Key parameters at a glance

A radius of 3.41 Earth radii
A mass of 11.50 Earth masses
Surface gravity around 0.99 g
An orbital period of 15.145 days
Semi-major axis 0.0877 AU
Equilibrium temperature 337 K (64 °C)
Distance from Earth 181.09 light-years
Earth Similarity Index 0.604
Travel time at Voyager 1 speed 3,193,441 years
Almost certainly tidally locked to its host star given the close orbit

TOI-1806.01 Planet Profile

Physical Specs

Radius

3.41 R⊕

Radius (Jupiter)

0.304 R♃

Mass

11.50 M⊕

Mass (Jupiter)

0.036 M♃

Density

1.59 g/cm³

Surface Gravity

0.99 g (Earth)

Classification

Planet Type

Sub-Neptune

ESI Score 0.604

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

#219of 1978

top 11.0%

This planet

3.41R⊕

Sub-Neptune median

2.71R⊕

Nearest-size peers

HD 191939 b 3.41 R⊕ Kepler-159 c 3.41 R⊕ Kepler-711 b 3.41 R⊕

Metric	Earth	TOI-1806.01	Jupiter
Radius (R⊕)	1.00	3.41	11.21
Mass (M⊕)	1.00	11.50	317.83
Density (g/cm³)	5.51	1.59	1.33
Surface Gravity (g)	1.00	0.99	2.53
Insolation (S⊕)	1.00	2.15	0.037

Star Catalogue Identifiers

TIC

TIC 166648874

Gaia DR2

Gaia DR2 733540939112687104

Gaia DR3

Gaia DR3 733540939112687104

System

TOI-1806

Percentile among Sub-Neptune cohort

Radius 3.410 R⊕ · percentile 89 / cohort 1978

Mass 11.500 M⊕ · percentile 83 / cohort 1978

Orbital period 15.15 d · percentile 51 / cohort 1946

Distance 55.52 pc · percentile 13 / cohort 1975

ESI 0.604 · percentile 83 / cohort 1978

Orbit & Habitability

Orbital Dynamics

Period

15.145 days

Semi-major axis

0.0877 AU

Eccentricity

—

Inclination

— °

Year Length

A year here lasts approximately 15.15 Earth days (4.1% of a terrestrial year) at a mean orbital distance of 0.0877 AU.

Transit Fingerprint

Depth

0.496 %

Duration

2.583 h

Rp / R★

0.077775

Transit midpoint (BJD)

2,458,909.5434

Photometric dip

Transit produces a flux drop of 4,955 ppm lasting ≈ 2.58 h.

Extended Orbital Architecture

Planet / star radius ratio

0.077775

Semi-major axis / stellar radius

47.003

Transit mid-time (BJD)

2,458,909.5434

Angular separation (arcsec)

1.58000

Eq. Temperature

337K

(64 °C)

Insolation (S⊕)

2.15

Earth = 1.00

Earth Similarity (ESI)

0.604

0 = alien, 1 = Earth-identical

Inside the inner HZ boundary (too hot for liquid water) — liquid water is physically possible with adequate atmospheric pressure. Close-orbiting tidally-locked around a cool host.

Discovery Paper

Primary reference

Hord et al. 2024

Instrument

TESS CCD Array

Publication

2024-05

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-4633 c · Sub-Neptune TOI-260 b · Super-Earth TOI-663 d · Super-Earth

Host System: TOI-1806

Spectral Class

M-type red dwarf

Effective Temperature

3,272 K — cooler than the Sun (5,778 K)

Estimated Age

—

Stellar Radius

0.402 R☉

Stellar Mass

0.393 M☉

Metallicity [Fe/H]

—

Distance

55.52 parsec

Light-years 181.09 ly

V-band magnitude

15.19 mag

Voyager-speed travel 3,193,441 yr

Multi-band Host Photometry — 11 bands

Astrometric Data

Parallax

17.983 mas

Total Proper Motion

168.204 mas/yr

PM Right Ascension

-163.27 mas/yr

PM Declination

-40.43 mas/yr

Galactic Cartesian (pc)

x = -0.837 · y = 0.207 · z = 0.507

Equatorial (J2000)

RA 166.11815° · Dec 30.45858°

Galactic ℓ, b

198.457° · 66.385°

Ecliptic λ, β

154.930° · 22.509°

HTM-20 index

1301748059