Key parameters at a glance

A radius of 1.06 Earth radii
A mass of 1.20 Earth masses
Surface gravity around 1.07 g
An orbital period of 0.588 days
Semi-major axis 0.0114 AU
Equilibrium temperature 1,188 K (915 °C)
Distance from Earth 1,033.99 light-years
Earth Similarity Index 0.266
Travel time at Voyager 1 speed 18,234,347 years
Almost certainly tidally locked to its host star given the close orbit

Kepler-1203 b Planet Profile

Physical Specs

Radius

1.06 R⊕

Radius (Jupiter)

0.095 R♃

Mass

1.20 M⊕

Mass (Jupiter)

0.004 M♃

Density

5.54 g/cm³

Surface Gravity

1.07 g (Earth)

Classification

Planet Type

Rocky Terrestrial

ESI Score 0.266

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

#270of 570

top 47.2%

This planet

1.06R⊕

Rocky Terrestrial median

1.01R⊕

Nearest-size peers

Kepler-1200 b 1.06 R⊕ Kepler-1423 b 1.06 R⊕ Kepler-316 b 1.06 R⊕

Metric	Earth	Kepler-1203 b	Jupiter
Radius (R⊕)	1.00	1.06	11.21
Mass (M⊕)	1.00	1.20	317.83
Density (g/cm³)	5.51	5.54	1.33
Surface Gravity (g)	1.00	1.07	2.53
Insolation (S⊕)	1.00	723.81	0.037

Star Catalogue Identifiers

TIC

TIC 63449012

Gaia DR2

Gaia DR2 2126343823271448832

Gaia DR3

Gaia DR3 2126343823271448832

System

Kepler-1203

Percentile among Rocky Terrestrial cohort

Radius 1.060 R⊕ · percentile 51 / cohort 570

Mass 1.200 M⊕ · percentile 46 / cohort 570

Orbital period 0.59 d · percentile 4 / cohort 567

Distance 317.02 pc · percentile 42 / cohort 566

ESI 0.266 · percentile 29 / cohort 570

Orbit & Habitability

Orbital Dynamics

Period

0.588 days

Semi-major axis

0.0114 AU

Eccentricity

0.000

Inclination

83.78 °

Year Length

A year here lasts roughly 14.1 hours long on a nearly circular orbit at a mean orbital distance of 0.0114 AU.

Transit Fingerprint

Depth

0.030 %

Duration

1.163 h

Impact parameter b

0.790

Rp / R★

0.015575

Transit midpoint (BJD)

2,454,965.0591

Photometric dip

Transit produces a flux drop of 297 ppm lasting ≈ 1.16 h.

Extended Orbital Architecture

Planet / star radius ratio

0.015575

Semi-major axis / stellar radius

3.944

Impact parameter (b)

0.790

Transit mid-time (BJD)

2,454,965.0591

Angular separation (arcsec)

0.03600

Eq. Temperature

1,188K

(915 °C)

Insolation (S⊕)

723.81

Earth = 1.00

Earth Similarity (ESI)

0.266

0 = alien, 1 = Earth-identical

Inside the inner HZ boundary (too hot for liquid water) — the dayside is scorched. Close-orbiting tidally-locked around a cool host.

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-1203

Spectral Class

K-type orange

Effective Temperature

4,105 K — cooler than the Sun (5,778 K)

Estimated Age

3.47 Gyr — younger than the Sun (4.6 Gyr)

Stellar Radius

0.610 R☉

Stellar Mass

0.640 M☉

Metallicity [Fe/H]

0.01

Extended Stellar Properties

Surface gravity (log g)

4.670 dex

Stellar density

2.815 g/cm³

Metallicity ratio

[Fe/H]

Distance

317.02 parsec

Light-years 1,033.99 ly

V-band magnitude

15.39 mag

Voyager-speed travel 18,234,347 yr

Multi-band Host Photometry — 16 bands

Astrometric Data

Parallax

3.126 mas

Total Proper Motion

11.052 mas/yr

PM Right Ascension

11.04 mas/yr

PM Declination

-0.41 mas/yr

Galactic Cartesian (pc)

x = 0.278 · y = -0.661 · z = 0.697

Equatorial (J2000)

RA 292.77345° · Dec 44.17809°

Galactic ℓ, b

76.692° · 11.998°

Ecliptic λ, β

310.112° · 64.478°

HTM-20 index

-580489468