Key parameters at a glance

A radius of 0.79 Earth radii
A mass of 0.42 Earth masses
Surface gravity around 0.67 g
An orbital period of 1.917 days
Semi-major axis 0.0280 AU
Equilibrium temperature 1,246 K (973 °C)
Distance from Earth 1,354.26 light-years
Earth Similarity Index 0.237
Travel time at Voyager 1 speed 23,882,346 years

Kepler-1222 b Planet Profile

Physical Specs

Radius

0.79 R⊕

Radius (Jupiter)

0.070 R♃

Mass

0.42 M⊕

Mass (Jupiter)

0.001 M♃

Density

4.66 g/cm³

Surface Gravity

0.67 g (Earth)

Classification

Planet Type

Rocky Terrestrial

ESI Score 0.237

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

#488of 570

top 85.4%

This planet

0.79R⊕

Rocky Terrestrial median

1.01R⊕

Nearest-size peers

Kepler-1235 b 0.79 R⊕ Kepler-1566 b 0.79 R⊕ Kepler-390 c 0.79 R⊕

Metric	Earth	Kepler-1222 b	Jupiter
Radius (R⊕)	1.00	0.79	11.21
Mass (M⊕)	1.00	0.42	317.83
Density (g/cm³)	5.51	4.66	1.33
Surface Gravity (g)	1.00	0.67	2.53
Insolation (S⊕)	1.00	416.23	0.037

Star Catalogue Identifiers

TIC

TIC 27240404

Gaia DR2

Gaia DR2 2134837069559538176

Gaia DR3

Gaia DR3 2134837069559538176

System

Kepler-1222

Percentile among Rocky Terrestrial cohort

Radius 0.790 R⊕ · percentile 14 / cohort 570

Mass 0.418 M⊕ · percentile 12 / cohort 570

Orbital period 1.92 d · percentile 21 / cohort 567

Distance 415.22 pc · percentile 55 / cohort 566

ESI 0.237 · percentile 22 / cohort 570

Orbit & Habitability

Orbital Dynamics

Period

1.917 days

Semi-major axis

0.0280 AU

Eccentricity

0.000

Inclination

87.57 °

Year Length

A year here lasts approximately 1.92 Earth days (0.5% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.0280 AU.

Transit Fingerprint

Depth

0.011 %

Duration

1.463 h

Impact parameter b

0.173

Rp / R★

0.009377

Transit midpoint (BJD)

2,454,965.4670

Photometric dip

Transit produces a flux drop of 105 ppm lasting ≈ 1.46 h.

Extended Orbital Architecture

Planet / star radius ratio

0.009377

Semi-major axis / stellar radius

9.970

Impact parameter (b)

0.173

Transit mid-time (BJD)

2,454,965.4670

Angular separation (arcsec)

0.06750

Eq. Temperature

1,246K

(973 °C)

Insolation (S⊕)

416.23

Earth = 1.00

Earth Similarity (ESI)

0.237

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-1222

Spectral Class

G-type yellow (Sun-like)

Effective Temperature

5,239 K — cooler than the Sun (5,778 K)

Estimated Age

4.37 Gyr — younger than the Sun (4.6 Gyr)

Stellar Radius

0.800 R☉

Stellar Mass

0.840 M☉

Metallicity [Fe/H]

-0.04

Extended Stellar Properties

Surface gravity (log g)

4.560 dex

Stellar density

1.920 g/cm³

Metallicity ratio

[Fe/H]

Distance

415.22 parsec

Light-years 1,354.26 ly

V-band magnitude

14.21 mag

Voyager-speed travel 23,882,346 yr

Multi-band Host Photometry — 16 bands

Astrometric Data

Parallax

2.380 mas

Total Proper Motion

13.420 mas/yr

PM Right Ascension

-0.13 mas/yr

PM Declination

13.42 mas/yr

Galactic Cartesian (pc)

x = 0.274 · y = -0.591 · z = 0.759

Equatorial (J2000)

RA 294.88962° · Dec 49.37982°

Galactic ℓ, b

82.122° · 13.023°

Ecliptic λ, β

318.792° · 68.642°

HTM-20 index

-508184554