TEPCat: K2-18b


 

This page summarises the information held within TEPCat for the transiting planetary system K2-18b. Please see here for descriptions of the quantities given below.

 

Discovery and basic observable quantities:
 
Quantity Value Unit
Reference of discovery paper 2015ApJ...809...25M  
Date of discovery paper 2015 / 3 / 27 y / m / d
Right ascension 11 30 14.51 h m s
Declination +07 35 18.2 d m s
V-band apparent magnitude 13.50 mag
K-band apparent magnitude 8.899 mag
Transit duration 0.1110
( 2.664 )
day
hour
Transit depth 0.27 %
Time of mid-transit   2457264.39144 ± 0.00063     HJD or BJD
Orbital period 32.939614 ± 0.000093 days
Reference for orbital ephemeris   2017ApJ...834..187B  

 

Physical properties from the most recent detailed study:
 
Quantity Value Unit
Stellar effective temperature 3503 ± 60 K
Stellar metal abundance ([Fe/H] or [M/H])   +0.12 ± 0.16 dex
Stellar mass 0.495 ± 0.004   Msun
Stellar radius 0.469 ± 0.010 Rsun
Stellar logarithmic surface gravity c.g.s.
Stellar mean density ρsun
g cm-3
Orbital eccentricity 0.20 ± 0.08  
Orbital semimajor axis   0.1591 ± 0.0004  AU
Planetary mass 0.0271 ± 0.0042
( 8.6 ± 1.3 )
Mjup
Mearth
Planetary radius 0.242 ± 0.006
( 2.713 ± 0.067 )
Rjup
Rearth
Planetary surface gravity 11.5 ± 1.9
3.06 ± 0.07
m/s2
log(cgs)
Planetary mean density 1.8 ± 0.3
( 2.39 ± 0.40 )
ρjup
g cm-3
Planetary equilibrium temperature 265 ± 5 K
Reference of detailed study arXiv:1810.04731  

 

K2-18b does not have an entry in the catalogue of orbital obliquity measurements.

 

K2-18b has not been analysed as part of the Homogeneous Studies of Transiting Extrasolar Planets project.

 


Page generated on 2018/11/08           John Southworth   (Keele University, UK)