Key parameters at a glance

A radius of 2.09 Earth radii
A mass of 5.00 Earth masses
Surface gravity around 1.15 g
An orbital period of 21.103 days
Semi-major axis 0.1533 AU
Equilibrium temperature 718 K (445 °C)
Distance from Earth 2,364.54 light-years
Earth Similarity Index 0.378
Travel time at Voyager 1 speed 41,698,597 years

Kepler-1823 b Planet Profile

Physical Specs

Radius

2.09 R⊕

Radius (Jupiter)

0.186 R♃

Mass

5.00 M⊕

Mass (Jupiter)

0.016 M♃

Density

3.03 g/cm³

Surface Gravity

1.15 g (Earth)

Classification

Planet Type

Sub-Neptune

ESI Score 0.378

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

#1844of 1978

top 93.2%

This planet

2.09R⊕

Sub-Neptune median

2.71R⊕

Nearest-size peers

TOI-2128 b 2.09 R⊕ Kepler-151 c 2.09 R⊕ Kepler-372 c 2.09 R⊕

Metric	Earth	Kepler-1823 b	Jupiter
Radius (R⊕)	1.00	2.09	11.21
Mass (M⊕)	1.00	5.00	317.83
Density (g/cm³)	5.51	3.03	1.33
Surface Gravity (g)	1.00	1.15	2.53
Insolation (S⊕)	1.00	78.00	0.037

Star Catalogue Identifiers

TIC

TIC 164559875

Gaia DR2

Gaia DR2 2106827216998206336

Gaia DR3

Gaia DR3 2106827216998206336

System

Kepler-1823

Percentile among Sub-Neptune cohort

Radius 2.086 R⊕ · percentile 7 / cohort 1978

Mass 5.000 M⊕ · percentile 8 / cohort 1978

Orbital period 21.10 d · percentile 64 / cohort 1946

Distance 724.97 pc · percentile 61 / cohort 1975

ESI 0.378 · percentile 48 / cohort 1978

Orbit & Habitability

Orbital Dynamics

Period

21.103 days

Semi-major axis

0.1533 AU

Eccentricity

0.000

Inclination

89.91 °

Year Length

A year here lasts approximately 21.10 Earth days (5.8% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.1533 AU.

Transit Fingerprint

Depth

0.019 %

Duration

2.005 h

Impact parameter b

0.063

Rp / R★

0.012851

Transit midpoint (BJD)

2,454,977.6609

Photometric dip

Transit produces a flux drop of 193 ppm lasting ≈ 2.00 h.

Extended Orbital Architecture

Planet / star radius ratio

0.012851

Semi-major axis / stellar radius

81.300

Impact parameter (b)

0.063

Transit mid-time (BJD)

2,454,977.6609

Angular separation (arcsec)

0.21100

Eq. Temperature

718K

(445 °C)

Insolation (S⊕)

78.00

Earth = 1.00

Earth Similarity (ESI)

0.378

0 = alien, 1 = Earth-identical

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

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-1823

Spectral Class

F-type yellow-white

Effective Temperature

6,000 K — hotter than the Sun (5,778 K)

Estimated Age

1.88 Gyr — younger than the Sun (4.6 Gyr)

Stellar Radius

1.126 R☉

Stellar Mass

1.068 M☉

Metallicity [Fe/H]

0.06

Extended Stellar Properties

Surface gravity (log g)

4.363 dex

Stellar density

20.699 g/cm³

Metallicity ratio

[Fe/H]

Distance

724.97 parsec

Light-years 2,364.54 ly

V-band magnitude

13.48 mag

Voyager-speed travel 41,698,597 yr

Multi-band Host Photometry — 16 bands

Astrometric Data

Parallax

1.351 mas

Total Proper Motion

9.249 mas/yr

PM Right Ascension

-0.82 mas/yr

PM Declination

-9.21 mas/yr

Galactic Cartesian (pc)

x = 0.167 · y = -0.683 · z = 0.711

Equatorial (J2000)

RA 283.75478° · Dec 45.33513°

Galactic ℓ, b

75.162° · 18.333°

Ecliptic λ, β

295.940° · 67.540°

HTM-20 index

514734924