Below is a list of the largest exoplanets so far discovered, in terms of physical size, ordered by radius.
This list of extrasolar objects may and will change over time because of inconsistency between journals, different methods used to examine these objects and the already extremely hard task of discovering exoplanets, or any other large objects for that matter. Then there is the fact that these objects might be brown dwarfs, sub-brown dwarfs, or not exist at all. Because of this, this list only cites the best measurements to date and is prone to change. Remember, these objects are not stars, and are quite small on a universal or even stellar scale.
The sizes are listed in units of Jupiter radii (71,492 km). All planets listed are larger than 1.7 times the size of the largest planet in the Solar System, Jupiter. Some planets that are smaller than 1.7 RJ have been included for the sake of comparison.
Probably brown dwarfs (based on mass) | |
---|---|
Probably sub-brown dwarfs (based on mass and location) | |
Probably planets (based on mass) |
Illustration | Exoplanet name | Radius (RJ) | Notes |
---|---|---|---|
Size limit for brown dwarfs | 8 [1] | ||
Proplyd 133-353 | 7.4±0.3 –8.0±1.1 [2] [lower-alpha 1] | A candidate rogue planet / sub-brown dwarf with a photoevaporating disk. It is located in the Orion Nebula Cluster. At 500,000 years old, it is one of the youngest exoplanets known. More information about the exoplanet and estimates of its radius are available below: | |
GQ Lupi b | 3.0±0.5, [3] 4.6±1.5, [4] 3.50+1.50 −1.03, [5] 3.77 [6] | 21.5 MJ; at the highest end of this range, it may be classified as a young brown dwarf. | |
DH Tauri b | 2.6±0.7 –2.7±0.8 [7] ; 2.68 [8] | 14.2 MJ; at its largest, it would be classified as a brown dwarf. [8] | |
ROXs 42Bb | 2.43±0.18 –2.55±0.2 [9] | ||
OTS 44 | 2.24 [10] –5.55 [11] | Very likely a brown dwarf [10] or sub-brown dwarf, [11] which it may be the least massive free-floating substellar objects. It is surrounded by a circumstellar disk of dust and particles of rock and ice. | |
The above radii are larger than what planetary evolution theory predicts for hot Jupiters, and are thus potentially unreliable. | |||
Hot Jupiter limit | 2.2 [12] | Theoretical limit for hot Jupiters close to a star, that are limited by tidal heating, resulting in 'runaway inflation' | |
CT Chamaeleontis b | 2.2+0.81 −0.6 [13] | 17 MJ; is likely a brown dwarf. | |
PDS 70 b | 2.09+0.23 −0.32 –2.72+0.39 −0.34 [14] | Possibly the largest known exoplanet. [12] | |
AB Aurigae b | 1.6 [15] - 2.75 [16] | the largest radius of 2.75 RJ is only valid for 1 Myr. Several publications give a higher age, e.g. 1-5 Myr [16] , 4±1 Myr [17] , 6.0+2.5 −1.0 Myr. [18] Also the protoplanet is disputed. [19] [20] | |
HAT-P-67b | 2.085+0.096 −0.071 [21] | 0.34+0.25 −0.19MJ; a very puffy Hot Jupiter. | |
XO-6b | 2.07±0.22 [22] | 4.4 MJ; a very puffy Hot Jupiter | |
HAT-P-41b | 2.05±0.50 [3] | 1.19 MJ; a very puffy Hot Jupiter | |
PDS 70 c | 2.04+0.61 −0.45 [3] | 2 MJ | |
WASP-17b (Ditsö̀) | 1.991±0.081 [23] | Was the largest known planet in 2012. At only 0.486 MJ, this Hot Jupiter is extremely low density at 0.08 g/cm3 which make it is one of the most puffy planet known. This estimate gives also a range from 1.411 RJ to 2.071 RJ. [24] | |
Kepler-435b | 1.99±0.18 [25] | ||
HAT-P-32b | 1.980±0.045, [3] 2.037±0.999 [22] | 0.941 (± 0.166) MJ; a very puffy Hot Jupiter. Other estimates give 1.789±0.025RJ. [26] | |
WASP-12b | 1.937±0.056 [27] 1.900+0.057 −0.055, [28] 1.736±0.056 [29] | This planet is so close to its parent star that its tidal forces are distorting it into an egg shape. As of September 2017, it has been described as "black as asphalt", and as a "pitch black" hot Jupiter as it absorbs 94% of the light that shines on its surface. | |
BD-14 3065 b | 1.926±0.094 [30] | ||
KELT-19 Ab | 1.91±0.11 [31] | ||
51 Pegasi b (Dimidium/Bellerophon) | 1.9±0.3 [32] | First exoplanet to be discovered orbiting a main-sequence star. Prototype hot Jupiter. | |
KELT-9b | 1.891+0.061 −0.055 [33] | The hottest confirmed exoplanet known. | |
HAT-P-65b | 1.89±0.13 [34] | ||
TOI-1518 b | 1.875±0.053 [3] | ||
HAT-P-70b | 1.87+0.15 −0.10 [3] | ||
WASP-121b | 1.865±0.044 [35] | ||
HATS-23b | 1.86+0.3 −0.4 [36] | ||
CFHTWIR-Oph 98 b | 1.86±0.05 [3] | ||
KELT-8b | 1.86+0.18 −0.16 [37] | ||
WASP-76b | 1.83+0.06 −0.04 [38] | The tidally-locked planet where winds move 18,000 km/h, and where molten iron rains from the sky due to daytime temperatures exceeding 2,400 °C (4,350 °F). [39] [40] | |
HAT-P-33b | 1.827±0.29, [41] 1.85±0.49 [3] | ||
TYC 8998-760-1 b | 1.82±0.08 [42] –3.0+0.2 −0.7, [4] | On 22 July 2020, astronomers announced images, for the first-time, of multiple extrasolar bodies orbiting a star, TYC 8998-760-1, nearly identical to the Sun, except for age. TYC 8998-760-1 is only 27 Ma old while the Sun is 4,500 Ma. [43] [44] [45] and its largest orbital body (TYC 8998-760-1 b) is 22 ± 3 MJ; likely making it a brown dwarf. | |
WASP-178b | 1.81±0.09 [3] | ||
Upsilon Andromedae b (Saffar) | 1.8 [46] | ||
Cha 110913-773444 | 1.8 [47] | A rogue planet (Likely a sub-brown dwarf) that is surrounded by a protoplanetary disk. It is one of youngest free-floating substellar objects with 0.5–10 Myr. | |
GSC 06214-00210 b | 1.8±0.5 [3] | 16 MJ, likely brown dwarf | |
TrES-4b | 1.799±0.063 [48] | This planet has a density of 0.2 g/cm3, about that of balsa wood, less than Jupiter's 1.3g/cm3. | |
WASP-122b | 1.792±0.069 [49] | ||
KELT-12b | 1.78+0.17 −0.16 [50] | ||
TOI-640 b | 1.771+0.060 −0.056 [3] | ||
TOI-2193 Ab | 1.77 [51] | ||
TOI-2669b | 1.76±0.16 [52] | ||
Kepler-12b | 1.754+0.031 −0.036 [53] | ||
HATS-26b | 1.75±0.21 [54] | ||
AB Pictoris b | 1.75 [55] | 13.5 MJ, potential brown dwarf | |
KELT-14b | 1.743±0.047 [49] | ||
KELT-15b | 1.74±0.20 [3] | ||
HAT-P-57b | 1.74±0.36 [3] | ||
KELT-20b | 1.735+0.07 −0.075, [56] 1.741+0.069 −0.074 [3] | ||
HAT-P-64b | 1.703±0.070 [3] | ||
WASP-78b | 1.70±0.04, [57] 1.93±0.45 [3] | ||
Qatar-7b | 1.70±0.03 [3] | ||
A few additional examples with radii lower than 1.7 RJ. | |||
KELT-4Ab | 1.699+0.046 −0.045, [3] 1.706+0.085 −0.076 [58] | ||
Kepler-12b | 1.695+0.032 −0.032, [59] 1.754+0.031 −0.036 [3] | ||
WASP-79b (Pollera) | 1.67±0.15, [3] 2.09±0.14 [57] | ||
1RXS 1609b | 1.664, [3] 1.7 [60] | 14+2.0 −3.0MJ; is likely a brown dwarf. | |
WASP-94 Ab | 1.58±0.13, [3] 1.72+0.06 −0.05 [61] | ||
PSO J318.5−22 | 1.53 | An extrasolar object that does not seem to be orbiting any stellar mass, see: rogue planet. | |
HAT-P-40b (Vytis) | 1.52±0.17, [3] 1.730±0.062 [62] | ||
Kepler-13 Ab (KOI-13b) | 1.512±0.035, [3] 2.216±0.087 [63] | Esteves et al. gives also radii of 1.512±0.035 RJ and 2.63+1.04 −0.82 RJ. Batalha et al. calculate 2.03 RJ. [64] | |
Kepler-7b | 1.478 | ||
Beta Pictoris b | 1.46±0.01 | Likely the second most massive object in its namesake system. | |
WASP-88b | 1.46±0.21, [3] 1.7+0.13 −0.07 [65] | ||
HD 209458 b | 1.35 | The first exoplanet whose size was determined. Named after a prominent Egyptian deity, 'Osiris'. | |
HR 8799 c | 1.3 [66] | ||
TrES-2b (Kepler-1b) | 1.272 | Darkest known exoplanet due to an extremely low geometric albedo. It absorbs 99% of light. | |
HD 100546 c | 1.265 [67] | Still disputed. | |
Kepler-39b | 1.22 | One of the most massive exoplanets known. | |
HR 8799 d | 1.2 [68] | ||
HR 8799 b | 1.2 [68] | ||
HR 8799 e | 1.17 [69] | ||
COCONUTS-2b | 1.12±0.04 | The exoplanet with the longest orbital period, of 1100000 years (around one megannum). It is located 7,506 astronomical units (0.11869 ly ) from its star. | |
HR 2562 b | 1.11 | Most massive planet with a mass of 30 MJ, although according to most definitions of planet, it may be too massive to be a planet, and may be a brown dwarf instead. | |
HIP 11915 b | 1 [70] | This exoplanet is an analogue to Jupiter, having a similar radius, mass and temperature, and it is orbiting a star analogous to the Sun. | |
Jupiter | 1 69,911 km [71] | Largest planet in the Solar System, by radius and mass. [72] Reported for reference. | |
The Hungarian Automated Telescope Network (HATNet) project is a network of six small fully automated "HAT" telescopes. The scientific goal of the project is to detect and characterize extrasolar planets using the transit method. This network is used also to find and follow bright variable stars. The network is maintained by the Center for Astrophysics | Harvard & Smithsonian.
WASP-4b is an exoplanet, specifically a hot Jupiter, approximately 891 light-years away in the constellation of Phoenix.
WASP-11/HAT-P-10 is a binary star. It is a primary main-sequence orange dwarf star. Secondary is M-dwarf with a projected separation of 42 AU. The system is located about 424 light-years away in the constellation Aries.
WASP-33b is an extrasolar planet orbiting the star HD 15082. It was the first planet discovered to orbit a Delta Scuti variable star. With a semimajor axis of 0.026 AU and a mass likely greater than Jupiter's, it belongs to the hot Jupiter class of planets.
HAT-P-27, also known as WASP-40, is the primary of a binary star system about 650 light-years away. It is a G-type main-sequence star. The star's age is similar to the Sun's at 4.4 billion years. HAT-P-27 is enriched in heavy elements, having a 195% concentration of iron compared to the Sun.
WASP-36 is a yellow main sequence star in the Hydra constellation.
WASP-78, is a single F-type main-sequence star about 2500 light-years away. It is likely to be younger than the Sun at 3.4+1.5
−0.8 billion years. WASP-78 is depleted in heavy elements, having a 45% concentration of iron compared to the Sun.
WASP-72 is the primary of a binary star system. It is an F7 class dwarf star, with an internal structure just on the verge of the Kraft break. It is orbited by a planet WASP-72b. The age of WASP-72 is younger than the Sun at 3.55±0.82 billion years.
WASP-52 is a K-type main-sequence star about 570 light-years away. It is older than the Sun at 10.7+1.9
−4.5 billion years, but it has a similar fraction of heavy elements. The star has prominent starspot activity, with 3% to 14% of the stellar surface covered by areas 575±150 K cooler than the rest of the photosphere.