminous) | AB Aurigae b | AB Aurigae | 3,800 K (3,530 °C) [21] | |
Coldest | OGLE-2005-BLG-390Lb | OGLE-2005-BLG-390L | 50 K (−223.2 °C) [22] | The disputed planet Proxima Centauri c may be cooler, at 39 K (−234.2 °C). [23] |
Highest albedo | LTT 9779 b | LTT 9779 | 0.8 [24] | For comparison, Earth is 0.3 and Venus is 0.76. |
Lowest albedo | TrES-2b | GSC 03549-02811 | Geometric albedo < 1% [25] | Best-fit model for albedo gives 0.04% (0.0004). [20] |
Youngest | ROXs 42Bb | ROXs 42B | 2.75 Myr [4] | Proplyd 133-353 is younger, at 0.5 Myr [26] [27] , but it could be a sub-brown dwarf rather than a rogue planet. [26] 2MASS J04414489+2301513 b is listed as the youngest planet in the NASA Exoplanet Archive, at a age of 1 Myr [4] , but fails the mass ratio criterion of the IAU working definition of an exoplanet; the mass ratio with the primary is smaller than ~1/25 [28] and 'more likely to have produced' 'by cloud core fragmentation' (like a star). [29] K2-33b is the youngest transiting planet, at an age of 9.3 Myr. [30] |
Oldest | WASP-183b | WASP-183 | 14.9±1.7 Gyr [4] | The estimated age of the universe is 13.8 billion years, within the margin of error. |
Title | Planet | Star | Data | Notes |
---|---|---|---|---|
Longest orbital period (Longest year) | COCONUTS-2b | COCONUTS-2 | 1.1 million years [31] | 2MASS J2126–8140 previously held this record at ~900,000 years. |
Shortest orbital period (Shortest year) | PSR J1719-1438 b | PSR J1719-1438 | 2.17695 h (131 minutes) [32] | An unconfirmed planet announced around the pulsar SWIFT J1756.9−2508 may have a shorter orbital period of under an hour. [33] K2-137b has the shortest orbit around a main-sequence star (an M dwarf) at 4.31 hours. [34] |
Most eccentric orbit | HD 20782 b [35] | HD 20782 | 0.956±0.004 | [36] Record among confirmed planets. The disproven planet candidate at VB 10 was thought to have a higher eccentricity of 0.98. [37] HD 80606 b previously held this record at 0.93226+0.00064 −0.00069. |
Highest orbital inclination | HD 204313 e | HD 204313 | 176.092° +0.963° −2.122° | [38] [39] |
Lowest orbital inclination | HD 331093 b | HD 331093 | >0.3704° | [40] [39] HD 43197 c has the lowest orbital inclination that is not a lower limit, of 11.42°+5.388° −3.07°. [39] |
Largest orbit around a single star | COCONUTS-2b | COCONUTS-2 | 7,506+5,205 −2,060 AU [4] | Projected separation of 6,471 AU. [31] Next largest are 2MASS J2126–8140 with 6,900 AU and HD 106906 b [41] with ~738 AU. |
Smallest orbit | PSR J1719-1438 b | PSR J1719−1438 | 0.0044 AU (658,230 km) | [42] |
Smallest orbit around binary star | Kepler-47b | Kepler-47AB | 0.2877+0.0014 −0.0011 AU [4] | [43] |
Smallest ratio of semi-major axis of a planet orbit to binary star orbit | Kepler-16b | Kepler-16AB | 3.14 ± 0.01 | [44] |
Largest orbit around binary star | SR 12 (AB) c | SR 12 AB | ≈1100 AU [45] | SR 12 (AB) c has a mass of 0.013±0.007 M☉ . [45] ROXs 42B (AB) b is lower in mass at 9.0+6 DT Virginis c , also known as Ross 458 (AB) c, at a projected separation of ≈1200 AU, with several mass estimates below the deuterium burning limit, has a latest mass determination of 27±4MJ. [47] |
Largest orbit around a single star in a multiple star system | ROXs 12 b | ROXs 12 | 210±20 AU [4] | |
Largest separation between binary stars with a circumbinary planet | SR 12 (AB) c | SR 12 AB | ≈26 AU [45] | SR 12 (AB) c has a mass of 0.013±0.007 M☉ at a projected separation of ≈1100 AU. [45] FW Tauri b orbits at a projected separation of 330±30 AU around a ≈11 AU separated binary. [48] It was shown to be more likely a 0.1 M☉ star surrounded by a protoplanetary disk than a planetary-mass companion. [49] |
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) [50] | OGLE-2013-BLG-0341L b's semi-major axis is 0.7 AU. [50] |
Smallest semi-major-axis difference between consecutive planets | Kepler-70b and Kepler-70c [20] | Kepler-70 | 0.0016 AU (240,000 km) | During closest approach, Kepler-70c would appear 5 times the size of the Moon in Kepler-70b's sky.[ needs update ] |
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. |
Title | Planet | Star | Data | Notes |
---|---|---|---|---|
Highest metallicity | HD 126614 Ab | HD 126614 A | +0.56 dex | Located in a triple star system. |
Lowest metallicity | K2-344b | K2-344 | −0.95±0.02 dex [4] | BD+20°2457 may be the lowest-metallicity planet host ([Fe/H]=−1.00); however, the proposed planetary system is dynamically unstable. [51] Kapteyn's Star may also be the lowest-metallicity planet host ([Fe/H]=−0.99±0.04), but its planets are most likely artifacts of stellar activity and rotation. [52] Planets were announced around even the extremely low-metallicity stars HIP 13044 and HIP 11952; however, these claims have since been disproven. [53] A brown dwarf or massive gas giant companion was announced around the population II star HE 1523-0901, whose metallicity is −2.65±0.22 dex. [54] While the inclination of the companion is not known, if its orbit is nearly face-on, it would be sufficiently massive to become a red dwarf instead. [55] |
Highest stellar mass | Mu2 Scorpii b | Mu2 Scorpii | 9.1±0.3 M☉ [56] | M51-ULS-1b, listed as a candidate planet with 4 sigma confidence, may be the planet with the highest-mass host star. The host is a massive O-class supergiant and a black hole orbiting each other at 0.8 AU, with a combined system mass of >60 solar masses. The planet is a Saturn-sized (0.72 Jupiter radii) object orbiting the black-hole/supergiant binary at 10 AU. The host stars giving off a combined 1 million solar luminosities, the planet receives the equivalent irradiation of 51 Pegasi b, which orbits its star at 0.045 AU. M51-ULS-1b would also be one of the youngest planets ever discovered, with a system age of <10 million years according to evolutionary models. [57] The stars R126 (HD 37974) and R66 (HD 268835) in the Large Magellanic Cloud have masses of 70 and 30 solar masses and have dust discs but no planets have been detected yet. |
Lowest stellar mass (main sequence) | KMT-2021-BLG-1554Lb | KMT-2021-BLG-1554L | 0.08+0.013 −0.014 M☉ [39] | The mass of this star is near to the hydrogen burning limit. KMT-2016-BLG-2142L have a lower mass, of 0.073+0.117 |
Lowest stellar mass (brown dwarf) | 2MASS J1119-1137 B | 2MASS J1119–1137 A | 0.0033 M☉ | The system 2MASS J1119-1137 AB is a pair of binary rogue planets approximately 3.7 MJup each. [58] |
Largest stellar radius | HD 240237 b | HD 240237 | 71.23±17.07 R☉ [4] | HD 81817 and Mirach (β Andromedae) are larger, at 83.8±7.8 R☉ [4] and 86.4 R☉ [59] respectively, but their planetary companions may actually be brown dwarfs, and in the case of HD 81817 its companion may be sufficiently massive to be a red dwarf. R Leonis (299 or 320-350 R☉) [60] [61] has a candidate planet. It is a Mira variable. The stars R126 and R66 in the Large Magellanic Cloud have radius of 78 R☉ and 131 R☉ [62] and have dust discs but no planets have been detected yet. |
Smallest stellar radius (main sequence star) | TRAPPIST-1 planets | TRAPPIST-1 | 0.1192±0.0013 R☉ [63] | VB 10 (0.102 R☉) [64] has a disproven planet candidate. |
Smallest stellar radius (brown dwarf) | 2M 0746+20 b [65] | 2M 0746+20 | 0.089 (± 0.003) R☉ | Planet's mass is very uncertain at 30.0 (± 25.0) MJup. |
Smallest stellar radius (stellar remnant) | PSR B0943+10 b and c; [66] [67] [68] PSR B1257+12 b, c and d | PSR B0943+10 and PSR B1257+12 | 0.000007187 R☉ (5 km) [69] [70] [lower-alpha 2] | Both stars (PSR B0943+10 and PSR B1257+12) have the same size. PSR B0943+10 may be a quark star. If so, its radius is predicted to be 2.6 km. [69] |
Highest stellar luminosity | Beta Andromedae b | Mirach | 1675 L☉ | [71] [39] With a mass of 28.26+2.05 −2.17 MJ, the planet is likely a brown dwarf. Beta Cancri, with a luminosity of 794 L☉, is the most luminous star to host a planet (Beta Cancri b) that is not a potential brown dwarf. [72] [39] The stars R126 and R66 in the Large Magellanic Cloud have luminosity of 1400000 L☉ and 320000 L☉ [62] and have dust discs but no planets have been detected yet. |
Lowest stellar luminosity (main sequence star) | TRAPPIST-1 planets | TRAPPIST-1 | 0.0005495 L☉ | [73] [39] |
Oldest star | WASP-183b | WASP-183 | 14.9±1.7 Gyr [4] | The estimated age of the universe is 13.8 billion years, within the margin of error. |
Hottest star with a planet | NSVS 14256825 b | NSVS 14256825 | 40,000 K [74] | NN Serpentis is hotter, with a temperature of 57,000 K, [4] but the existence of its planets is disputed. [75] |
Hottest main-sequence star with a planet | b Centauri b | b Centauri | 18,310±320 K [76] | V921 Scorpii b orbits a hotter star, at 30,000 K. Its host star is a 20-solar-mass B0IV-class subgiant. [77] However, at 60 Jupiter masses, it is not considered a planet under most definitions. The candidate planet M51-ULS-1b's supergiant primary is an O5-class supergiant with an estimated surface temperature of 40,000 K, but as the star is a supergiant, does not count as on the main sequence. |
Coolest star with a planet | TRAPPIST-1 planets | TRAPPIST-1 | 2,511 K | Technically Oph 162225-240515, CFBDSIR 1458+10 and WISE 1217+1626 are cooler, but are classified as brown dwarfs. |
Title | System(s) | Planet(s) | Star(s) | Notes |
---|---|---|---|---|
System with most planets | Kepler-90 | 8 | 1 | Tau Ceti currently has no confirmed planetary companion, although it has been proposed that the number of orbiting planets may be 8, 9 or even 10. [78] The four planets Tau Ceti e, f, g and h are considered as strong candidates. [79] HD 10180 has six confirmed planets and potentially three more planets. [80] |
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. [81] |
System with most stars | Kepler-64 | PH1b (Kepler-64b) | 4 | PH1b has a circumbinary orbit. 30 Arietis Bb was believed to be either brown dwarf or a massive gas giant in a quadruple star system until later studies revealed a true mass well above 80 MJup. [82] |
Multiplanetary system with smallest mean semi-major axis (planets are nearest to their star) | Kepler-42 | b, c, d | 1 | Kepler-42 b, c and d have a semi-major axis of only 0.0116, 0.006 and 0.0154 AU, respectively. Kepler-70 b, c and d (all unconfirmed and disputed) have a semi-major 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) | TYC 8998-760-1 | b, c | 1 | TYC 8998-760-1 b and c have a semi-major axis of 162 and 320 AU, respectively. [4] |
Multiplanetary system with smallest range of semi-major axis (smallest difference between the star's nearest planet and its farthest planet) | Kepler-42 | b, c, d | 1 | Kepler-42 b, c and d have a semi-major axis of only 0.0116, 0.006 and 0.0154 AU, respectively. The separation between closest and furthest is only 0.0094 AU. Kepler-70 b, c and d (all unconfirmed and disputed) have a semi-major axis of only 0.006, 0.0076 and ~0.0065 AU, respectively. The separation between closest and furthest is only 0.0016 AU (239,356 km). |
Multiplanetary system with largest range of semi-major axis (largest difference between the star's nearest planet and its farthest planet) | TYC 8998-760-1 | b, c | 1 | TYC 8998-760-1 b and c have a semi-major axis of 162 and 320 AU, respectively. [4] The separation between closest and furthest is 158 AU. |
System with smallest total planetary mass | Kepler-444 | b, c, d, e, f | 3 | 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 | Nu Ophiuchi | b, c | 1 | Nu Ophiuchi b and c have masses of 22.206 and 24.662 Jupiter masses, respectively. [4] They may be brown dwarfs. |
Multiplanetary system with smallest mean planetary mass | Kepler-444 | b, c, d, e, f | 3 | 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 largest mean planetary mass | Nu Ophiuchi | b, c | 1 | Nu Ophiuchi b and c have masses of 22.206 and 24.662 Jupiter masses, respectively. [4] They may be brown dwarfs. |
Exo-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. |
Exo-multiplanetary system with largest range in planetary mass, log scale (largest proportional difference between the most and least massive planets) | Kepler-37 | b, d | 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 1,000, and Gliese 676 c and d have a mass ratio of 491. |
these projected separations are good proxies for the semi-major axis (afterupward adjustment by to correct for projection effects)
{{cite web}}
: CS1 maint: archived copy as title (link)BD−10°3166 is a K-type main sequence star approximately 268 light-years away in the constellation of Crater. It was inconspicuous enough not be included in the Draper catalog (HD). The Hipparcos satellite also did not study it, so its true distance is poorly known. The distance measured by the Gaia spacecraft of 268 light years rules out a suggested companion star, LP 731-076, being its true binary star companion.
Kepler-17 is a main-sequence yellow dwarf star that is much more active than the Sun with starspots covering roughly 6% of its surface. Starspots are long-lived, with at least one persisting for 1400 days.
GJ 3512 is a nearby star in the northern circumpolar constellation of Ursa Major. It is invisible to the naked eye but can be observed using a telescope, having an apparent visual magnitude of +15.05. The star is located at a distance of 31 light-years from the Sun based on parallax. It has a high proper motion, traversing the celestial sphere at the rate of 1.311″ yr−1. The measurement of the star's radial velocity is poorly constrained, but it appears to be drifting further away at a rate of ~8 km/s.
K2-32 is a G9-type main sequence star slightly smaller and less massive than the sun. Four confirmed transiting exoplanets are known to orbit this star. A study of atmospheric escape from the planet K2-32b caused by high-energy stellar irradiation indicates that the star has always been a very slow rotator.
WASP-76b is an exoplanet classified as a Hot Jupiter. It is located in the constellation Pisces and orbits its host star, WASP-76, at a distance of approximately 0.033 astronomical units (AU). The orbital period of WASP-76b is approximately 1.8 days. Its mass is about 0.92 times that of Jupiter. The discovery of WASP-76b took place on October 21, 2013, and it is currently the only known planet in the WASP-76 system as of 2022. The equilibrium temperature of WASP-76b is estimated to be around 2,190 K, However, the measured daytime temperature is higher, reaching approximately 2,500 ± 200 K.
Kepler-411 is a binary star system. Its primary star Kepler-411A is a K-type main-sequence star, orbited by the red dwarf star Kepler-411B on a wide orbit, discovered in 2012.