Key parameters at a glance

A radius of 2.68 Earth radii
A mass of 7.65 Earth masses
Surface gravity around 1.07 g
An orbital period of 17.275 days
Distance from Earth 1,705.98 light-years
Earth Similarity Index 0.680
Travel time at Voyager 1 speed 30,084,872 years

K2-402 b Planet Profile

Physical Specs

Radius

2.68 R⊕

Radius (Jupiter)

0.239 R♃

Mass

7.65 M⊕

Mass (Jupiter)

0.024 M♃

Density

2.19 g/cm³

Surface Gravity

1.07 g (Earth)

Classification

Planet Type

Sub-Neptune

ESI Score 0.680

HZ Position Unknown

Controversial No

Discovery

Year 2022

Method Transit

Facility K2

Telescope 0.95 m Kepler Telescope

Size rank in cohort

Rank by radius

#903of 1978

top 45.6%

This planet

2.68R⊕

Sub-Neptune median

2.71R⊕

Nearest-size peers

Kepler-487 c 2.68 R⊕ Kepler-1184 b 2.68 R⊕ K2-58 b 2.68 R⊕

Metric	Earth	K2-402 b	Jupiter
Radius (R⊕)	1.00	2.68	11.21
Mass (M⊕)	1.00	7.65	317.83
Density (g/cm³)	5.51	2.19	1.33
Surface Gravity (g)	1.00	1.07	2.53
Insolation (S⊕)	1.00	—	0.037

Star Catalogue Identifiers

TIC

TIC 393548451

Gaia DR2

Gaia DR2 3865287467650348928

Gaia DR3

Gaia DR3 3865287467650348928

System

K2-402

Percentile among Sub-Neptune cohort

Radius 2.678 R⊕ · percentile 54 / cohort 1978

Mass 7.650 M⊕ · percentile 50 / cohort 1978

Orbital period 17.27 d · percentile 57 / cohort 1946

Distance 523.06 pc · percentile 48 / cohort 1975

ESI 0.680 · percentile 91 / cohort 1978

Orbit & Habitability

Orbital Dynamics

Period

17.275 days

Semi-major axis

— AU

Eccentricity

—

Inclination

— °

Year Length

A year here lasts approximately 17.27 Earth days (4.7% of a terrestrial year).

Transit Fingerprint

Duration

5.200 h

Impact parameter b

0.468

Rp / R★

0.019200

Transit midpoint (BJD)

2,457,920.4286

Extended Orbital Architecture

Planet / star radius ratio

0.019200

Semi-major axis / stellar radius

23.110

Impact parameter (b)

0.468

Transit mid-time (BJD)

2,457,920.4286

Eq. Temperature

—

Insolation (S⊕)

—

Earth = 1.00

Earth Similarity (ESI)

0.680

0 = alien, 1 = Earth-identical

Discovery Paper

Primary reference

Christiansen et al. 2022

Instrument

Kepler CCD Array

Publication

2022-03

Observation locale

Space

Discovery cohort

Planets confirmed in 2022 at K2 (12 shown).

K2-411 b · Rocky Terrestrial K2-381 b · Rocky Terrestrial K2-384 b · Rocky Terrestrial K2-400 b · Rocky Terrestrial K2-384 c · Rocky Terrestrial K2-369 b · Super-Earth K2-407 b · Super-Earth K2-414 b · Rocky Terrestrial K2-368 b · Super-Earth K2-413 c · Rocky Terrestrial K2-384 e · Super-Earth K2-407 c · Super-Earth

Host System: K2-402

Spectral Class

G-type yellow (Sun-like)

Effective Temperature

5,716 K — cooler than the Sun (5,778 K)

Estimated Age

—

Stellar Radius

1.280 R☉

Stellar Mass

0.944 M☉

Metallicity [Fe/H]

-0.38

Extended Stellar Properties

Surface gravity (log g)

4.197 dex

Stellar density

0.767 g/cm³

Metallicity ratio

[Fe/H]

Distance

523.06 parsec

Light-years 1,705.98 ly

V-band magnitude

13.03 mag

Voyager-speed travel 30,084,872 yr

Multi-band Host Photometry — 17 bands

Astrometric Data

Parallax

1.884 mas

Total Proper Motion

18.598 mas/yr

PM Right Ascension

0.98 mas/yr

PM Declination

-18.57 mas/yr

Galactic Cartesian (pc)

x = -0.942 · y = 0.316 · z = 0.112

Equatorial (J2000)

RA 161.45191° · Dec 6.41932°

Galactic ℓ, b

241.947° · 53.688°

Ecliptic λ, β

160.449° · -1.327°

HTM-20 index

-1222854828