TEPCat: K2-138b


 

This page summarises the information held within TEPCat for the transiting planetary system K2-138b. Please see here for descriptions of the quantities given below.

 

Discovery and basic observable quantities:
 
Quantity Value Unit
Reference of discovery paper 2018AJ....155...57C  
Date of discovery paper 2018 / 1 / 12 y / m / d
Right ascension 23 15 47.77 h m s
Declination −10 50 58.9 d m s
V-band apparent magnitude 12.21 mag
K-band apparent magnitude 10.31 mag
Transit duration 0.0721
( 1.730 )
day
hour
Transit depth 0.03 %
Time of mid-transit   2457773.31683 ± 0.00091     HJD or BJD
Orbital period 2.35309 ± 0.00022 days
Reference for orbital ephemeris   arXiv:1909.13527  

 

Physical properties from the most recent detailed study:
 
Quantity Value Unit
Stellar effective temperature 5350 ± 80 K
Stellar metal abundance ([Fe/H] or [M/H])   +0.14 ± 0.10 dex
Stellar mass 0.93 ± 0.02   Msun
Stellar radius 0.86 +0.03 −0.02 Rsun
Stellar logarithmic surface gravity 4.54 +0.02 −0.04 c.g.s.
Stellar mean density 1.46 +0.10 −0.19
( 2.06 +0.14 −0.27 )
ρsun
g cm-3
Orbital eccentricity 0.0 +0.189 −0.0  
Orbital semimajor axis   0.03385 +0.00023 −0.00029  AU
Planetary mass 0.0098 ± 0.0035
( 3.1 ± 1.1 )
Mjup
Mearth
Planetary radius 0.135 +0.010 −0.007
( 1.513 +0.112 −0.078 )
Rjup
Rearth
Planetary surface gravity m/s2
log(cgs)
Planetary mean density 3.7 +1.5 −1.3
( 4.9 +2.0 −1.7 )
ρjup
g cm-3
Planetary equilibrium temperature 1308 +24 −20 K
Reference of detailed study arXiv:1909.13527  

 

K2-138b does not have an entry in the catalogue of orbital obliquity measurements.

 

K2-138b 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)