Confirmed Exoplanet Discovered 2021

TOI-1260 b

A sub-neptune orbiting the k-type orange TOI-1260, located approximately 240.0 light-years from Earth.

Key parameters at a glance

  • A radius of 2.41 Earth radii
  • A mass of 8.56 Earth masses
  • Surface gravity around 1.47 g
  • An orbital period of 3.127 days
  • Semi-major axis 0.0367 AU
  • Equilibrium temperature 871 K (598 °C)
  • Distance from Earth 240.04 light-years
  • Earth Similarity Index 0.304
  • Travel time at Voyager 1 speed 4,233,164 years
  • Almost certainly tidally locked to its host star given the close orbit

2 siblings around TOI-1260

TOI-1260 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-1260 b this Sub-Neptune 2.41 8.56 3.127 871 2021
TOI-1260 c Sub-Neptune 2.76 13.20 7.493 651 2021
TOI-1260 d Sub-Neptune 3.12 11.84 16.608 499 2022

TOI-1260 b Planet Profile

Physical Specs

Radius
2.41 R⊕
Radius (Jupiter)
0.215 R♃
Mass
8.56 M⊕
Mass (Jupiter)
0.027 M♃
Density
3.35 g/cm³
Surface Gravity
1.47 g (Earth)

Classification

Planet Type

Sub-Neptune

ESI Score 0.304
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

#1312of 1978

top 66.3%

This planet

2.41R⊕

Sub-Neptune median

2.71R⊕

Nearest-size peers

Kepler-143 b 2.41 R⊕ Kepler-343 b 2.41 R⊕ GJ 536 b 2.41 R⊕
Metric Earth TOI-1260 b Jupiter
Radius (R⊕)1.002.4111.21
Mass (M⊕)1.008.56317.83
Density (g/cm³)5.513.351.33
Surface Gravity (g)1.001.472.53
Insolation (S⊕)1.0095.580.037

Alternative Mass Estimates

Method Value Interpretation
Best measured mass 8.560 M⊕ Direct mass measurement (not derived).

Star Catalogue Identifiers

TIC

TIC 355867695

Gaia DR2

Gaia DR2 1053809778428567680

Gaia DR3

Gaia DR3 1053809778428567680

System

TOI-1260

Percentile among Sub-Neptune cohort

Radius 2.410 R⊕ · percentile 33 / cohort 1978
Mass 8.560 M⊕ · percentile 61 / cohort 1978
Orbital period 3.13 d · percentile 5 / cohort 1946
Distance 73.60 pc · percentile 16 / cohort 1975
ESI 0.304 · percentile 29 / cohort 1978

Orbit & Habitability

Orbital Dynamics

Period
3.127 days
Semi-major axis
0.0367 AU
Eccentricity
0.000
Inclination
89.03 °

Year Length

A year here lasts approximately 3.13 Earth days (0.9% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.0367 AU.

Transit Fingerprint

Depth

0.108 %

Duration

2.060 h

Impact parameter b

0.200

Rp / R★

0.032900

Transit midpoint (BJD)

2,459,065.5643

Photometric dip

Transit produces a flux drop of 1,082 ppm lasting ≈ 2.06 h.

Extended Orbital Architecture

Planet / star radius ratio

0.032900

Semi-major axis / stellar radius

11.730

Impact parameter (b)

0.200

RV semi-amplitude (K)

4.930 m/s

Transit mid-time (BJD)

2,459,065.5643

Long. of periastron (ω)

0.00°

Angular separation (arcsec)

0.49900

Eq. Temperature

871K

(598 °C)

Insolation (S⊕)

95.58

Earth = 1.00

Earth Similarity (ESI)

0.304

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.

Discovery Paper

Primary reference

Georgieva et al. 2021

Instrument

TESS CCD Array

Publication

2021-08

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-1260

Spectral Class

K-type orange

Effective Temperature

4,227 K — cooler than the Sun (5,778 K)

Estimated Age

6.70 Gyr — older than the Sun (4.6 Gyr)

Stellar Radius

0.672 R☉

Stellar Mass

0.679 M☉

Metallicity [Fe/H]

-0.10

Extended Stellar Properties

Surface gravity (log g)

4.570 dex

Stellar density

3.430 g/cm³

Rotational v·sin i

1.50 km/s

Rotation period

30.63 days

Activity index (log R'HK)

-4.860

Metallicity ratio

[Fe/H]

Distance
73.60 parsec
Light-years 240.04 ly
V-band magnitude
11.92 mag
Voyager-speed travel 4,233,164 yr

Multi-band Host Photometry — 11 bands

8.913.313.34B11.92V11.57Gaia10.81TESS9.70J9.11H8.95K8.89W18.96W28.88W39.22W4

Astrometric Data

Parallax

13.559 mas

Total Proper Motion

195.190 mas/yr

PM Right Ascension

-177.24 mas/yr

PM Declination

-81.77 mas/yr

Galactic Cartesian (pc)

x = -0.377 · y = 0.159 · z = 0.913

Equatorial (J2000)

RA 157.14407° · Dec 65.85420°

Galactic ℓ, b

142.804° · 45.372°

Ecliptic λ, β

126.532° · 50.715°

HTM-20 index

-454174731

Similar Worlds

Kepler-1170 b

Sub-Neptune · K-type orange

Radius 2.41 R⊕ · 3,426.1 ly

K2-8 c

Sub-Neptune · K-type orange

Radius 2.41 R⊕ · 1,316.1 ly

Kepler-1337 b

Sub-Neptune · K-type orange

Radius 2.41 R⊕ · 1,962.2 ly

K2-347 b

Sub-Neptune · K-type orange

Radius 2.41 R⊕ · 1,044.8 ly

K2-59 b

Sub-Neptune · K-type orange

Radius 2.41 R⊕ · 1,015.4 ly

K2-367 b

Sub-Neptune · K-type orange

Radius 2.41 R⊕ · 577.2 ly

Explore Related Categories

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