Key parameters at a glance

A radius of 6.51 Earth radii
A mass of 22.10 Earth masses
Surface gravity around 0.52 g
An orbital period of 10.502 days
Semi-major axis 0.1028 AU
Equilibrium temperature 1,378 K (1105 °C)
Distance from Earth 2,977.78 light-years
Earth Similarity Index 0.106
Travel time at Voyager 1 speed 52,513,230 years
Almost certainly tidally locked to its host star given the close orbit

2 siblings around Kepler-56

Kepler-56 b shares its host star with 2 other confirmed planets. Side-by-side measurements below.

Planet	Type	Radius (R⊕)	Mass (M⊕)	Period (d)	Eq. T (K)	Year
Kepler-56 b this	Neptune-like	6.51	22.10	10.502	1,378	2012
Kepler-56 c	Neptune-like	9.80	181.00	21.402	1,087	2012
Kepler-56 d	Gas Giant	12.80	1,784.00	1,002.000	—	2016

Kepler-56 b Planet Profile

Physical Specs

Radius

6.51 R⊕

Radius (Jupiter)

0.581 R♃

Mass

22.10 M⊕

Mass (Jupiter)

0.070 M♃

Density

0.44 g/cm³

Surface Gravity

0.52 g (Earth)

Classification

Planet Type

Neptune-like

ESI Score 0.106

HZ Position Inner

Controversial No

Discovery

Year 2012

Method Transit

Facility Kepler

Telescope 0.95 m Kepler Telescope

Size rank in cohort

Rank by radius

#239of 574

top 41.5%

This planet

6.51R⊕

Neptune-like median

6.39R⊕

Nearest-size peers

Kepler-603 c 6.50 R⊕ V1298 Tau d 6.53 R⊕ TOI-1052 c 6.48 R⊕

Metric	Earth	Kepler-56 b	Jupiter
Radius (R⊕)	1.00	6.51	11.21
Mass (M⊕)	1.00	22.10	317.83
Density (g/cm³)	5.51	0.44	1.33
Surface Gravity (g)	1.00	0.52	2.53
Insolation (S⊕)	1.00	819.25	0.037

Alternative Mass Estimates

Method	Value	Interpretation
Best measured mass	22.100 M⊕	Direct mass measurement (not derived).
Minimum mass (M sin i)	30.000 M⊕	Lower bound from radial-velocity fitting.

Star Catalogue Identifiers

TIC

TIC 138430034

Gaia DR2

Gaia DR2 2077617930392844800

Gaia DR3

Gaia DR3 2077617930392844800

System

Kepler-56

Percentile among Neptune-like cohort

Radius 6.510 R⊕ · percentile 58 / cohort 574

Mass 22.100 M⊕ · percentile 35 / cohort 574

Orbital period 10.50 d · percentile 38 / cohort 524

Distance 912.99 pc · percentile 71 / cohort 572

ESI 0.106 · percentile 4 / cohort 574

Orbit & Habitability

Orbital Dynamics

Period

10.502 days

Semi-major axis

0.1028 AU

Eccentricity

0.040

Inclination

89.66 °

Year Length

A year here lasts approximately 10.50 Earth days (2.9% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.1028 AU.

Transit Fingerprint

Depth

0.018 %

Duration

14.522 h

Impact parameter b

0.741

Rp / R★

0.011923

Transit midpoint (BJD)

2,454,978.2556

Photometric dip

Transit produces a flux drop of 183 ppm lasting ≈ 14.52 h.

Extended Orbital Architecture

Planet / star radius ratio

0.011923

Semi-major axis / stellar radius

5.617

Impact parameter (b)

0.741

RV semi-amplitude (K)

7.546 m/s

Transit mid-time (BJD)

2,454,978.2556

Long. of periastron (ω)

-11.00°

Angular separation (arcsec)

0.11300

Eq. Temperature

1,378K

(1105 °C)

Insolation (S⊕)

819.25

Earth = 1.00

Earth Similarity (ESI)

0.106

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.

Detection Signatures

Transit photometry

A transit dip has been observed from at least one telescope.

Transit timing variations

Gravitational interactions from neighbours have been detected.

Discovery Paper

Primary reference

Steffen et al. 2013

Instrument

Kepler CCD Array

Publication

2013-01

Observation locale

Space

Discovery cohort

Planets confirmed in 2012 at Kepler (12 shown).

Kepler-54 c · Rocky Terrestrial Kepler-49 c · Sub-Neptune Kepler-55 b · Sub-Neptune Kepler-49 b · Sub-Neptune Kepler-81 c · Sub-Neptune Kepler-55 c · Sub-Neptune Kepler-52 c · Super-Earth Kepler-83 c · Sub-Neptune Kepler-32 d · Sub-Neptune Kepler-83 b · Sub-Neptune Kepler-54 b · Sub-Neptune Kepler-80 c · Sub-Neptune

Host System: Kepler-56

Spectral Class

K-type orange

Effective Temperature

4,840 K — cooler than the Sun (5,778 K)

Estimated Age

3.50 Gyr — younger than the Sun (4.6 Gyr)

Stellar Radius

4.230 R☉

Stellar Mass

1.320 M☉

Metallicity [Fe/H]

0.20

Extended Stellar Properties

Surface gravity (log g)

3.310 dex

Stellar density

0.025 g/cm³

Systemic radial velocity

-54.30 km/s

Metallicity ratio

[Fe/H]

Distance

912.99 parsec

Light-years 2,977.78 ly

V-band magnitude

12.60 mag

Voyager-speed travel 52,513,230 yr

Multi-band Host Photometry — 16 bands

Astrometric Data

Parallax

1.067 mas

Total Proper Motion

13.788 mas/yr

PM Right Ascension

-6.75 mas/yr

PM Declination

-12.02 mas/yr

Galactic Cartesian (pc)

x = 0.300 · y = -0.682 · z = 0.667

Equatorial (J2000)

RA 293.75830° · Dec 41.87181°

Galactic ℓ, b

74.926° · 10.314°

Ecliptic λ, β

309.818° · 62.066°

HTM-20 index

-872674545

Similar Worlds

V1298 Tau d

Neptune-like · K-type orange

Radius 6.53 R⊕ · 352.9 ly

Kepler-1628 b

Neptune-like · K-type orange

Radius 6.43 R⊕ · 1,148.1 ly

CoRoT-8 b

Neptune-like · K-type orange

Radius 6.39 R⊕ · 1,050.3 ly

TOI-500 d

Neptune-like · K-type orange

Radius 6.35 R⊕ · 154.6 ly

HATS-7 b

Neptune-like · K-type orange

Radius 6.31 R⊕ · 785.1 ly

K2-45 b

Neptune-like · K-type orange

Radius 6.71 R⊕ · 1,615.5 ly

Explore Related Categories

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