Key parameters at a glance

A radius of 1.22 Earth radii
A mass of 1.96 Earth masses
Surface gravity around 1.33 g
An orbital period of 0.727 days
Semi-major axis 0.0115 AU
Equilibrium temperature 849 K (576 °C)
Earth Similarity Index 0.369
Almost certainly tidally locked to its host star given the close orbit

Kepler-1855 b Planet Profile

Physical Specs

Radius

1.22 R⊕

Radius (Jupiter)

0.109 R♃

Mass

1.96 M⊕

Mass (Jupiter)

0.006 M♃

Density

5.99 g/cm³

Surface Gravity

1.33 g (Earth)

Classification

Planet Type

Rocky Terrestrial

ESI Score 0.369

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

#51of 570

top 8.8%

This planet

1.22R⊕

Rocky Terrestrial median

1.01R⊕

Nearest-size peers

TOI-1776 b 1.22 R⊕ Kepler-1962 b 1.21 R⊕ K2-414 b 1.22 R⊕

Metric	Earth	Kepler-1855 b	Jupiter
Radius (R⊕)	1.00	1.22	11.21
Mass (M⊕)	1.00	1.96	317.83
Density (g/cm³)	5.51	5.99	1.33
Surface Gravity (g)	1.00	1.33	2.53
Insolation (S⊕)	1.00	86.97	0.037

Star Catalogue Identifiers

TIC

TIC 237189544

Gaia DR2

Gaia DR2 2104475013729123072

Gaia DR3

Gaia DR3 2104475013729123072

System

Kepler-1855

Percentile among Rocky Terrestrial cohort

Radius 1.216 R⊕ · percentile 91 / cohort 570

Mass 1.960 M⊕ · percentile 82 / cohort 570

Orbital period 0.73 d · percentile 6 / cohort 567

ESI 0.369 · percentile 54 / cohort 570

Orbit & Habitability

Orbital Dynamics

Period

0.727 days

Semi-major axis

0.0115 AU

Eccentricity

0.000

Inclination

88.70 °

Year Length

A year here lasts roughly 17.5 hours long on a nearly circular orbit at a mean orbital distance of 0.0115 AU.

Transit Fingerprint

Depth

0.040 %

Duration

0.933 h

Impact parameter b

0.153

Rp / R★

0.017336

Transit midpoint (BJD)

2,454,965.3709

Photometric dip

Transit produces a flux drop of 398 ppm lasting ≈ 0.93 h.

Extended Orbital Architecture

Planet / star radius ratio

0.017336

Semi-major axis / stellar radius

2.500

Impact parameter (b)

0.153

Transit mid-time (BJD)

2,454,965.3709

Eq. Temperature

849K

(576 °C)

Insolation (S⊕)

86.97

Earth = 1.00

Earth Similarity (ESI)

0.369

0 = alien, 1 = Earth-identical

Inside the inner HZ boundary (too hot for liquid water) — the surface is too hot to retain surface water. 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-1855

Spectral Class

M-type red dwarf

Effective Temperature

3,460 K — cooler than the Sun (5,778 K)

Estimated Age

5.85 Gyr — older than the Sun (4.6 Gyr)

Stellar Radius

0.356 R☉

Stellar Mass

0.385 M☉

Metallicity [Fe/H]

0.07

Extended Stellar Properties

Surface gravity (log g)

4.920 dex

Stellar density

10.956 g/cm³

Metallicity ratio

[Fe/H]

Multi-band Host Photometry — 16 bands

Astrometric Data

Total Proper Motion

37.686 mas/yr

PM Right Ascension

-13.05 mas/yr

PM Declination

-35.35 mas/yr

Galactic Cartesian (pc)

x = 0.174 · y = -0.728 · z = 0.663

Equatorial (J2000)

RA 283.40186° · Dec 41.51616°

Galactic ℓ, b

71.318° · 17.213°

Ecliptic λ, β

293.212° · 63.879°

HTM-20 index

1359061077