Key parameters at a glance

A radius of 1.10 Earth radii
A mass of 1.37 Earth masses
Surface gravity around 1.13 g
An orbital period of 0.728 days
Equilibrium temperature 932 K (659 °C)
Distance from Earth 489.64 light-years
Earth Similarity Index 0.344
Travel time at Voyager 1 speed 8,634,773 years
Almost certainly tidally locked to its host star given the close orbit

EPIC 228836835 b Planet Profile

Physical Specs

Radius

1.10 R⊕

Radius (Jupiter)

0.098 R♃

Mass

1.37 M⊕

Mass (Jupiter)

0.004 M♃

Density

5.66 g/cm³

Surface Gravity

1.13 g (Earth)

Classification

Planet Type

Rocky Terrestrial

ESI Score 0.344

HZ Position Unknown

Controversial No

Discovery

Year 2021

Method Transit

Facility K2

Telescope 0.95 m Kepler Telescope

Size rank in cohort

Rank by radius

#224of 570

top 39.1%

This planet

1.10R⊕

Rocky Terrestrial median

1.01R⊕

Nearest-size peers

Kepler-392 c 1.10 R⊕ Kepler-59 b 1.10 R⊕ K2-239 d 1.10 R⊕

Metric	Earth	EPIC 228836835 b	Jupiter
Radius (R⊕)	1.00	1.10	11.21
Mass (M⊕)	1.00	1.37	317.83
Density (g/cm³)	5.51	5.66	1.33
Surface Gravity (g)	1.00	1.13	2.53
Insolation (S⊕)	1.00	—	0.037

Star Catalogue Identifiers

TIC

TIC 51641442

Gaia DR2

Gaia DR2 3680103286893920768

Gaia DR3

Gaia DR3 3680103286893920768

System

EPIC 228836835

Percentile among Rocky Terrestrial cohort

Radius 1.100 R⊕ · percentile 59 / cohort 570

Mass 1.370 M⊕ · percentile 54 / cohort 570

Orbital period 0.73 d · percentile 6 / cohort 567

Distance 150.12 pc · percentile 27 / cohort 566

ESI 0.344 · percentile 50 / cohort 570

Orbit & Habitability

Orbital Dynamics

Period

0.728 days

Semi-major axis

— AU

Eccentricity

—

Inclination

89.70 °

Year Length

A year here lasts roughly 17.5 hours long.

Transit Fingerprint

Depth

0.068 %

Duration

0.799 h

Impact parameter b

0.490

Rp / R★

0.029900

Transit midpoint (BJD)

2,457,585.4506

Photometric dip

Transit produces a flux drop of 680 ppm lasting ≈ 0.80 h.

Extended Orbital Architecture

Planet / star radius ratio

0.029900

Semi-major axis / stellar radius

6.400

Impact parameter (b)

0.490

Transit mid-time (BJD)

2,457,585.4506

Eq. Temperature

932K

(659 °C)

Insolation (S⊕)

—

Earth = 1.00

Earth Similarity (ESI)

0.344

0 = alien, 1 = Earth-identical

Insufficient insolation data — the surface is too hot to retain surface water. Close-orbiting tidally-locked around a cool host.

Discovery Paper

Primary reference

Adams et al. 2021

Instrument

Kepler CCD Array

Publication

2021-08

Observation locale

Space

Discovery cohort

Planets confirmed in 2021 at K2 (12 shown).

EPIC 220492298 b · Rocky Terrestrial EPIC 206042996 c · Rocky Terrestrial EPIC 212624936 b · Rocky Terrestrial EPIC 206024342 c · Super-Earth EPIC 201427007 b · Super-Earth K2-332 b · Sub-Neptune EPIC 212624936 c · Sub-Neptune EPIC 206024342 d · Sub-Neptune K2-345 b · Sub-Neptune K2-349 b · Super-Earth K2-343 c · Sub-Neptune K2-346 b · Sub-Neptune

Host System: EPIC 228836835

Spectral Class

K-type orange

Effective Temperature

3,782 K — cooler than the Sun (5,778 K)

Estimated Age

—

Stellar Radius

0.320 R☉

Stellar Mass

0.418 M☉

Metallicity [Fe/H]

-0.18

Extended Stellar Properties

Surface gravity (log g)

5.000 dex

Stellar density

7.740 g/cm³

Metallicity ratio

[Fe/H]

Distance

150.12 parsec

Light-years 489.64 ly

V-band magnitude

16.77 mag

Voyager-speed travel 8,634,773 yr

Multi-band Host Photometry — 11 bands

Astrometric Data

Parallax

6.634 mas

Total Proper Motion

108.758 mas/yr

PM Right Ascension

-108.24 mas/yr

PM Declination

10.66 mas/yr

Galactic Cartesian (pc)

x = -0.982 · y = -0.166 · z = -0.091

Equatorial (J2000)

RA 189.57490° · Dec -5.24462°

Galactic ℓ, b

296.841° · 57.472°

Ecliptic λ, β

190.853° · -1.030°

HTM-20 index

-1345830385