Key parameters at a glance

A radius of 1.70 Earth radii
A mass of 3.53 Earth masses
Surface gravity around 1.22 g
An orbital period of 3.171 days
Semi-major axis 0.0415 AU
Equilibrium temperature 1,080 K (807 °C)
Distance from Earth 2,845.15 light-years
Earth Similarity Index 0.264
Travel time at Voyager 1 speed 50,174,219 years

Kepler-1138 b Planet Profile

Physical Specs

Radius

1.70 R⊕

Radius (Jupiter)

0.152 R♃

Mass

3.53 M⊕

Mass (Jupiter)

0.011 M♃

Density

3.95 g/cm³

Surface Gravity

1.22 g (Earth)

Classification

Planet Type

Super-Earth

ESI Score 0.264

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

#401of 1176

top 34.0%

This planet

1.70R⊕

Super-Earth median

1.60R⊕

Nearest-size peers

Kepler-341 c 1.70 R⊕ Kepler-1320 b 1.70 R⊕ Kepler-311 b 1.70 R⊕

Metric	Earth	Kepler-1138 b	Jupiter
Radius (R⊕)	1.00	1.70	11.21
Mass (M⊕)	1.00	3.53	317.83
Density (g/cm³)	5.51	3.95	1.33
Surface Gravity (g)	1.00	1.22	2.53
Insolation (S⊕)	1.00	245.90	0.037

Star Catalogue Identifiers

TIC

TIC 405685914

Gaia DR2

Gaia DR2 2131896494426821760

Gaia DR3

Gaia DR3 2131896494426821760

System

Kepler-1138

Percentile among Super-Earth cohort

Radius 1.700 R⊕ · percentile 65 / cohort 1176

Mass 3.530 M⊕ · percentile 59 / cohort 1176

Orbital period 3.17 d · percentile 23 / cohort 1164

Distance 872.33 pc · percentile 73 / cohort 1171

ESI 0.264 · percentile 28 / cohort 1176

Orbit & Habitability

Orbital Dynamics

Period

3.171 days

Semi-major axis

0.0415 AU

Eccentricity

0.000

Inclination

85.11 °

Year Length

A year here lasts approximately 3.17 Earth days (0.9% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.0415 AU.

Transit Fingerprint

Depth

0.033 %

Duration

1.578 h

Impact parameter b

0.029

Rp / R★

0.017125

Transit midpoint (BJD)

2,454,965.6773

Photometric dip

Transit produces a flux drop of 325 ppm lasting ≈ 1.58 h.

Extended Orbital Architecture

Planet / star radius ratio

0.017125

Semi-major axis / stellar radius

15.160

Impact parameter (b)

0.029

Transit mid-time (BJD)

2,454,965.6773

Angular separation (arcsec)

0.04760

Eq. Temperature

1,080K

(807 °C)

Insolation (S⊕)

245.90

Earth = 1.00

Earth Similarity (ESI)

0.264

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-1138

Spectral Class

G-type yellow (Sun-like)

Effective Temperature

5,582 K — cooler than the Sun (5,778 K)

Estimated Age

4.37 Gyr — younger than the Sun (4.6 Gyr)

Stellar Radius

0.920 R☉

Stellar Mass

0.950 M☉

Metallicity [Fe/H]

0.04

Extended Stellar Properties

Surface gravity (log g)

4.490 dex

Stellar density

6.553 g/cm³

Metallicity ratio

[Fe/H]

Distance

872.33 parsec

Light-years 2,845.15 ly

V-band magnitude

15.89 mag

Voyager-speed travel 50,174,219 yr

Multi-band Host Photometry — 16 bands

Astrometric Data

Parallax

1.118 mas

Total Proper Motion

10.648 mas/yr

PM Right Ascension

10.53 mas/yr

PM Declination

-1.61 mas/yr

Galactic Cartesian (pc)

x = 0.182 · y = -0.640 · z = 0.747

Equatorial (J2000)

RA 285.89932° · Dec 48.30729°

Galactic ℓ, b

78.633° · 18.005°

Ecliptic λ, β

302.149° · 69.978°

HTM-20 index

-34153955