Key parameters at a glance

A radius of 1.83 Earth radii
A mass of 4.01 Earth masses
Surface gravity around 1.20 g
An orbital period of 6.080 days
Semi-major axis 0.0670 AU
Equilibrium temperature 1,111 K (838 °C)
Distance from Earth 3,232.90 light-years
Earth Similarity Index 0.250
Travel time at Voyager 1 speed 57,012,258 years

Kepler-638 b Planet Profile

Physical Specs

Radius

1.83 R⊕

Radius (Jupiter)

0.163 R♃

Mass

4.01 M⊕

Mass (Jupiter)

0.013 M♃

Density

3.60 g/cm³

Surface Gravity

1.20 g (Earth)

Classification

Planet Type

Super-Earth

ESI Score 0.250

HZ Position Inner

Controversial No

Discovery

Year 2016

Method Transit

Facility Kepler

Telescope 0.95 m Kepler Telescope

Size rank in cohort

Rank by radius

#221of 1176

top 18.7%

This planet

1.83R⊕

Super-Earth median

1.60R⊕

Nearest-size peers

WASP-47 e 1.83 R⊕ Kepler-110 b 1.83 R⊕ K2-316 c 1.83 R⊕

Metric	Earth	Kepler-638 b	Jupiter
Radius (R⊕)	1.00	1.83	11.21
Mass (M⊕)	1.00	4.01	317.83
Density (g/cm³)	5.51	3.60	1.33
Surface Gravity (g)	1.00	1.20	2.53
Insolation (S⊕)	1.00	872.57	0.037

Star Catalogue Identifiers

TIC

TIC 120420633

Gaia DR2

Gaia DR2 2104054832788419072

Gaia DR3

Gaia DR3 2104054832788419072

System

Kepler-638

Percentile among Super-Earth cohort

Radius 1.830 R⊕ · percentile 80 / cohort 1176

Mass 4.010 M⊕ · percentile 74 / cohort 1176

Orbital period 6.08 d · percentile 48 / cohort 1164

Distance 991.21 pc · percentile 80 / cohort 1171

ESI 0.250 · percentile 23 / cohort 1176

Orbit & Habitability

Orbital Dynamics

Period

6.080 days

Semi-major axis

0.0670 AU

Eccentricity

0.000

Inclination

85.43 °

Year Length

A year here lasts approximately 6.08 Earth days (1.7% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.0669 AU.

Transit Fingerprint

Depth

0.029 %

Duration

7.343 h

Impact parameter b

0.784

Rp / R★

0.018279

Transit midpoint (BJD)

2,455,003.5840

Photometric dip

Transit produces a flux drop of 290 ppm lasting ≈ 7.34 h.

Extended Orbital Architecture

Planet / star radius ratio

0.018279

Semi-major axis / stellar radius

4.300

Impact parameter (b)

0.784

Transit mid-time (BJD)

2,455,003.5840

Angular separation (arcsec)

0.06750

Eq. Temperature

1,111K

(838 °C)

Insolation (S⊕)

872.57

Earth = 1.00

Earth Similarity (ESI)

0.250

0 = alien, 1 = Earth-identical

Inside the inner HZ boundary (too hot for liquid water) — the dayside is scorched.

Discovery Paper

Primary reference

Morton et al. 2016

Instrument

Kepler CCD Array

Publication

2016-05

Observation locale

Space

Discovery cohort

Planets confirmed in 2016 at Kepler (12 shown).

Kepler-1512 b · Rocky Terrestrial Kepler-1410 b · Super-Earth Kepler-560 b · Super-Earth Kepler-1389 b · Super-Earth Kepler-1450 b · Super-Earth Kepler-1544 b · Super-Earth Kepler-1459 b · Super-Earth Kepler-1638 b · Super-Earth Kepler-737 b · Super-Earth Kepler-1185 b · Super-Earth Kepler-1178 b · Rocky Terrestrial Kepler-1040 b · Sub-Neptune

Host System: Kepler-638

Spectral Class

G-type yellow (Sun-like)

Effective Temperature

5,382 K — cooler than the Sun (5,778 K)

Estimated Age

11.75 Gyr — older than the Sun (4.6 Gyr)

Stellar Radius

0.930 R☉

Stellar Mass

0.880 M☉

Metallicity [Fe/H]

0.04

Extended Stellar Properties

Surface gravity (log g)

4.430 dex

Stellar density

0.110 g/cm³

Systemic radial velocity

-57.02 km/s

Metallicity ratio

[Fe/H]

Distance

991.21 parsec

Light-years 3,232.90 ly

V-band magnitude

13.66 mag

Voyager-speed travel 57,012,258 yr

Multi-band Host Photometry — 16 bands

Astrometric Data

Parallax

0.980 mas

Total Proper Motion

2.928 mas/yr

PM Right Ascension

2.56 mas/yr

PM Declination

1.42 mas/yr

Galactic Cartesian (pc)

x = 0.192 · y = -0.722 · z = 0.664

Equatorial (J2000)

RA 284.91942° · Dec 41.61721°

Galactic ℓ, b

71.855° · 16.196°

Ecliptic λ, β

295.771° · 63.728°

HTM-20 index

2102111877