Key parameters at a glance

A radius of 2.04 Earth radii
A mass of 4.82 Earth masses
Surface gravity around 1.16 g
An orbital period of 42.192 days
Semi-major axis 0.2315 AU
Equilibrium temperature 526 K (253 °C)
Distance from Earth 4,013.09 light-years
Earth Similarity Index 0.511
Travel time at Voyager 1 speed 70,770,814 years

Kepler-1122 b Planet Profile

Physical Specs

Radius

2.04 R⊕

Radius (Jupiter)

0.182 R♃

Mass

4.82 M⊕

Mass (Jupiter)

0.015 M♃

Density

3.12 g/cm³

Surface Gravity

1.16 g (Earth)

Classification

Planet Type

Sub-Neptune

ESI Score 0.511

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

#1904of 1978

top 96.2%

This planet

2.04R⊕

Sub-Neptune median

2.71R⊕

Nearest-size peers

TOI-2081 b 2.04 R⊕ Kepler-230 c 2.04 R⊕ Kepler-48 d 2.04 R⊕

Metric	Earth	Kepler-1122 b	Jupiter
Radius (R⊕)	1.00	2.04	11.21
Mass (M⊕)	1.00	4.82	317.83
Density (g/cm³)	5.51	3.12	1.33
Surface Gravity (g)	1.00	1.16	2.53
Insolation (S⊕)	1.00	23.26	0.037

Star Catalogue Identifiers

TIC

TIC 158664692

Gaia DR2

Gaia DR2 2130383394629702400

Gaia DR3

Gaia DR3 2130383394629702400

System

Kepler-1122

Percentile among Sub-Neptune cohort

Radius 2.040 R⊕ · percentile 3 / cohort 1978

Mass 4.820 M⊕ · percentile 5 / cohort 1978

Orbital period 42.19 d · percentile 82 / cohort 1946

Distance 1,230.42 pc · percentile 87 / cohort 1975

ESI 0.511 · percentile 72 / cohort 1978

Orbit & Habitability

Orbital Dynamics

Period

42.192 days

Semi-major axis

0.2315 AU

Eccentricity

0.000

Inclination

89.92 °

Year Length

A year here lasts approximately 42.19 Earth days (11.6% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.2315 AU.

Transit Fingerprint

Depth

0.049 %

Duration

7.108 h

Impact parameter b

0.733

Rp / R★

0.021429

Transit midpoint (BJD)

2,454,988.3155

Photometric dip

Transit produces a flux drop of 489 ppm lasting ≈ 7.11 h.

Extended Orbital Architecture

Planet / star radius ratio

0.021429

Semi-major axis / stellar radius

46.320

Impact parameter (b)

0.733

Transit mid-time (BJD)

2,454,988.3155

Angular separation (arcsec)

0.18800

Eq. Temperature

526K

(253 °C)

Insolation (S⊕)

23.26

Earth = 1.00

Earth Similarity (ESI)

0.511

0 = alien, 1 = Earth-identical

Inside the inner HZ boundary (too hot for liquid water) — the surface is too hot to retain surface water.

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-1122

Spectral Class

G-type yellow (Sun-like)

Effective Temperature

5,544 K — cooler than the Sun (5,778 K)

Estimated Age

4.68 Gyr — older than the Sun (4.6 Gyr)

Stellar Radius

0.890 R☉

Stellar Mass

0.920 M☉

Metallicity [Fe/H]

-0.03

Extended Stellar Properties

Surface gravity (log g)

4.510 dex

Stellar density

0.967 g/cm³

Metallicity ratio

[Fe/H]

Distance

1,230.42 parsec

Light-years 4,013.09 ly

V-band magnitude

15.41 mag

Voyager-speed travel 70,770,814 yr

Multi-band Host Photometry — 16 bands

Astrometric Data

Parallax

0.784 mas

Total Proper Motion

1.868 mas/yr

PM Right Ascension

1.83 mas/yr

PM Declination

0.37 mas/yr

Galactic Cartesian (pc)

x = 0.217 · y = -0.656 · z = 0.723

Equatorial (J2000)

RA 288.28058° · Dec 46.34087°

Galactic ℓ, b

77.357° · 15.774°

Ecliptic λ, β

304.617° · 67.595°

HTM-20 index

1735246196