Discovery Method
Transit
Consistent across records
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ExoplanetDetail
K2-18 b
Host star K2-18 • 2.37 R⊕ • 32.94 d orbit
Records
11
archive rows
Discovery
2015
Transit
Radius
2.37 R⊕
default parameter set
Mass
8.92 M⊕
default parameter set
K2-18
284 K equilibrium
Canonical Summary
Adopted planet values from the default parameter set
Values come from the archive's default parameter set. Missing values stay missing. Ranges and counts describe all source rows.
Selected source: Sarkis et al. 2018
Host Star
K2-18
Stable across source rows
Discovery Year
2015
Stable across source rows
Orbital Period
32.94 day
32.93 to 32.95
Semi-Major Axis
0.14 au
0.14 to 0.16
Radius
2.37 Rearth
1.40 to 2.61
Mass
8.92 Mearth
7.20 to 8.92
Density
4.11 g/cm**3
2.28 to 4.11
Equilibrium Temperature
284 K
235 to 284
Scale Comparison
Radius against familiar reference worlds
Current adopted radius: 2.37 R⊕ • circles scaled linearly by radius
Earth
1.0 R⊕ baseline
K2-18 b
2.37 R⊕
Jupiter
11.2 R⊕ reference
Provenance
Underlying measurements and references
Evidence Summary
Rows
11
Refs
11
Methods
1
Discoverystable
Facilitystable
Perioddisputed
Radiusdisputed
Massdisputed
Eq. Tempdisputed
| Year | Method | Facility | Telescope | Period | Radius | Mass | Eq. Temp | Reference |
|---|---|---|---|---|---|---|---|---|
| 2015 | Transit | K2 | 0.95 m Kepler Telescope | 32.95 day | 2.17 Rearth | — | — | Vanderburg et al. 2016 |
| 2015 | Transit | K2 | 0.95 m Kepler Telescope | 32.94 day | 2.24 Rearth | — | 272 K | Montet et al. 2015 |
| 2015 | Transit | K2 | 0.95 m Kepler Telescope | 32.94 day | 1.40 Rearth | — | — | Kruse et al. 2019 |
| 2015 | Transit | K2 | 0.95 m Kepler Telescope | 32.94 day | 2.61 Rearth | 8.63 Mearth | 254.9 K | Benneke et al. 2019 |
| 2015 | Transit | K2 | 0.95 m Kepler Telescope | 32.94 day | 2.53 Rearth | — | 260.4 K | ExoFOP |
| 2015 | Transit | K2 | 0.95 m Kepler Telescope | 32.94 day | 2.46 Rearth | 7.20 Mearth | 281 K | Howard et al. 2025 |
| 2015 | Transit | K2 | 0.95 m Kepler Telescope | 32.94 day | 2.28 Rearth | — | — | Crossfield et al. 2016 |
| 2015 | Transit | K2 | 0.95 m Kepler Telescope | 32.93 day | — | — | — | Barros et al. 2016 |
| 2015 | Transit | K2 | 0.95 m Kepler Telescope | 32.94 day | 2.38 Rearth | 7.96 Mearth | 235 K | Cloutier et al. 2017 |
| 2015 | Transit | K2 | 0.95 m Kepler Telescope | 32.94 day | 2.28 Rearth | — | — | Benneke et al. 2017 |
| 2015 | Transit | K2 | 0.95 m Kepler Telescope | 32.94 day | 2.37 Rearth | 8.92 Mearth | 284 K | Sarkis et al. 2018 |