This page summarises the information held within TEPCat for the transiting planetary system Kepler-21. Please see here for descriptions of the quantities given below.
| Quantity | Value | Unit |
|---|---|---|
| Reference of discovery paper | 2012ApJ...746..123H | |
| Date of discovery paper | 2011 / 12 / 12 | y / m / d |
| Right ascension | 19 09 26.84 | h m s |
| Declination | +38 42 50.5 | d m s |
| V-band apparent magnitude | 8.25 | mag |
| K-band apparent magnitude | 6.95 | mag |
| Transit duration | 0.1496 ( 3.590 ) | day hour |
| Transit depth | 0.007 | % |
| Time of mid-transit | 2455093.83716 ± 0.00084 | HJD or BJD |
| Orbital period | 2.7858212 ± 0.0000032 | days |
| Reference for orbital ephemeris | 2016AJ....152..204L |
| Quantity | Value | Unit |
|---|---|---|
| Stellar effective temperature | 6305 ± 50 | K |
| Stellar metal abundance ([Fe/H] or [M/H]) | −0.03 ± 0.10 | dex |
| Stellar mass | 1.408 +0.021 −0.030 | Msun |
| Stellar radius | 1.902 +0.018 −0.012 | Rsun |
| Stellar logarithmic surface gravity | 4.026 ± 0.004 | c.g.s. |
| Stellar mean density | 0.203 +0.003 −0.004 ( 0.2864 +0.0042 −0.0056 ) | ρsun g cm-3 |
| Orbital eccentricity | 0.02 ± 0.1 | |
| Orbital semimajor axis | 0.04285 +0.00075 −0.00068 | AU |
| Planetary mass | 0.0160 ± 0.0054 ( 5.1 ± 1.7 ) | Mjup Mearth |
| Planetary radius | 0.1462 +0.0017 −0.0013 ( 1.639 +0.019 −0.015 ) | Rjup Rearth |
| Planetary surface gravity | m/s2 log(cgs) | |
| Planetary mean density | 4.8 ± 1.6 ( 6.4 ± 2.1 ) | ρjup g cm-3 |
| Planetary equilibrium temperature | 2025 ± 20 | K |
| Reference of detailed study | 2016AJ....152..204L |
Kepler-21 does not have an entry in the catalogue of Rossiter-McLaughlin measurements.
Kepler-21 has not been analysed as part of the Homogeneous Studies of Transiting Extrasolar Planets project.
Page generated on 2017/08/07 John Southworth (Keele University, UK)