Key parameters at a glance

A radius of 2.30 Earth radii
A mass of 5.89 Earth masses
Surface gravity around 1.12 g
An orbital period of 23.783 days
Semi-major axis 0.1625 AU
Equilibrium temperature 725 K (452 °C)
Distance from Earth 2,219.62 light-years
Earth Similarity Index 0.361
Travel time at Voyager 1 speed 39,143,033 years

1 sibling around Kepler-633

Kepler-633 c shares its host star with 1 other confirmed planet. Side-by-side measurements below.

Planet	Type	Radius (R⊕)	Mass (M⊕)	Period (d)	Eq. T (K)	Year
Kepler-633 b	Super-Earth	1.63	3.29	8.503	1,021	2016
Kepler-633 c this	Sub-Neptune	2.30	5.89	23.783	725	2021

Kepler-633 c Planet Profile

Physical Specs

Radius

2.30 R⊕

Radius (Jupiter)

0.205 R♃

Mass

5.89 M⊕

Mass (Jupiter)

0.019 M♃

Density

2.67 g/cm³

Surface Gravity

1.12 g (Earth)

Classification

Planet Type

Sub-Neptune

ESI Score 0.361

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

#1517of 1978

top 76.6%

This planet

2.30R⊕

Sub-Neptune median

2.71R⊕

Nearest-size peers

TOI-1669 c 2.30 R⊕ Kepler-1918 b 2.30 R⊕ K2-138 c 2.30 R⊕

Metric	Earth	Kepler-633 c	Jupiter
Radius (R⊕)	1.00	2.30	11.21
Mass (M⊕)	1.00	5.89	317.83
Density (g/cm³)	5.51	2.67	1.33
Surface Gravity (g)	1.00	1.12	2.53
Insolation (S⊕)	1.00	115.40	0.037

Star Catalogue Identifiers

TIC

TIC 138969239

System

Kepler-633

Percentile among Sub-Neptune cohort

Radius 2.296 R⊕ · percentile 23 / cohort 1978

Mass 5.890 M⊕ · percentile 23 / cohort 1978

Orbital period 23.78 d · percentile 67 / cohort 1946

Distance 680.54 pc · percentile 58 / cohort 1975

ESI 0.361 · percentile 43 / cohort 1978

Orbit & Habitability

Orbital Dynamics

Period

23.783 days

Semi-major axis

0.1625 AU

Eccentricity

0.000

Inclination

89.98 °

Year Length

A year here lasts approximately 23.78 Earth days (6.5% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.1625 AU.

Transit Fingerprint

Depth

0.026 %

Duration

7.939 h

Impact parameter b

0.783

Rp / R★

0.015940

Transit midpoint (BJD)

2,455,012.7501

Photometric dip

Transit produces a flux drop of 257 ppm lasting ≈ 7.94 h.

Extended Orbital Architecture

Planet / star radius ratio

0.015940

Semi-major axis / stellar radius

23.226

Impact parameter (b)

0.783

Transit mid-time (BJD)

2,455,012.7501

Angular separation (arcsec)

0.23900

Eq. Temperature

725K

(452 °C)

Insolation (S⊕)

115.40

Earth = 1.00

Earth Similarity (ESI)

0.361

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-633

Spectral Class

G-type yellow (Sun-like)

Effective Temperature

5,877 K — hotter than the Sun (5,778 K)

Estimated Age

8.13 Gyr — older than the Sun (4.6 Gyr)

Stellar Radius

1.265 R☉

Stellar Mass

0.997 M☉

Metallicity [Fe/H]

-0.04

Extended Stellar Properties

Surface gravity (log g)

4.233 dex

Stellar density

0.419 g/cm³

Metallicity ratio

[Fe/H]

Distance

680.54 parsec

Light-years 2,219.62 ly

V-band magnitude

13.81 mag

Voyager-speed travel 39,143,033 yr

Multi-band Host Photometry — 15 bands

Astrometric Data

Total Proper Motion

11.574 mas/yr

PM Right Ascension

-4.86 mas/yr

PM Declination

-10.50 mas/yr

Galactic Cartesian (pc)

x = 0.324 · y = -0.687 · z = 0.651

Equatorial (J2000)

RA 295.21733° · Dec 40.59216°

Galactic ℓ, b

74.299° · 8.746°

Ecliptic λ, β

311.049° · 60.487°

HTM-20 index

-1501632639