List_of_smallest_exoplanets
Below is a list of the smallest exoplanets so far discovered, in terms of physical size, ordered by radius.
This is a dynamic list and may never be able to satisfy particular standards for completeness. You can help by adding missing items with reliable sources.
The sizes are listed in units of Earth radii (R🜨). All planets listed are smaller than Earth and Venus, up to 0.7 Earth radii. The NASA Exoplanet Archive is used as the main data source.[1][2]
More information Exoplanet, Radius (R🜨) ...
| Exoplanet | Radius (R🜨) | Notes and references |
|---|---|---|
| SDSS J1228+1040 b (SDSS J122859.92+104033.0 b, WD 1226+110 b) |
0.010+0.0504 −0.0085[3][4] |
Extrasolar planetesimal. Likely a remnant iron core. Radius is in the range of 1.2 – 120 km.[3] |
| WD 1145+017 b | ~0.03[5] | Disintegrating planetesimal, likely one of several orbiting its star. Likely about one-tenth the mass of Ceres and ~200 km in radius.[5] |
| Ceres | 0.0742 | Shown for comparison |
| Pluto | 0.1863 | Shown for comparison |
| Moon | 0.2725 | Shown for comparison |
| Kepler-37b | 0.3098+0.0059 −0.0076 |
Smallest known exoplanet.[6][7] |
| PSR B1257+12 b (Draugr) | ~0.338 | Least massive known exoplanet, at 0.02 Earth masses. Radius estimated from mass-radius relationship.[8] |
| Kepler-1520b | ≲0.36 | Disintegrating planets with poorly known radii, all thought to be smaller than Mercury.[9][10] |
| KOI-2700b | ||
| K2-22b | ||
| Mercury | 0.3826 | Shown for comparison |
| Kepler-444b | 0.403+0.016 −0.014 |
[11] |
| Ganymede | 0.413 | Shown for comparison |
| Kepler-102b | 0.460±0.026 | [7] |
| Kepler-444c | 0.497+0.021 −0.017 |
[11] |
| Kepler-1971b (KOI-4777.01) | 0.51±0.03 | [12] |
| Kepler-1994b | 0.51+0.06 −0.05 |
[13] |
| Kepler-1308b | 0.52+0.06 −0.05 |
|
| Kepler-444d | 0.530+0.022 −0.019 |
[11] |
| Mars | 0.5325 | Shown for comparison |
| Kepler-62c | 0.54±0.03 | |
| Kepler-444e | 0.546+0.017 −0.015 |
[11] |
| Kepler-102c | 0.567±0.028 | [7] |
| Kepler-42d | 0.57±0.18 | |
| Kepler-1583b | 0.60+0.09 −0.05 |
|
| Kepler-1998b | 0.6+0.08 −0.04 |
[14] |
| Kepler-1087b | 0.61+0.17 −0.05 |
|
| K2-89b | 0.615±0.080 | |
| Kepler-1877b | 0.624 | |
| K2-137b | 0.64±0.10 | |
| Kepler-1371c | 0.64+0.07 −0.05 |
|
| Kepler-138b | 0.64±0.02 | [15] |
| Kepler-1130d | 0.645 | |
| Kepler-1351b | 0.65+0.05 −0.04 |
|
| Kepler-1542c | 0.65+0.09 −0.06 |
|
| Kepler-271d | 0.66±0.05 | |
| Kepler-431c | 0.668 | |
| Kepler-1558b | 0.68+0.06 −0.04 |
|
| LHS 1678 b | 0.685+0.037 −0.035 |
[16] |
| K2-116b | 0.69±0.04 | |
| Kepler-141b | 0.69±0.05 | |
| K2-297b (EPIC 201497682 b) | 0.692+0.059 −0.048 |
|
| Gliese 367 b (Tahay) | 0.699±0.024 | Smallest known exoplanet within 10 parsecs.[17] |
| Kepler-1349b | 0.700+0.630 −0.110 |
|
| Kepler-378c | 0.70±0.05 |
Close
Excluded objects
Kepler-37e is listed with a radius of 0.37±0.18 R🜨 in the Exoplanet Archive based on KOI data, but the existence of this planet is doubtful,[18] and assuming its existence, a 2023 study found a mass of 8.1±1.7 M🜨, inconsistent with such a small radius.[19]
KOI-6705.01, listed as a potential very small planet in the KOI dataset, was shown to be a false positive in 2016.[20]
TESS candidates
Below shows a list of TESS candidates below 0.7 R🜨 that have yet to be confirmed.
Kepler candidates
Below shows a list of Kepler candidates below 0.7 R🜨 that have yet to be confirmed.
More information Kepler object of interest, Radius (R🜨) ...
| Kepler object of interest | Radius (R🜨) | Notes and references |
|---|---|---|
| KOI-4582.01 | 0.35[22] | |
| KOI-2298.03 | 0.36[22] | |
| KOI-2169.04 | 0.37[22] | |
| KOI-7174.01 | 0.37[22] | |
| KOI-8012.01 | 0.42[22] | |
| KOI-6860.01 | 0.43[22] | |
| KOI-2059.02 | 0.44[22] | |
| KOI-304.02 | 0.46[22] | |
| KOI-7793.01 | 0.46[22] | |
| KOI-2678.02 | 0.48[22] | |
| KOI-6631.01 | 0.48[22] | |
| KOI-2421.02 | 0.48[22] | |
| KOI-5974.01 | 0.49[22] | |
| KOI-3444.03 | 0.5[22] | |
| KOI-2295.01 | 0.52[22] | |
| KOI-7863.01 | 0.52[22] | |
| KOI-2612.02 | 0.53[22] | |
| KOI-4657.01 | 0.54[22] | |
| KOI-8257.01 | 0.54[22] | |
| KOI-115.03 (Kepler-105d) | 0.55+0.08 −0.07 |
[23] |
| KOI-2421.01 | 0.55[22] | |
| KOI-4097.02 | 0.55[22] | |
| KOI-7645.01 | 0.55[22] | |
| KOI-3208.01 | 0.56[22] | |
| KOI-6763.01 | 0.56[22] | |
| KOI-2859.03 | 0.57[22] | |
| KOI-4146.02 | 0.57[22] | |
| KOI-2859.04 | 0.57[22] | |
| KOI-7873.01 | 0.57[22] | |
| KOI-2657.01 | 0.58[22] | |
| KOI-8277.01 | 0.58[22] | |
| KOI-4296.01 | 0.59[22] | |
| KOI-3196.01 | 0.59[22] | |
| KOI-5692.01 | 0.59[22] | |
| KOI-1964.01 | 0.6[22] | |
| KOI-4407.01 | 0.6[22] | |
| KOI-4871.01 | 0.6[22] | |
| KOI-5211.01 | 0.6[22] | |
| KOI-7888.01 | 0.6[22] | |
| KOI-3184.03 | 0.6[22] | |
| KOI-8183.01 | 0.6[22] | |
| KOI-3083.02 | 0.61[22] | |
| KOI-4421.01 | 0.61[22] | |
| KOI-4716.01 | 0.61[22] | |
| KOI-3102.01 | 0.61[22] | |
| KOI-7032.01 | 0.61[22] | |
| KOI-1843.03 | 0.61+0.12 −0.08 |
[24] |
| KOI-1499.02 | 0.62[22] | |
| KOI-605.02 | 0.62[22] | |
| KOI-7676.01 | 0.62[22] | |
| KOI-4849.01 | 0.62[22] | |
| KOI-365.02 | 0.62[22] | |
| KOI-7116.01 | 0.62[22] | |
| KOI-4421.02 | 0.62[22] | |
| KOI-7949.01 | 0.62[22] | |
| KOI-2029.04 | 0.63[22] | |
| KOI-6889.01 | 0.63[22] | |
| KOI-2636.02 | 0.63[22] | |
| KOI-3248.01 | 0.64[22] | |
| KOI-5213.01 | 0.64[22] | |
| KOI-6276.01 | 0.64[22] | |
| KOI-7617.01 | 0.64[22] | |
| KOI-7903.01 | 0.64[22] | |
| KOI-7925.01 | 0.64[22] | |
| KOI-8174.01 | 0.64[22] | |
| KOI-3083.03 | 0.65[22] | |
| KOI-4875.01 | 0.65[22] | |
| KOI-4808.01 | 0.65[22] | |
| KOI-6568.01 | 0.65[22] | |
| KOI-1619.01 | 0.66[22] | |
| KOI-3111.02 | 0.66[22] | |
| KOI-2859.05 | 0.66[22] | |
| KOI-3017.01 | 0.67[22] | |
| KOI-4907.01 | 0.67[22] | |
| KOI-1616.02 | 0.67[22] | |
| KOI-6299.01 | 0.67[22] | |
| KOI-8211.01 | 0.67[22] | |
| KOI-2593.02 | 0.68[22] | |
| KOI-4605.01 | 0.68[22] | |
| KOI-7832.01 | 0.68[22] | |
| KOI-7483.01 | 0.68[22] | |
| KOI-2623.02 | 0.68[22] | |
| KOI-7924.01 | 0.68[22] | |
| KOI-7628.01 | 0.69[22] | |
| KOI-4129.01 | 0.69[22] | |
| KOI-4822.01 | 0.69[22] | |
| KOI-6600.01 | 0.69[22] |
Close
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