Key parameters at a glance

A radius of 1.68 Earth radii
A mass of 3.45 Earth masses
Surface gravity around 1.23 g
An orbital period of 20.979 days
Distance from Earth 529.37 light-years
Earth Similarity Index 0.851
Travel time at Voyager 1 speed 9,335,453 years

K2-408 b Planet Profile

Physical Specs

Radius

1.68 R⊕

Radius (Jupiter)

0.150 R♃

Mass

3.45 M⊕

Mass (Jupiter)

0.011 M♃

Density

4.02 g/cm³

Surface Gravity

1.23 g (Earth)

Classification

Planet Type

Super-Earth

ESI Score 0.851

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

#447of 1176

top 37.9%

This planet

1.68R⊕

Super-Earth median

1.60R⊕

Nearest-size peers

K2-221 b 1.68 R⊕ K2-208 b 1.67 R⊕ Kepler-167 c 1.67 R⊕

Metric	Earth	K2-408 b	Jupiter
Radius (R⊕)	1.00	1.68	11.21
Mass (M⊕)	1.00	3.45	317.83
Density (g/cm³)	5.51	4.02	1.33
Surface Gravity (g)	1.00	1.23	2.53
Insolation (S⊕)	1.00	—	0.037

Star Catalogue Identifiers

TIC

TIC 432247186

Gaia DR2

Gaia DR2 6257641627989839744

Gaia DR3

Gaia DR3 6257641627989839744

System

K2-408

Percentile among Super-Earth cohort

Radius 1.677 R⊕ · percentile 62 / cohort 1176

Mass 3.450 M⊕ · percentile 56 / cohort 1176

Orbital period 20.98 d · percentile 86 / cohort 1164

Distance 162.31 pc · percentile 21 / cohort 1171

ESI 0.851 · percentile 94 / cohort 1176

Orbit & Habitability

Orbital Dynamics

Period

20.979 days

Semi-major axis

— AU

Eccentricity

—

Inclination

— °

Year Length

A year here lasts approximately 20.98 Earth days (5.7% of a terrestrial year).

Transit Fingerprint

Duration

4.400 h

Impact parameter b

0.213

Rp / R★

0.019600

Transit midpoint (BJD)

2,457,991.5363

Extended Orbital Architecture

Planet / star radius ratio

0.019600

Semi-major axis / stellar radius

36.240

Impact parameter (b)

0.213

Transit mid-time (BJD)

2,457,991.5363

Eq. Temperature

—

Insolation (S⊕)

—

Earth = 1.00

Earth Similarity (ESI)

0.851

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: K2-408

Spectral Class

G-type yellow (Sun-like)

Effective Temperature

5,335 K — cooler than the Sun (5,778 K)

Estimated Age

—

Stellar Radius

0.784 R☉

Stellar Mass

0.813 M☉

Metallicity [Fe/H]

-0.17

Extended Stellar Properties

Surface gravity (log g)

4.559 dex

Stellar density

2.295 g/cm³

Metallicity ratio

[Fe/H]

Distance

162.31 parsec

Light-years 529.37 ly

V-band magnitude

12.06 mag

Voyager-speed travel 9,335,453 yr

Multi-band Host Photometry — 12 bands

Astrometric Data

Parallax

6.133 mas

Total Proper Motion

96.212 mas/yr

PM Right Ascension

-90.91 mas/yr

PM Declination

-31.49 mas/yr

Galactic Cartesian (pc)

x = -0.639 · y = -0.707 · z = -0.304

Equatorial (J2000)

RA 227.91686° · Dec -17.68427°

Galactic ℓ, b

344.093° · 33.751°

Ecliptic λ, β

230.313° · 0.147°

HTM-20 index

-1167051463