Key parameters at a glance

A radius of 23.54 Earth radii
A mass of 375.04 Earth masses
Surface gravity around 0.68 g
An orbital period of 3.120 days
Semi-major axis 0.0429 AU
Equilibrium temperature 1,498 K (1225 °C)
Earth Similarity Index 0.045

TOI-3540 A b Planet Profile

Physical Specs

Radius

23.54 R⊕

Radius (Jupiter)

2.100 R♃

Mass

375.04 M⊕

Mass (Jupiter)

1.180 M♃

Density

0.07 g/cm³

Surface Gravity

0.68 g (Earth)

Classification

Planet Type

Gas Giant

ESI Score 0.045

HZ Position Inner

Controversial No

Discovery

Year 2022

Method Transit

Facility Transiting Exoplanet Survey Satellite (TESS)

Telescope 0.1 m TESS Telescope

Size rank in cohort

Rank by radius

#9of 1771

top 0.5%

This planet

23.54R⊕

Gas Giant median

13.52R⊕

Nearest-size peers

XO-6 b 23.20 R⊕ HAT-P-67 b 23.99 R⊕ HAT-P-41 b 22.98 R⊕

Metric	Earth	TOI-3540 A b	Jupiter
Radius (R⊕)	1.00	23.54	11.21
Mass (M⊕)	1.00	375.04	317.83
Density (g/cm³)	5.51	0.07	1.33
Surface Gravity (g)	1.00	0.68	2.53
Insolation (S⊕)	1.00	841.30	0.037

Alternative Mass Estimates

Method	Value	Interpretation
Best measured mass	375.038 M⊕	Direct mass measurement (not derived).

Star Catalogue Identifiers

TIC

TIC 17865622

Gaia DR2

Gaia DR2 1896138833241139584

Gaia DR3

Gaia DR3 1896138833241139584

System

TOI-3540

Percentile among Gas Giant cohort

Radius 23.539 R⊕ · percentile 99 / cohort 1771

Mass 375.038 M⊕ · percentile 40 / cohort 1747

Orbital period 3.12 d · percentile 17 / cohort 1533

ESI 0.045 · percentile 3 / cohort 1771

Orbit & Habitability

Orbital Dynamics

Period

3.120 days

Semi-major axis

0.0429 AU

Eccentricity

0.000

Inclination

81.93 °

Year Length

A year here lasts approximately 3.12 Earth days (0.9% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.0429 AU.

Transit Fingerprint

Depth

0.023 %

Duration

1.901 h

Impact parameter b

1.073

Transit midpoint (BJD)

2,459,109.1411

Photometric dip

Transit produces a flux drop of 230 ppm lasting ≈ 1.90 h.

Extended Orbital Architecture

Semi-major axis / stellar radius

7.510

Impact parameter (b)

1.073

RV semi-amplitude (K)

155.000 m/s

Transit mid-time (BJD)

2,459,109.1411

Eq. Temperature

1,498K

(1225 °C)

Insolation (S⊕)

841.30

Earth = 1.00

Earth Similarity (ESI)

0.045

0 = alien, 1 = Earth-identical

Inside the inner HZ boundary (too hot for liquid water) — the dayside is scorched.

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

Yee et al. 2022

Instrument

TESS CCD Array

Publication

2022-08

Observation locale

Space

Discovery cohort

Planets confirmed in 2022 at Transiting Exoplanet Survey Satellite (TESS) (12 shown).

TOI-1452 b · Super-Earth TOI-712 d · Sub-Neptune TOI-1468 c · Sub-Neptune TOI-2136 b · Sub-Neptune LTT 1445 A c · Rocky Terrestrial TOI-712 c · Sub-Neptune LP 890-9 b · Super-Earth TOI-2081 b · Sub-Neptune GJ 3929 b · Rocky Terrestrial HD 260655 c · Super-Earth HD 73583 c · Sub-Neptune TOI-1759 b · Sub-Neptune

Host System: TOI-3540 A

Spectral Class

G-type yellow (Sun-like)

Effective Temperature

5,810 K — hotter than the Sun (5,778 K)

Estimated Age

6.00 Gyr — older than the Sun (4.6 Gyr)

Stellar Radius

1.228 R☉

Stellar Mass

1.081 M☉

Metallicity [Fe/H]

0.18

Extended Stellar Properties

Surface gravity (log g)

4.293 dex

Stellar density

0.823 g/cm³

Metallicity ratio

[Fe/H]

Multi-band Host Photometry — 16 bands

Astrometric Data

Total Proper Motion

8.818 mas/yr

PM Right Ascension

8.41 mas/yr

PM Declination

2.65 mas/yr

Galactic Cartesian (pc)

x = 0.755 · y = -0.455 · z = 0.472

Equatorial (J2000)

RA 328.91137° · Dec 28.17950°

Galactic ℓ, b

82.170° · -20.456°

Ecliptic λ, β

343.068° · 37.903°

HTM-20 index

-877250870