Key parameters at a glance

A radius of 2.54 Earth radii
A mass of 6.99 Earth masses
Surface gravity around 1.08 g
An orbital period of 7.806 days
Equilibrium temperature 934 K (661 °C)
Distance from Earth 2,265.92 light-years
Earth Similarity Index 0.267
Travel time at Voyager 1 speed 39,959,437 years

K2-351 b Planet Profile

Physical Specs

Radius

2.54 R⊕

Radius (Jupiter)

0.227 R♃

Mass

6.99 M⊕

Mass (Jupiter)

0.022 M♃

Density

2.34 g/cm³

Surface Gravity

1.08 g (Earth)

Classification

Planet Type

Sub-Neptune

ESI Score 0.267

HZ Position Unknown

Controversial No

Discovery

Year 2021

Method Transit

Facility K2

Telescope 0.95 m Kepler Telescope

Size rank in cohort

Rank by radius

#1117of 1978

top 56.4%

This planet

2.54R⊕

Sub-Neptune median

2.71R⊕

Nearest-size peers

Kepler-1116 b 2.54 R⊕ Kepler-325 c 2.54 R⊕ HD 189567 c 2.54 R⊕

Metric	Earth	K2-351 b	Jupiter
Radius (R⊕)	1.00	2.54	11.21
Mass (M⊕)	1.00	6.99	317.83
Density (g/cm³)	5.51	2.34	1.33
Surface Gravity (g)	1.00	1.08	2.53
Insolation (S⊕)	1.00	—	0.037

Star Catalogue Identifiers

TIC

TIC 187273748

Gaia DR2

Gaia DR2 3613442989278322432

Gaia DR3

Gaia DR3 3613442989278322432

System

K2-351

Percentile among Sub-Neptune cohort

Radius 2.540 R⊕ · percentile 43 / cohort 1978

Mass 6.990 M⊕ · percentile 40 / cohort 1978

Orbital period 7.81 d · percentile 25 / cohort 1946

Distance 694.73 pc · percentile 59 / cohort 1975

ESI 0.267 · percentile 20 / cohort 1978

Orbit & Habitability

Orbital Dynamics

Period

7.806 days

Semi-major axis

— AU

Eccentricity

—

Inclination

— °

Year Length

A year here lasts approximately 7.81 Earth days (2.1% of a terrestrial year).

Transit Fingerprint

Depth

0.068 %

Duration

2.780 h

Impact parameter b

0.390

Rp / R★

0.022100

Transit midpoint (BJD)

2,457,223.4952

Photometric dip

Transit produces a flux drop of 681 ppm lasting ≈ 2.78 h.

Extended Orbital Architecture

Planet / star radius ratio

0.022100

Semi-major axis / stellar radius

20.200

Impact parameter (b)

0.390

Transit mid-time (BJD)

2,457,223.4952

Eq. Temperature

934K

(661 °C)

Insolation (S⊕)

—

Earth = 1.00

Earth Similarity (ESI)

0.267

0 = alien, 1 = Earth-identical

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

Discovery Paper

Primary reference

De Leon et al. 2021

Instrument

Kepler CCD Array

Publication

2021-08

Observation locale

Space

Discovery cohort

Planets confirmed in 2021 at K2 (12 shown).

EPIC 220492298 b · Rocky Terrestrial EPIC 206042996 c · Rocky Terrestrial EPIC 212624936 b · Rocky Terrestrial EPIC 206024342 c · Super-Earth EPIC 201427007 b · Super-Earth K2-332 b · Sub-Neptune EPIC 212624936 c · Sub-Neptune EPIC 206024342 d · Sub-Neptune K2-345 b · Sub-Neptune K2-349 b · Super-Earth K2-343 c · Sub-Neptune K2-346 b · Sub-Neptune

Host System: K2-351

Spectral Class

G-type yellow (Sun-like)

Effective Temperature

5,769 K — cooler than the Sun (5,778 K)

Estimated Age

—

Stellar Radius

1.050 R☉

Stellar Mass

1.020 M☉

Metallicity [Fe/H]

0.08

Extended Stellar Properties

Surface gravity (log g)

4.400 dex

Stellar density

1.292 g/cm³

Rotation period

25.23 days

Metallicity ratio

[Fe/H]

Distance

694.73 parsec

Light-years 2,265.92 ly

V-band magnitude

14.20 mag

Voyager-speed travel 39,959,437 yr

Multi-band Host Photometry — 12 bands

Astrometric Data

Parallax

1.411 mas

Total Proper Motion

16.748 mas/yr

PM Right Ascension

-16.71 mas/yr

PM Declination

1.12 mas/yr

Galactic Cartesian (pc)

x = -0.875 · y = -0.439 · z = -0.205

Equatorial (J2000)

RA 206.65224° · Dec -11.80496°

Galactic ℓ, b

323.695° · 48.830°

Ecliptic λ, β

208.961° · -0.747°

HTM-20 index

499072086