This page summarises the information held within TEPCat for the transiting planetary system K2-139. Please see here for descriptions of the quantities given below.
| Quantity | Value | Unit |
|---|---|---|
| Reference of discovery paper | 2018MNRAS.475.1765B | |
| Date of discovery paper | 2017 / 2 / 3 | y / m / d |
| Data/telescope used for discovery | K2 | |
| Right ascension | 19 16 15.97 | h m s |
| Declination | −17 54 38.5 | d m s |
| Right ascension (decimal) | 289.06654 | degrees |
| Declination (decimal) | -17.91069 | degrees |
| V-band apparent magnitude | 11.65 | mag |
| K-band apparent magnitude | 9.66 | mag |
| Transit duration | 0.204 ( 4.90 ) | day hour |
| Transit depth | 1.1 | % |
| Time of mid-transit | 2459057.16689 ± 0.00083 | HJD or BJD |
| Orbital period | 28.382796 ± 0.000042 | days |
| Reference for orbital ephemeris | 2022AJ....164...21S |
| Quantity | Value | Unit |
|---|---|---|
| Stellar effective temperature | 5245 +73 −33 | K |
| Stellar metal abundance ([Fe/H] or [M/H]) | +0.22 ± 0.08 | dex |
| Stellar mass | 0.883 +0.021 −0.029 | Msun |
| Stellar radius | 0.863 +0.019 −0.014 | Rsun |
| Stellar logarithmic surface gravity | 4.53 ± 0.05 | c.g.s. |
| Stellar mean density | 1.37 ± 0.09 ( 1.93 ± 0.13 ) | ρsun g cm-3 |
| Orbital eccentricity | 0.12 +0.12 −0.08 | |
| Orbital semimajor axis | 0.179 +0.029 −0.027 | AU |
| Planetary mass | 0.382 ± 0.078 ( 121 ± 24 ) | Mjup Mearth |
| Planetary radius | 0.803 +0.024 −0.023 ( 9.00 +0.27 −0.26 ) | Rjup Rearth |
| Planetary surface gravity | m/s2 log(cgs) | |
| Planetary mean density | 0.69 +0.16 −0.15 ( 0.92 +0.21 −0.20 ) | ρjup g cm-3 |
| Planetary equilibrium temperature | 536 +11 −8 | K |
| Reference of detailed study | 2022AJ....164...21S |
| Reference | λ (degrees) |
|---|---|
| Prinoth et al. (2024) | −17 ± 7 |
| Espinoza-Retamal et al. (2025) | −14.5 + 2.5 - 2.8 |
Page generated on 2025/03/24 John Southworth (Keele University, UK)