Key parameters at a glance

A radius of 2.93 Earth radii
A mass of 8.92 Earth masses
Surface gravity around 1.04 g
An orbital period of 10.284 days
Semi-major axis 0.0930 AU
Equilibrium temperature 780 K (507 °C)
Distance from Earth 548.75 light-years
Earth Similarity Index 0.305
Travel time at Voyager 1 speed 9,677,222 years

TOI-4638.01 Planet Profile

Physical Specs

Radius

2.93 R⊕

Radius (Jupiter)

0.262 R♃

Mass

8.92 M⊕

Mass (Jupiter)

0.028 M♃

Density

1.94 g/cm³

Surface Gravity

1.04 g (Earth)

Classification

Planet Type

Sub-Neptune

ESI Score 0.305

HZ Position Inner

Controversial No

Discovery

Year 2024

Method Transit

Facility Transiting Exoplanet Survey Satellite (TESS)

Telescope 0.1 m TESS Telescope

Size rank in cohort

Rank by radius

#583of 1978

top 29.4%

This planet

2.93R⊕

Sub-Neptune median

2.71R⊕

Nearest-size peers

Kepler-1731 b 2.93 R⊕ Kepler-1673 b 2.94 R⊕ TOI-125 d 2.93 R⊕

Metric	Earth	TOI-4638.01	Jupiter
Radius (R⊕)	1.00	2.93	11.21
Mass (M⊕)	1.00	8.92	317.83
Density (g/cm³)	5.51	1.94	1.33
Surface Gravity (g)	1.00	1.04	2.53
Insolation (S⊕)	1.00	87.81	0.037

Star Catalogue Identifiers

TIC

TIC 58824746

Gaia DR2

Gaia DR2 2775311010868306048

Gaia DR3

Gaia DR3 2775311010868306048

System

TOI-4638

Percentile among Sub-Neptune cohort

Radius 2.933 R⊕ · percentile 71 / cohort 1978

Mass 8.920 M⊕ · percentile 64 / cohort 1978

Orbital period 10.28 d · percentile 35 / cohort 1946

Distance 168.25 pc · percentile 27 / cohort 1975

ESI 0.305 · percentile 29 / cohort 1978

Orbit & Habitability

Orbital Dynamics

Period

10.284 days

Semi-major axis

0.0930 AU

Eccentricity

—

Inclination

— °

Year Length

A year here lasts approximately 10.28 Earth days (2.8% of a terrestrial year) at a mean orbital distance of 0.0930 AU.

Transit Fingerprint

Depth

0.087 %

Duration

3.723 h

Rp / R★

0.029900

Transit midpoint (BJD)

2,459,449.3508

Photometric dip

Transit produces a flux drop of 865 ppm lasting ≈ 3.72 h.

Eq. Temperature

780K

(507 °C)

Insolation (S⊕)

87.81

Earth = 1.00

Earth Similarity (ESI)

0.305

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

Crossfield et al. 2024

Instrument

TESS CCD Array

Publication

2024-11

Observation locale

Space

Discovery cohort

Planets confirmed in 2024 at Transiting Exoplanet Survey Satellite (TESS) (12 shown).

Gliese 12 b · Rocky Terrestrial TOI-6002 b · Super-Earth TOI-5713 b · Super-Earth TOI-4336 A b · Sub-Neptune TOI-406.01 · Sub-Neptune TOI-1224 c · Sub-Neptune LHS 1678 d · Rocky Terrestrial TOI-2088 b · Sub-Neptune TOI-2120 b · Sub-Neptune TOI-1806.01 · Sub-Neptune TOI-4633 c · Sub-Neptune TOI-260 b · Super-Earth

Host System: TOI-4638

Spectral Class

G-type yellow (Sun-like)

Effective Temperature

5,700 K — cooler than the Sun (5,778 K)

Estimated Age

—

Stellar Radius

0.895 R☉

Stellar Mass

1.020 M☉

Metallicity [Fe/H]

—

Distance

168.25 parsec

Light-years 548.75 ly

V-band magnitude

11.66 mag

Voyager-speed travel 9,677,222 yr

Multi-band Host Photometry — 16 bands

Astrometric Data

Parallax

5.916 mas

Total Proper Motion

14.340 mas/yr

PM Right Ascension

5.34 mas/yr

PM Declination

-13.31 mas/yr

Galactic Cartesian (pc)

x = 0.951 · y = 0.216 · z = 0.221

Equatorial (J2000)

RA 12.82066° · Dec 12.78799°

Galactic ℓ, b

122.873° · -50.084°

Ecliptic λ, β

16.768° · 6.719°

HTM-20 index

1053049480