Key parameters at a glance

A radius of 3.15 Earth radii
A mass of 20.10 Earth masses
Surface gravity around 2.03 g
An orbital period of 18.262 days
Semi-major axis 0.1322 AU
Equilibrium temperature 728 K (455 °C)
Distance from Earth 253.36 light-years
Earth Similarity Index 0.346
Travel time at Voyager 1 speed 4,468,083 years

2 siblings around TOI-2141

TOI-2141 b shares its host star with 2 other confirmed planets. Side-by-side measurements below.

Planet	Type	Radius (R⊕)	Mass (M⊕)	Period (d)	Eq. T (K)	Year
TOI-2141 c	Sub-Neptune	2.35	6.14	5.462	1,095	2025
TOI-2141 b this	Sub-Neptune	3.15	20.10	18.262	728	2023
TOI-2141 d	Sub-Neptune	3.97	14.90	60.450	491	2025

TOI-2141 b Planet Profile

Physical Specs

Radius

3.15 R⊕

Radius (Jupiter)

0.281 R♃

Mass

20.10 M⊕

Mass (Jupiter)

0.063 M♃

Density

3.54 g/cm³

Surface Gravity

2.03 g (Earth)

Classification

Planet Type

Sub-Neptune

ESI Score 0.346

HZ Position Inner

Controversial No

Discovery

Year 2023

Method Transit

Facility Transiting Exoplanet Survey Satellite (TESS)

Telescope 0.1 m TESS Telescope

Size rank in cohort

Rank by radius

#397of 1978

top 20.0%

This planet

3.15R⊕

Sub-Neptune median

2.71R⊕

Nearest-size peers

Kepler-1790 b 3.14 R⊕ Kepler-1868 b 3.15 R⊕ Kepler-644 b 3.15 R⊕

Metric	Earth	TOI-2141 b	Jupiter
Radius (R⊕)	1.00	3.15	11.21
Mass (M⊕)	1.00	20.10	317.83
Density (g/cm³)	5.51	3.54	1.33
Surface Gravity (g)	1.00	2.03	2.53
Insolation (S⊕)	1.00	47.30	0.037

Alternative Mass Estimates

Method	Value	Interpretation
Best measured mass	20.100 M⊕	Direct mass measurement (not derived).
Minimum mass (M sin i)	20.100 M⊕	Lower bound from radial-velocity fitting.

Star Catalogue Identifiers

TIC

TIC 287256467

Gaia DR2

Gaia DR2 4548496986402688384

Gaia DR3

Gaia DR3 4548496986402688384

System

TOI-2141

Percentile among Sub-Neptune cohort

Radius 3.147 R⊕ · percentile 80 / cohort 1978

Mass 20.100 M⊕ · percentile 95 / cohort 1978

Orbital period 18.26 d · percentile 59 / cohort 1946

Distance 77.68 pc · percentile 17 / cohort 1975

ESI 0.346 · percentile 40 / cohort 1978

Orbit & Habitability

Orbital Dynamics

Period

18.262 days

Semi-major axis

0.1322 AU

Eccentricity

0.210

Inclination

88.76 °

Year Length

A year here lasts approximately 18.26 Earth days (5.0% of a terrestrial year) on a mildly elliptical path at a mean orbital distance of 0.1322 AU.

Transit Fingerprint

Depth

0.097 %

Duration

4.900 h

Impact parameter b

0.650

Rp / R★

0.030370

Transit midpoint (BJD)

2,458,992.5020

Photometric dip

Transit produces a flux drop of 971 ppm lasting ≈ 4.90 h.

Extended Orbital Architecture

Planet / star radius ratio

0.030370

Semi-major axis / stellar radius

29.930

Impact parameter (b)

0.650

RV semi-amplitude (K)

5.250 m/s

Transit mid-time (BJD)

2,458,992.5020

Long. of periastron (ω)

90.00°

Angular separation (arcsec)

1.70000

Eq. Temperature

728K

(455 °C)

Insolation (S⊕)

47.30

Earth = 1.00

Earth Similarity (ESI)

0.346

0 = alien, 1 = Earth-identical

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

Detection Signatures

Transit photometry

A transit dip has been observed from at least one telescope.

Radial velocity

Stellar wobble has been measured spectroscopically.

Discovery Paper

Primary reference

Martioli et al. 2023

Instrument

TESS CCD Array

Publication

2023-11

Observation locale

Space

Discovery cohort

Planets confirmed in 2023 at Transiting Exoplanet Survey Satellite (TESS) (12 shown).

TOI-700 e · Rocky Terrestrial TOI-2095 c · Super-Earth TOI-715 b · Super-Earth TOI-2095 b · Super-Earth TOI-2096 c · Super-Earth TOI-1680 b · Super-Earth TOI-2096 b · Rocky Terrestrial TOI-904 c · Sub-Neptune TOI-1470 c · Sub-Neptune TOI-198 b · Super-Earth TOI-244 b · Super-Earth TOI-4184 b · Sub-Neptune

Host System: TOI-2141

Spectral Class

G-type yellow (Sun-like)

Effective Temperature

5,635 K — cooler than the Sun (5,778 K)

Estimated Age

9.00 Gyr — older than the Sun (4.6 Gyr)

Stellar Radius

0.950 R☉

Stellar Mass

0.896 M☉

Metallicity [Fe/H]

-0.14

Extended Stellar Properties

Surface gravity (log g)

4.400 dex

Stellar density

1.521 g/cm³

Rotational v·sin i

2.70 km/s

Rotation period

21.00 days

Activity index (log R'HK)

-4.780

Metallicity ratio

[Fe/H]

Distance

77.68 parsec

Light-years 253.36 ly

V-band magnitude

9.46 mag

Voyager-speed travel 4,468,083 yr

Multi-band Host Photometry — 11 bands

Astrometric Data

Parallax

12.844 mas

Total Proper Motion

111.294 mas/yr

PM Right Ascension

52.12 mas/yr

PM Declination

-98.33 mas/yr

Galactic Cartesian (pc)

x = -0.185 · y = -0.931 · z = 0.315

Equatorial (J2000)

RA 258.76235° · Dec 18.34034°

Galactic ℓ, b

39.732° · 29.235°

Ecliptic λ, β

255.758° · 41.226°

HTM-20 index

206277409