Key parameters at a glance

A radius of 1.19 Earth radii
A mass of 1.81 Earth masses
Surface gravity around 1.28 g
An orbital period of 0.813 days
Semi-major axis 0.0166 AU
Equilibrium temperature 1,693 K (1420 °C)
Distance from Earth 1,614.98 light-years
Earth Similarity Index 0.171
Travel time at Voyager 1 speed 28,480,188 years

Kepler-1139 b Planet Profile

Physical Specs

Radius

1.19 R⊕

Radius (Jupiter)

0.106 R♃

Mass

1.81 M⊕

Mass (Jupiter)

0.006 M♃

Density

5.90 g/cm³

Surface Gravity

1.28 g (Earth)

Classification

Planet Type

Rocky Terrestrial

ESI Score 0.171

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

#101of 570

top 17.5%

This planet

1.19R⊕

Rocky Terrestrial median

1.01R⊕

Nearest-size peers

KOI-351 c 1.19 R⊕ Kepler-953 c 1.19 R⊕ Kepler-310 b 1.19 R⊕

Metric	Earth	Kepler-1139 b	Jupiter
Radius (R⊕)	1.00	1.19	11.21
Mass (M⊕)	1.00	1.81	317.83
Density (g/cm³)	5.51	5.90	1.33
Surface Gravity (g)	1.00	1.28	2.53
Insolation (S⊕)	1.00	1,717.28	0.037

Star Catalogue Identifiers

TIC

TIC 121458495

Gaia DR2

Gaia DR2 2099735057762220288

Gaia DR3

Gaia DR3 2099735057762220288

System

Kepler-1139

Percentile among Rocky Terrestrial cohort

Radius 1.190 R⊕ · percentile 80 / cohort 570

Mass 1.810 M⊕ · percentile 74 / cohort 570

Orbital period 0.81 d · percentile 9 / cohort 567

Distance 495.16 pc · percentile 63 / cohort 566

ESI 0.171 · percentile 8 / cohort 570

Orbit & Habitability

Orbital Dynamics

Period

0.813 days

Semi-major axis

0.0166 AU

Eccentricity

0.000

Inclination

89.23 °

Year Length

A year here lasts roughly 19.5 hours long on a nearly circular orbit at a mean orbital distance of 0.0166 AU.

Transit Fingerprint

Depth

0.018 %

Duration

1.428 h

Impact parameter b

0.724

Rp / R★

0.012039

Transit midpoint (BJD)

2,454,964.8253

Photometric dip

Transit produces a flux drop of 178 ppm lasting ≈ 1.43 h.

Extended Orbital Architecture

Planet / star radius ratio

0.012039

Semi-major axis / stellar radius

4.482

Impact parameter (b)

0.724

Transit mid-time (BJD)

2,454,964.8253

Angular separation (arcsec)

0.03360

Eq. Temperature

1,693K

(1420 °C)

Insolation (S⊕)

1,717.28

Earth = 1.00

Earth Similarity (ESI)

0.171

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-1139

Spectral Class

G-type yellow (Sun-like)

Effective Temperature

5,550 K — cooler than the Sun (5,778 K)

Estimated Age

4.47 Gyr — younger than the Sun (4.6 Gyr)

Stellar Radius

0.910 R☉

Stellar Mass

0.940 M☉

Metallicity [Fe/H]

0.05

Extended Stellar Properties

Surface gravity (log g)

4.500 dex

Stellar density

1.650 g/cm³

Metallicity ratio

[Fe/H]

Distance

495.16 parsec

Light-years 1,614.98 ly

V-band magnitude

14.23 mag

Voyager-speed travel 28,480,188 yr

Multi-band Host Photometry — 17 bands

Astrometric Data

Parallax

1.991 mas

Total Proper Motion

6.918 mas/yr

PM Right Ascension

-2.54 mas/yr

PM Declination

-6.43 mas/yr

Galactic Cartesian (pc)

x = 0.239 · y = -0.737 · z = 0.632

Equatorial (J2000)

RA 287.94560° · Dec 39.23053°

Galactic ℓ, b

70.532° · 13.136°

Ecliptic λ, β

299.340° · 60.854°

HTM-20 index

-602346365