Key parameters at a glance

A radius of 0.94 Earth radii
A mass of 0.79 Earth masses
Surface gravity around 0.89 g
An orbital period of 2.187 days
Semi-major axis 0.0299 AU
Equilibrium temperature 1,099 K (826 °C)
Distance from Earth 1,503.25 light-years
Earth Similarity Index 0.287
Travel time at Voyager 1 speed 26,509,808 years
Almost certainly tidally locked to its host star given the close orbit

Kepler-1957 b Planet Profile

Physical Specs

Radius

0.94 R⊕

Radius (Jupiter)

0.084 R♃

Mass

0.79 M⊕

Mass (Jupiter)

0.002 M♃

Density

5.16 g/cm³

Surface Gravity

0.89 g (Earth)

Classification

Planet Type

Rocky Terrestrial

ESI Score 0.287

HZ Position Inner

Controversial No

Discovery

Year 2021

Method Transit

Facility Kepler

Telescope 0.95 m Kepler Telescope

Size rank in cohort

Rank by radius

#382of 570

top 66.8%

This planet

0.94R⊕

Rocky Terrestrial median

1.01R⊕

Nearest-size peers

LHS 1678 c 0.94 R⊕ Kepler-1689 b 0.95 R⊕ Kepler-1572 b 0.94 R⊕

Metric	Earth	Kepler-1957 b	Jupiter
Radius (R⊕)	1.00	0.94	11.21
Mass (M⊕)	1.00	0.79	317.83
Density (g/cm³)	5.51	5.16	1.33
Surface Gravity (g)	1.00	0.89	2.53
Insolation (S⊕)	1.00	345.07	0.037

Star Catalogue Identifiers

TIC

TIC 26961214

Gaia DR2

Gaia DR2 2128835110460415616

Gaia DR3

Gaia DR3 2128835110460415616

System

Kepler-1957

Percentile among Rocky Terrestrial cohort

Radius 0.944 R⊕ · percentile 33 / cohort 570

Mass 0.790 M⊕ · percentile 29 / cohort 570

Orbital period 2.19 d · percentile 24 / cohort 567

Distance 460.90 pc · percentile 60 / cohort 566

ESI 0.287 · percentile 35 / cohort 570

Orbit & Habitability

Orbital Dynamics

Period

2.187 days

Semi-major axis

0.0299 AU

Eccentricity

0.000

Inclination

82.31 °

Year Length

A year here lasts approximately 2.19 Earth days (0.6% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.0299 AU.

Transit Fingerprint

Depth

0.012 %

Duration

1.585 h

Impact parameter b

0.280

Rp / R★

0.009751

Transit midpoint (BJD)

2,454,964.9483

Photometric dip

Transit produces a flux drop of 118 ppm lasting ≈ 1.59 h.

Extended Orbital Architecture

Planet / star radius ratio

0.009751

Semi-major axis / stellar radius

6.190

Impact parameter (b)

0.280

Transit mid-time (BJD)

2,454,964.9483

Angular separation (arcsec)

0.06490

Eq. Temperature

1,099K

(826 °C)

Insolation (S⊕)

345.07

Earth = 1.00

Earth Similarity (ESI)

0.287

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

Valizadegan et al. 2022

Instrument

Kepler CCD Array

Publication

2022-02

Observation locale

Space

Discovery cohort

Planets confirmed in 2021 at Kepler (12 shown).

Kepler-1816 b · Super-Earth Kepler-1705 c · Sub-Neptune Kepler-1948 b · Rocky Terrestrial Kepler-196 d · Sub-Neptune Kepler-1853 b · Super-Earth Kepler-1840 b · Sub-Neptune Kepler-1881 b · Sub-Neptune Kepler-1858 b · Sub-Neptune Kepler-1874 b · Sub-Neptune Kepler-1802 c · Sub-Neptune Kepler-1749 b · Super-Earth Kepler-1849 b · Sub-Neptune

Host System: Kepler-1957

Spectral Class

K-type orange

Effective Temperature

4,904 K — cooler than the Sun (5,778 K)

Estimated Age

—

Stellar Radius

0.772 R☉

Stellar Mass

0.745 M☉

Metallicity [Fe/H]

0.00

Extended Stellar Properties

Surface gravity (log g)

4.535 dex

Stellar density

0.939 g/cm³

Metallicity ratio

[Fe/H]

Distance

460.90 parsec

Light-years 1,503.25 ly

V-band magnitude

15.13 mag

Voyager-speed travel 26,509,808 yr

Multi-band Host Photometry — 16 bands

Astrometric Data

Parallax

2.141 mas

Total Proper Motion

15.992 mas/yr

PM Right Ascension

9.08 mas/yr

PM Declination

-13.16 mas/yr

Galactic Cartesian (pc)

x = 0.270 · y = -0.614 · z = 0.742

Equatorial (J2000)

RA 293.71144° · Dec 47.88745°

Galactic ℓ, b

80.394° · 13.056°

Ecliptic λ, β

315.149° · 67.645°

HTM-20 index

-1764432310