Key parameters at a glance

A radius of 1.22 Earth radii
A mass of 1.98 Earth masses
Surface gravity around 1.33 g
An orbital period of 3.805 days
Distance from Earth 1,555.38 light-years
Earth Similarity Index 0.937
Travel time at Voyager 1 speed 27,429,112 years

1 sibling around K2-166

EPIC 201615463 c shares its host star with 1 other confirmed planet. Side-by-side measurements below.

Planet	Type	Radius (R⊕)	Mass (M⊕)	Period (d)	Eq. T (K)	Year
EPIC 201615463 c this	Rocky Terrestrial	1.22	1.98	3.805	—	2019
K2-166 b	Sub-Neptune	2.19	5.43	8.527	1,140	2018

EPIC 201615463 c Planet Profile

Physical Specs

Radius

1.22 R⊕

Radius (Jupiter)

0.109 R♃

Mass

1.98 M⊕

Mass (Jupiter)

0.006 M♃

Density

5.99 g/cm³

Surface Gravity

1.33 g (Earth)

Classification

Planet Type

Rocky Terrestrial

ESI Score 0.937

HZ Position Unknown

Controversial No

Discovery

Year 2019

Method Transit

Facility K2

Telescope 0.95 m Kepler Telescope

Size rank in cohort

Rank by radius

#35of 570

top 6.0%

This planet

1.22R⊕

Rocky Terrestrial median

1.01R⊕

Nearest-size peers

Kepler-295 b 1.22 R⊕ Kepler-226 d 1.22 R⊕ Kepler-197 d 1.22 R⊕

Metric	Earth	EPIC 201615463 c	Jupiter
Radius (R⊕)	1.00	1.22	11.21
Mass (M⊕)	1.00	1.98	317.83
Density (g/cm³)	5.51	5.99	1.33
Surface Gravity (g)	1.00	1.33	2.53
Insolation (S⊕)	1.00	—	0.037

Star Catalogue Identifiers

TIC

TIC 377171980

Gaia DR2

Gaia DR2 3701015375282968064

Gaia DR3

Gaia DR3 3701015375282968064

System

K2-166

Percentile among Rocky Terrestrial cohort

Radius 1.220 R⊕ · percentile 92 / cohort 570

Mass 1.980 M⊕ · percentile 83 / cohort 570

Orbital period 3.80 d · percentile 41 / cohort 567

Distance 476.88 pc · percentile 61 / cohort 566

ESI 0.937 · percentile 92 / cohort 570

Orbit & Habitability

Orbital Dynamics

Period

3.805 days

Semi-major axis

— AU

Eccentricity

—

Inclination

— °

Year Length

A year here lasts approximately 3.80 Earth days (1.0% of a terrestrial year).

Transit Fingerprint

Impact parameter b

0.610

Rp / R★

0.009300

Transit midpoint (BJD)

2,457,621.2227

Eq. Temperature

—

Insolation (S⊕)

—

Earth = 1.00

Earth Similarity (ESI)

0.937

0 = alien, 1 = Earth-identical

Discovery Paper

Primary reference

Heller et al. 2019

Instrument

Kepler CCD Array

Publication

2019-07

Observation locale

Space

Discovery cohort

Planets confirmed in 2019 at K2 (12 shown).

EPIC 206032309 b · Rocky Terrestrial EPIC 201833600 c · Rocky Terrestrial EPIC 206215704 b · Rocky Terrestrial EPIC 201754305 d · Rocky Terrestrial EPIC 201841433 b · Rocky Terrestrial EPIC 206317286 b · Rocky Terrestrial EPIC 212499991 b · Super-Earth EPIC 220554210 c · Super-Earth EPIC 201497682 b · Rocky Terrestrial K2-133 e · Super-Earth EPIC 206024342 b · Super-Earth EPIC 206042996 b · Super-Earth

Host System: K2-166

Spectral Class

G-type yellow (Sun-like)

Effective Temperature

5,960 K — hotter than the Sun (5,778 K)

Estimated Age

—

Stellar Radius

1.610 R☉

Stellar Mass

1.073 M☉

Metallicity [Fe/H]

0.09

Extended Stellar Properties

Surface gravity (log g)

4.090 dex

Stellar density

0.423 g/cm³

Metallicity ratio

[Fe/H]

Distance

476.88 parsec

Light-years 1,555.38 ly

V-band magnitude

12.08 mag

Voyager-speed travel 27,429,112 yr

Multi-band Host Photometry — 17 bands

Astrometric Data

Parallax

2.069 mas

Total Proper Motion

49.648 mas/yr

PM Right Ascension

-47.37 mas/yr

PM Declination

-14.88 mas/yr

Galactic Cartesian (pc)

x = -0.995 · y = -0.090 · z = 0.040

Equatorial (J2000)

RA 185.18809° · Dec 2.28238°

Galactic ℓ, b

285.158° · 64.090°

Ecliptic λ, β

183.851° · 4.156°

HTM-20 index

-1616119422