This page summarises the information held within TEPCat for the transiting planetary system K2-21c. Please see here for descriptions of the quantities given below.
| Quantity | Value | Unit |
|---|---|---|
| Reference of discovery paper | 2015ApJ...811..102P | |
| Date of discovery paper | 2015 / 7 / 30 | y / m / d |
| Data/telescope used for discovery | K2 | |
| Right ascension | 22 41 12.89 | h m s |
| Declination | −14 29 20.4 | d m s |
| Right ascension (decimal) | 340.30371 | degrees |
| Declination (decimal) | -14.48900 | degrees |
| V-band apparent magnitude | 12.85 | mag |
| K-band apparent magnitude | 9.42 | mag |
| Transit duration | 0.096 ( 2.30 ) | day hour |
| Transit depth | 0.10 | % |
| Time of mid-transit | 2456988.4708 ± 0.0019 | HJD or BJD |
| Orbital period | 15.50120 ± 0.00096 | days |
| Reference for orbital ephemeris | 2015ApJ...811..102P |
| Quantity | Value | Unit |
|---|---|---|
| Stellar effective temperature | 4043 ± 375 | K |
| Stellar metal abundance ([Fe/H] or [M/H]) | −0.11 ± 0.13 | dex |
| Stellar mass | 0.64 ± 0.11 | Msun |
| Stellar radius | 0.60 ± 0.10 | Rsun |
| Stellar logarithmic surface gravity | c.g.s. | |
| Stellar mean density | ρsun g cm-3 | |
| Orbital eccentricity | ||
| Orbital semimajor axis | 0.1026 +0.0079 −0.0094 | AU |
| Planetary mass | 0.0122 +0.0038 −0.0034 ( 3.9 +1.2 −1.1 ) | Mjup Mearth |
| Planetary radius | 0.171 +0.048 −0.046 ( 1.92 +0.54 −0.52 ) | Rjup Rearth |
| Planetary surface gravity | m/s2 log(cgs) | |
| Planetary mean density | 1.41 +0.25 −0.33 ( 1.87 +0.33 −0.44 ) | ρjup g cm-3 |
| Planetary equilibrium temperature | 420 | K |
| Reference of detailed study | 2023MNRAS.520.4226M |
K2-21c does not have an entry in the catalogue of orbital obliquity measurements.
Page generated on 2026/01/29 John Southworth (Keele University, UK)