This page summarises the information held within TEPCat for the transiting planetary system HAT-P-21. Please see here for descriptions of the quantities given below.
| Quantity | Value | Unit |
|---|---|---|
| Reference of discovery paper | 2011ApJ...742..116B | |
| Date of discovery paper | 2010 / 8 / 23 | y / m / d |
| Right ascension | 11 25 05.88 | h m s |
| Declination | +41 01 40.6 | d m s |
| V-band apparent magnitude | 11.69 | mag |
| K-band apparent magnitude | 10.11 | mag |
| Transit duration | 0.1530 ( 3.672 ) | day hour |
| Transit depth | 1.1 | % |
| Time of mid-transit | 2454996.41312 ± 0.00069 | HJD or BJD |
| Orbital period | 4.124481 ± 0.000007 | days |
| Reference for orbital ephemeris | 2011ApJ...742..116B |
| Quantity | Value | Unit |
|---|---|---|
| Stellar effective temperature | 5588 ± 80 | K |
| Stellar metal abundance ([Fe/H] or [M/H]) | +0.01 ± 0.08 | dex |
| Stellar mass | 0.947 ± 0.042 | Msun |
| Stellar radius | 1.105 ± 0.083 | Rsun |
| Stellar logarithmic surface gravity | 4.33 ± 0.06 | c.g.s. |
| Stellar mean density | ρsun g cm-3 | |
| Orbital eccentricity | 0.228 ± 0.016 | |
| Orbital semimajor axis | 0.0494 ± 0.0007 | AU |
| Planetary mass | 4.063 ± 0.161 ( 1291 ± 51 ) | Mjup Mearth |
| Planetary radius | 1.024 ± 0.092 ( 11.5 ± 1.0 ) | Rjup Rearth |
| Planetary surface gravity | 95 ± 18 3.98 ± 0.08 | m/s2 log(cgs) |
| Planetary mean density | 3.77 +1.28 −0.80 ( 5.0 +1.7 −1.1 ) | ρjup g cm-3 |
| Planetary equilibrium temperature | 1283 ± 50 | K |
| Reference of detailed study | 2011ApJ...742..116B |
HAT-P-21 does not have an entry in the catalogue of orbital obliquity measurements.
HAT-P-21 has not been analysed as part of the Homogeneous Studies of Transiting Extrasolar Planets project.
Page generated on 2021/01/04 John Southworth (Keele University, UK)