TEPCat: K2-21b


 

This page summarises the information held within TEPCat for the transiting planetary system K2-21b. Please see here for descriptions of the quantities given below.

 

Discovery and basic observable quantities:
 
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 0.07 %
Time of mid-transit   2456989.4239 ± 0.0023     HJD or BJD
Orbital period 9.32414 ± 0.00061 days
Reference for orbital ephemeris   2015ApJ...811..102P  

 

Physical properties from the most recent detailed study:
 
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   0.0731 +0.0057 −0.0067  AU
Planetary mass 0.0050 +0.0016 −0.0014
( 1.59 +0.51 −0.45 )
Mjup
Mearth
Planetary radius 0.142 +0.037 −0.039
( 1.59 +0.41 −0.44 )
Rjup
Rearth
Planetary surface gravity m/s2
log(cgs)
Planetary mean density 0.91 +0.21 −0.170
( 1.21 +0.28 −0.23 )
ρjup
g cm-3
Planetary equilibrium temperature 500 K
Reference of detailed study 2023MNRAS.520.4226M  

 

K2-21b does not have an entry in the catalogue of orbital obliquity measurements.

 


Page generated on 2024/11/01           John Southworth   (Keele University, UK)