Planet K2-18 b
| Name | K2-18 b | ||
| Planet Status | Confirmed | ||
| Discovered in | 2015 | ||
| Mass | 0.02807 ( -0.00503 +0.00535 ) MJ |  |
|
| Mass*sin(i) | — | |
|
| Semi-Major Axis | 0.1429 ( -0.0065 +0.006 ) AU | |
|
| Orbital Period | 32.939623 ( -0.0001 +9.5e-05 ) day | |
|
| Eccentricity | 0.2 (± 0.08) | |
|
| ω | -5.7 ( -33.8 +46.4 ) deg | |
|
| Tperi | — | ||
| Radius | 0.211 ( -0.02 +0.02 ) RJ | |
|
| Inclination | 89.5785 ( -0.0088 +0.0079 ) deg | ||
| Update | 2021-02-05 | ||
| Detection Method | Primary Transit | ||
| Mass Detection Method | Theoretical | ||
| Radius Detection Method | Primary Transit | ||
| Primary transit | 2457264.39144 (± 0.00065) JD | ||
| Secondary transit | — | ||
| λ | — | ||
| Impact Parameter b | — | ||
| Time Vr=0 | — | ||
| Velocity Semiamplitude K | 3.55 ( -0.58 +0.57 ) m/s | ||
| Calculated temperature | 284.0 ( -15.0 +15.0 ) K | |
|
| Measured temperature | — | ||
| Hottest point longitude | — | ||
| Geometric albedo | — | ||
| Surface gravity log(g/gH) | — | ||
| Alternate Names | EPIC 201912552 b, 2MASS J11301450+0735180 b, EPIC 201912552.01, WISE J113014.45+073516.8 b |
Star
K2-18| Name | K2-18 | ||
| Distance | 38.07 ( -0.08 +0.08 ) pc | ||
| Spectral type | M2.5 V | ||
| Apparent magnitude V | 13.5 | ||
| Mass | 0.36 ( -0.05 +0.05 ) MSun | ||
| Age | — | ||
| Effective temperature | 3457.0 ( -39.0 +39.0 ) K | ||
| Radius | 0.41 ( -0.04 +0.04 ) RSun | ||
| Metallicity [Fe/H] | 0.12 ( -0.16 +0.16 ) | ||
| Detected Disc | — | ||
| Magnetic Field | — | ||
| RA2000 | 11:30:14.5 | ||
| Dec2000 | +07:35:18 | ||
| Alternate Names | EPIC 201912552, 2MASS J11301450+0735180, WISE J113014.45+073516.8 | ||
| Planetary system | 2 planets |
Atmospheric parameters
Temperatures
| Data Source | Type | Result Value | Result Figure | Notes | Reference |
Molecules
| Molecule | Data Source | Type | Result Value | Result Figure | Notes | Reference |
| CH4 | Measurements | Detected | 2020 - MADHUSUDHAN N. | |||
| H2O | Measurements | Detected | 2020 - MADHUSUDHAN N. | |||
| Measurements | Detected | 2019 - BENNEKE B. | ||||
| Measurements | Detected | 2019 - TSIARAS A. | ||||
| NH3 | Measurements | Detected | 2020 - MADHUSUDHAN N. | |||
Observability Predictor 
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