Key parameters at a glance

A radius of 3.64 Earth radii
A mass of 12.90 Earth masses
Surface gravity around 0.97 g
An orbital period of 39.721 days
Distance from Earth 2,053.18 light-years
Earth Similarity Index 0.575
Travel time at Voyager 1 speed 36,207,909 years

K2-194 b Planet Profile

Physical Specs

Radius

3.64 R⊕

Radius (Jupiter)

0.325 R♃

Mass

12.90 M⊕

Mass (Jupiter)

0.041 M♃

Density

1.47 g/cm³

Surface Gravity

0.97 g (Earth)

Classification

Planet Type

Sub-Neptune

ESI Score 0.575

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

#119of 1978

top 6.0%

This planet

3.64R⊕

Sub-Neptune median

2.71R⊕

Nearest-size peers

Kepler-565 b 3.64 R⊕ Kepler-1635 b 3.64 R⊕ Kepler-608 b 3.64 R⊕

Metric	Earth	K2-194 b	Jupiter
Radius (R⊕)	1.00	3.64	11.21
Mass (M⊕)	1.00	12.90	317.83
Density (g/cm³)	5.51	1.47	1.33
Surface Gravity (g)	1.00	0.97	2.53
Insolation (S⊕)	1.00	—	0.037

Star Catalogue Identifiers

TIC

TIC 706595

Gaia DR2

Gaia DR2 3618361345307363584

Gaia DR3

Gaia DR3 3618361345307363584

System

K2-194

Percentile among Sub-Neptune cohort

Radius 3.642 R⊕ · percentile 94 / cohort 1978

Mass 12.900 M⊕ · percentile 87 / cohort 1978

Orbital period 39.72 d · percentile 80 / cohort 1946

Distance 629.51 pc · percentile 55 / cohort 1975

ESI 0.575 · percentile 80 / cohort 1978

Orbit & Habitability

Orbital Dynamics

Period

39.721 days

Semi-major axis

— AU

Eccentricity

—

Inclination

89.07 °

Year Length

A year here lasts approximately 39.72 Earth days (10.9% of a terrestrial year).

Transit Fingerprint

Depth

0.074 %

Duration

8.520 h

Impact parameter b

0.273

Rp / R★

0.026065

Transit midpoint (BJD)

2,457,243.0070

Photometric dip

Transit produces a flux drop of 741 ppm lasting ≈ 8.52 h.

Extended Orbital Architecture

Planet / star radius ratio

0.026065

Semi-major axis / stellar radius

30.989

Impact parameter (b)

0.273

Transit mid-time (BJD)

2,457,243.0070

Eq. Temperature

—

Insolation (S⊕)

—

Earth = 1.00

Earth Similarity (ESI)

0.575

0 = alien, 1 = Earth-identical

Discovery Paper

Primary reference

Mayo et al. 2018

Instrument

Kepler CCD Array

Publication

2018-03

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: K2-194

Spectral Class

G-type yellow (Sun-like)

Effective Temperature

5,979 K — hotter than the Sun (5,778 K)

Estimated Age

—

Stellar Radius

1.281 R☉

Stellar Mass

1.110 M☉

Metallicity [Fe/H]

0.10

Extended Stellar Properties

Surface gravity (log g)

4.210 dex

Stellar density

0.750 g/cm³

Systemic radial velocity

-7.95 km/s

Metallicity ratio

[Fe/H]

Distance

629.51 parsec

Light-years 2,053.18 ly

V-band magnitude

13.00 mag

Voyager-speed travel 36,207,909 yr

Multi-band Host Photometry — 12 bands

Astrometric Data

Parallax

1.561 mas

Total Proper Motion

11.349 mas/yr

PM Right Ascension

11.18 mas/yr

PM Declination

-1.96 mas/yr

Galactic Cartesian (pc)

x = -0.898 · y = -0.411 · z = -0.155

Equatorial (J2000)

RA 204.60898° · Dec -8.92716°

Galactic ℓ, b

322.087° · 52.188°

Ecliptic λ, β

206.053° · 1.218°

HTM-20 index

-786447862