Key parameters at a glance

A radius of 4.26 Earth radii
A mass of 16.80 Earth masses
Surface gravity around 0.93 g
An orbital period of 2.703 days
Semi-major axis 0.0330 AU
Equilibrium temperature 705 K (432 °C)
Distance from Earth 301.49 light-years
Earth Similarity Index 0.288
Travel time at Voyager 1 speed 5,316,732 years
Almost certainly tidally locked to its host star given the close orbit

TOI-2407 b Planet Profile

Physical Specs

Radius

4.26 R⊕

Radius (Jupiter)

0.380 R♃

Mass

16.80 M⊕

Mass (Jupiter)

0.053 M♃

Density

1.19 g/cm³

Surface Gravity

0.93 g (Earth)

Classification

Planet Type

Neptune-like

ESI Score 0.288

HZ Position Inner

Controversial No

Discovery

Year 2025

Method Transit

Facility Transiting Exoplanet Survey Satellite (TESS)

Telescope 0.1 m TESS Telescope

Size rank in cohort

Rank by radius

#506of 574

top 88.0%

This planet

4.26R⊕

Neptune-like median

6.39R⊕

Nearest-size peers

HD 34445 e 4.26 R⊕ DMPP-1 b 4.26 R⊕ Kepler-230 b 4.26 R⊕

Metric	Earth	TOI-2407 b	Jupiter
Radius (R⊕)	1.00	4.26	11.21
Mass (M⊕)	1.00	16.80	317.83
Density (g/cm³)	5.51	1.19	1.33
Surface Gravity (g)	1.00	0.93	2.53
Insolation (S⊕)	1.00	41.00	0.037

Star Catalogue Identifiers

TIC

TIC 153078576

Gaia DR2

Gaia DR2 4847001302277419904

Gaia DR3

Gaia DR3 4847001302277419904

System

TOI-2407

Percentile among Neptune-like cohort

Radius 4.260 R⊕ · percentile 11 / cohort 574

Mass 16.800 M⊕ · percentile 16 / cohort 574

Orbital period 2.70 d · percentile 3 / cohort 524

Distance 92.44 pc · percentile 23 / cohort 572

ESI 0.288 · percentile 47 / cohort 574

Orbit & Habitability

Orbital Dynamics

Period

2.703 days

Semi-major axis

0.0330 AU

Eccentricity

0.080

Inclination

88.83 °

Year Length

A year here lasts approximately 2.70 Earth days (0.7% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.0330 AU.

Transit Fingerprint

Depth

0.513 %

Duration

1.700 h

Impact parameter b

0.250

Rp / R★

0.068900

Transit midpoint (BJD)

2,459,149.0561

Photometric dip

Transit produces a flux drop of 5,133 ppm lasting ≈ 1.70 h.

Extended Orbital Architecture

Planet / star radius ratio

0.068900

Impact parameter (b)

0.250

Transit mid-time (BJD)

2,459,149.0561

Long. of periastron (ω)

42.00°

Angular separation (arcsec)

0.35700

Eq. Temperature

705K

(432 °C)

Insolation (S⊕)

41.00

Earth = 1.00

Earth Similarity (ESI)

0.288

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

Jan & Oacute Mu & Ntilde Oz et al. 2025

Instrument

TESS CCD Array

Publication

2025-06

Observation locale

Space

Discovery cohort

Planets confirmed in 2025 at Transiting Exoplanet Survey Satellite (TESS) (12 shown).

TOI-1266 d · Super-Earth TOI-2267 c · Rocky Terrestrial TOI-5799 c · Super-Earth TOI-5728 b · Super-Earth TOI-5716 b · Rocky Terrestrial TOI-7166 b · Sub-Neptune TOI-2267 b · Rocky Terrestrial TOI-2093 c · Sub-Neptune TOI-2267 d · Super-Earth TOI-5489 c · Super-Earth TOI-1743 b · Super-Earth TOI-4364 b · Sub-Neptune

Host System: TOI-2407

Spectral Class

M-type red dwarf

Effective Temperature

3,530 K — cooler than the Sun (5,778 K)

Estimated Age

—

Stellar Radius

0.567 R☉

Stellar Mass

0.548 M☉

Metallicity [Fe/H]

0.21

Extended Stellar Properties

Surface gravity (log g)

4.716 dex

Stellar density

4.850 g/cm³

Metallicity ratio

[Fe/H]

Distance

92.44 parsec

Light-years 301.49 ly

V-band magnitude

14.68 mag

Voyager-speed travel 5,316,732 yr

Multi-band Host Photometry — 11 bands

Astrometric Data

Parallax

10.789 mas

Total Proper Motion

98.809 mas/yr

PM Right Ascension

10.82 mas/yr

PM Declination

-98.21 mas/yr

Galactic Cartesian (pc)

x = 0.445 · y = 0.526 · z = -0.725

Equatorial (J2000)

RA 49.74655° · Dec -46.45803°

Galactic ℓ, b

256.540° · -55.175°

Ecliptic λ, β

23.548° · -60.949°

HTM-20 index

-2029330738