Key parameters at a glance

A radius of 2.59 Earth radii
A mass of 9.60 Earth masses
Surface gravity around 1.43 g
An orbital period of 8.595 days
Semi-major axis 0.0750 AU
Equilibrium temperature 665 K (392 °C)
Distance from Earth 89.70 light-years
Earth Similarity Index 0.390
Travel time at Voyager 1 speed 1,581,872 years
Almost certainly tidally locked to its host star given the close orbit

1 sibling around TOI-836

TOI-836.01 shares its host star with 1 other confirmed planet. Side-by-side measurements below.

Planet	Type	Radius (R⊕)	Mass (M⊕)	Period (d)	Eq. T (K)	Year
TOI-836 b	Super-Earth	1.70	4.53	3.817	871	2023
TOI-836.01 this	Sub-Neptune	2.59	9.60	8.595	665	2021

TOI-836.01 Planet Profile

Physical Specs

Radius

2.59 R⊕

Radius (Jupiter)

0.231 R♃

Mass

9.60 M⊕

Mass (Jupiter)

0.030 M♃

Density

3.06 g/cm³

Surface Gravity

1.43 g (Earth)

Classification

Planet Type

Sub-Neptune

ESI Score 0.390

HZ Position Inner

Controversial No

Discovery

Year 2021

Method Transit

Facility Transiting Exoplanet Survey Satellite (TESS)

Telescope 0.1 m TESS Telescope

Size rank in cohort

Rank by radius

#1052of 1978

top 53.1%

This planet

2.59R⊕

Sub-Neptune median

2.71R⊕

Nearest-size peers

TOI-1064 b 2.59 R⊕ Kepler-1854 b 2.59 R⊕ TOI-669 b 2.59 R⊕

Metric	Earth	TOI-836.01	Jupiter
Radius (R⊕)	1.00	2.59	11.21
Mass (M⊕)	1.00	9.60	317.83
Density (g/cm³)	5.51	3.06	1.33
Surface Gravity (g)	1.00	1.43	2.53
Insolation (S⊕)	1.00	26.71	0.037

Alternative Mass Estimates

Method	Value	Interpretation
Best measured mass	9.600 M⊕	Direct mass measurement (not derived).

Star Catalogue Identifiers

HIP

HIP 73427

TIC

TIC 440887364

Gaia DR2

Gaia DR2 6230733559097425152

Gaia DR3

Gaia DR3 6230733559097425152

System

TOI-836

Percentile among Sub-Neptune cohort

Radius 2.587 R⊕ · percentile 47 / cohort 1978

Mass 9.600 M⊕ · percentile 70 / cohort 1978

Orbital period 8.60 d · percentile 28 / cohort 1946

Distance 27.50 pc · percentile 7 / cohort 1975

ESI 0.390 · percentile 50 / cohort 1978

Orbit & Habitability

Orbital Dynamics

Period

8.595 days

Semi-major axis

0.0750 AU

Eccentricity

0.078

Inclination

88.70 °

Year Length

A year here lasts approximately 8.60 Earth days (2.4% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.0750 AU.

Transit Fingerprint

Depth

0.114 %

Duration

2.486 h

Impact parameter b

0.530

Rp / R★

0.035700

Transit midpoint (BJD)

2,458,599.7623

Photometric dip

Transit produces a flux drop of 1,140 ppm lasting ≈ 2.49 h.

Extended Orbital Architecture

Planet / star radius ratio

0.035700

Impact parameter (b)

0.530

RV semi-amplitude (K)

3.860 m/s

Transit mid-time (BJD)

2,458,599.7623

Long. of periastron (ω)

-28.00°

Angular separation (arcsec)

2.73000

Eq. Temperature

665K

(392 °C)

Insolation (S⊕)

26.71

Earth = 1.00

Earth Similarity (ESI)

0.390

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.

Detection Signatures

Transit photometry

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

Radial velocity

Stellar wobble has been measured spectroscopically.

Transit timing variations

Gravitational interactions from neighbours have been detected.

Discovery Paper

Primary reference

Giacalone et al. 2021

Instrument

TESS CCD Array

Publication

2021-01

Observation locale

Space

Discovery cohort

Planets confirmed in 2021 at Transiting Exoplanet Survey Satellite (TESS) (12 shown).

TOI-2257 b · Sub-Neptune TOI-2285 b · Super-Earth TOI-1231 b · Sub-Neptune AU Mic c · Sub-Neptune LHS 1678 c · Rocky Terrestrial LHS 1478 b · Rocky Terrestrial TOI-2406 b · Sub-Neptune HD 207897 b · Sub-Neptune TOI-269 b · Sub-Neptune TIC 172900988 b · Gas Giant TOI-178 g · Sub-Neptune TOI-2076 d · Sub-Neptune

Host System: TOI-836

Spectral Class

K-type orange

Effective Temperature

4,552 K — cooler than the Sun (5,778 K)

Estimated Age

5.40 Gyr — older than the Sun (4.6 Gyr)

Stellar Radius

0.665 R☉

Stellar Mass

0.678 M☉

Metallicity [Fe/H]

-0.28

Extended Stellar Properties

Surface gravity (log g)

4.743 dex

Stellar density

3.294 g/cm³

Rotational v·sin i

1.86 km/s

Rotation period

21.99 days

Metallicity ratio

[Fe/H]

Distance

27.50 parsec

Light-years 89.70 ly

V-band magnitude

9.92 mag

Voyager-speed travel 1,581,872 yr

Multi-band Host Photometry — 11 bands

Astrometric Data

Parallax

36.332 mas

Total Proper Motion

201.518 mas/yr

PM Right Ascension

-199.58 mas/yr

PM Declination

-27.91 mas/yr

Galactic Cartesian (pc)

x = -0.643 · y = -0.645 · z = -0.414

Equatorial (J2000)

RA 225.07988° · Dec -24.45420°

Galactic ℓ, b

336.931° · 29.777°

Ecliptic λ, β

229.626° · -7.089°

HTM-20 index

21880269

Similar Worlds

TOI-1064 b

Sub-Neptune · K-type orange

Radius 2.59 R⊕ · 222.0 ly

Kepler-1854 b

Sub-Neptune · K-type orange

Radius 2.59 R⊕ · 1,380.8 ly

EPIC 212737443 b

Sub-Neptune · K-type orange

Radius 2.59 R⊕ · 1,096.7 ly

TOI-2076 b

Sub-Neptune · K-type orange

Radius 2.59 R⊕ · 136.7 ly

K2-285 b

Sub-Neptune · K-type orange

Radius 2.59 R⊕ · 505.4 ly

Kepler-1388 b

Sub-Neptune · K-type orange

Radius 2.59 R⊕ · 1,480.1 ly

Explore Related Categories

Sub-Neptune Planets Transit Discoveries Transiting Exoplanet Survey Satellite (TESS) Mission K-type orange Hosts