Key parameters at a glance

A radius of 3.49 Earth radii
A mass of 12.00 Earth masses
Surface gravity around 0.99 g
An orbital period of 5.769 days
Semi-major axis 0.0602 AU
Equilibrium temperature 977 K (704 °C)
Distance from Earth 2,294.89 light-years
Earth Similarity Index 0.224
Travel time at Voyager 1 speed 40,470,309 years

K2-246 b Planet Profile

Physical Specs

Radius

3.49 R⊕

Radius (Jupiter)

0.311 R♃

Mass

12.00 M⊕

Mass (Jupiter)

0.038 M♃

Density

1.55 g/cm³

Surface Gravity

0.99 g (Earth)

Classification

Planet Type

Sub-Neptune

ESI Score 0.224

HZ Position Unknown

Controversial No

Discovery

Year 2018

Method Transit

Facility K2

Telescope 0.95 m Kepler Telescope

Size rank in cohort

Rank by radius

#184of 1978

top 9.3%

This planet

3.49R⊕

Sub-Neptune median

2.71R⊕

Nearest-size peers

HD 183579 b 3.49 R⊕ Kepler-10 d 3.49 R⊕ Kepler-79 e 3.49 R⊕

Metric	Earth	K2-246 b	Jupiter
Radius (R⊕)	1.00	3.49	11.21
Mass (M⊕)	1.00	12.00	317.83
Density (g/cm³)	5.51	1.55	1.33
Surface Gravity (g)	1.00	0.99	2.53
Insolation (S⊕)	1.00	—	0.037

Star Catalogue Identifiers

TIC

TIC 56721373

Gaia DR2

Gaia DR2 3697828548204889344

Gaia DR3

Gaia DR3 3697828548204889344

System

K2-246

Percentile among Sub-Neptune cohort

Radius 3.490 R⊕ · percentile 91 / cohort 1978

Mass 12.000 M⊕ · percentile 84 / cohort 1978

Orbital period 5.77 d · percentile 16 / cohort 1946

Distance 703.62 pc · percentile 60 / cohort 1975

ESI 0.224 · percentile 10 / cohort 1978

Orbit & Habitability

Orbital Dynamics

Period

5.769 days

Semi-major axis

0.0602 AU

Eccentricity

—

Inclination

— °

Year Length

A year here lasts approximately 5.77 Earth days (1.6% of a terrestrial year) at a mean orbital distance of 0.0602 AU.

Transit Fingerprint

Depth

0.134 %

Duration

3.400 h

Impact parameter b

0.410

Rp / R★

0.034100

Transit midpoint (BJD)

2,457,583.6761

Photometric dip

Transit produces a flux drop of 1,340 ppm lasting ≈ 3.40 h.

Extended Orbital Architecture

Planet / star radius ratio

0.034100

Semi-major axis / stellar radius

11.100

Impact parameter (b)

0.410

Transit mid-time (BJD)

2,457,583.6761

Angular separation (arcsec)

0.08560

Eq. Temperature

977K

(704 °C)

Insolation (S⊕)

—

Earth = 1.00

Earth Similarity (ESI)

0.224

0 = alien, 1 = Earth-identical

Insufficient insolation data — the surface is too hot to retain surface water.

Discovery Paper

Primary reference

Livingston et al. 2018

Instrument

Kepler CCD Array

Publication

2018-08

Observation locale

Space

Discovery cohort

Planets confirmed in 2018 at K2 (12 shown).

K2-190 c · Rocky Terrestrial K2-183 b · Rocky Terrestrial K2-209 b · Rocky Terrestrial K2-210 b · Rocky Terrestrial K2-165 b · Super-Earth K2-169 b · Super-Earth K2-148 b · Super-Earth K2-219 b · Super-Earth K2-190 b · Super-Earth K2-200 b · Super-Earth K2-201 b · Super-Earth K2-170 b · Super-Earth

Host System: K2-246

Spectral Class

G-type yellow (Sun-like)

Effective Temperature

5,610 K — cooler than the Sun (5,778 K)

Estimated Age

—

Stellar Radius

0.940 R☉

Stellar Mass

0.870 M☉

Metallicity [Fe/H]

-0.19

Extended Stellar Properties

Surface gravity (log g)

4.430 dex

Stellar density

1.681 g/cm³

Rotational v·sin i

2.90 km/s

Metallicity ratio

[Fe/H]

Distance

703.62 parsec

Light-years 2,294.89 ly

V-band magnitude

14.79 mag

Voyager-speed travel 40,470,309 yr

Multi-band Host Photometry — 12 bands

Astrometric Data

Parallax

1.393 mas

Total Proper Motion

24.270 mas/yr

PM Right Ascension

-21.49 mas/yr

PM Declination

-11.27 mas/yr

Galactic Cartesian (pc)

x = -0.999 · y = -0.028 · z = -0.020

Equatorial (J2000)

RA 181.62961° · Dec -1.16060°

Galactic ℓ, b

280.220° · 59.716°

Ecliptic λ, β

181.953° · -0.417°

HTM-20 index

677725519