Key parameters at a glance

A radius of 3.13 Earth radii
A mass of 9.96 Earth masses
Surface gravity around 1.02 g
An orbital period of 15.853 days
Semi-major axis 0.1208 AU
Equilibrium temperature 720 K (447 °C)
Distance from Earth 1,027.44 light-years
Earth Similarity Index 0.322
Travel time at Voyager 1 speed 18,118,852 years

1 sibling around K2-195

K2-195 b 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
K2-195 b this	Sub-Neptune	3.13	9.96	15.853	720	2018
K2-195 c	Sub-Neptune	2.58	7.16	28.483	—	2018

K2-195 b Planet Profile

Physical Specs

Radius

3.13 R⊕

Radius (Jupiter)

0.279 R♃

Mass

9.96 M⊕

Mass (Jupiter)

0.031 M♃

Density

1.78 g/cm³

Surface Gravity

1.02 g (Earth)

Classification

Planet Type

Sub-Neptune

ESI Score 0.322

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

#406of 1978

top 20.5%

This planet

3.13R⊕

Sub-Neptune median

2.71R⊕

Nearest-size peers

Kepler-1546 b 3.13 R⊕ Kepler-104 c 3.13 R⊕ Kepler-146 c 3.13 R⊕

Metric	Earth	K2-195 b	Jupiter
Radius (R⊕)	1.00	3.13	11.21
Mass (M⊕)	1.00	9.96	317.83
Density (g/cm³)	5.51	1.78	1.33
Surface Gravity (g)	1.00	1.02	2.53
Insolation (S⊕)	1.00	—	0.037

Star Catalogue Identifiers

TIC

TIC 178941218

Gaia DR2

Gaia DR2 3624969886932157568

Gaia DR3

Gaia DR3 3624969886932157568

System

K2-195

Percentile among Sub-Neptune cohort

Radius 3.130 R⊕ · percentile 79 / cohort 1978

Mass 9.960 M⊕ · percentile 72 / cohort 1978

Orbital period 15.85 d · percentile 53 / cohort 1946

Distance 315.01 pc · percentile 36 / cohort 1975

ESI 0.322 · percentile 33 / cohort 1978

Orbit & Habitability

Orbital Dynamics

Period

15.853 days

Semi-major axis

0.1208 AU

Eccentricity

—

Inclination

89.04 °

Year Length

A year here lasts approximately 15.85 Earth days (4.3% of a terrestrial year) at a mean orbital distance of 0.1208 AU.

Transit Fingerprint

Depth

0.112 %

Duration

4.841 h

Impact parameter b

0.340

Rp / R★

0.029000

Transit midpoint (BJD)

2,457,225.0456

Photometric dip

Transit produces a flux drop of 1,118 ppm lasting ≈ 4.84 h.

Extended Orbital Architecture

Planet / star radius ratio

0.029000

Semi-major axis / stellar radius

24.330

Impact parameter (b)

0.340

Transit mid-time (BJD)

2,457,225.0456

Angular separation (arcsec)

0.38300

Eq. Temperature

720K

(447 °C)

Insolation (S⊕)

—

Earth = 1.00

Earth Similarity (ESI)

0.322

0 = alien, 1 = Earth-identical

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

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: K2-195

Spectral Class

G-type yellow (Sun-like)

Effective Temperature

5,713 K — cooler than the Sun (5,778 K)

Estimated Age

—

Stellar Radius

0.990 R☉

Stellar Mass

0.940 M☉

Metallicity [Fe/H]

-0.10

Extended Stellar Properties

Surface gravity (log g)

4.420 dex

Stellar density

1.090 g/cm³

Systemic radial velocity

-14.45 km/s

Metallicity ratio

[Fe/H]

Distance

315.01 parsec

Light-years 1,027.44 ly

V-band magnitude

12.52 mag

Voyager-speed travel 18,118,852 yr

Multi-band Host Photometry — 12 bands

Astrometric Data

Parallax

3.146 mas

Total Proper Motion

12.604 mas/yr

PM Right Ascension

1.00 mas/yr

PM Declination

-12.56 mas/yr

Galactic Cartesian (pc)

x = -0.930 · y = -0.336 · z = -0.148

Equatorial (J2000)

RA 199.83152° · Dec -8.50954°

Galactic ℓ, b

314.639° · 53.727°

Ecliptic λ, β

201.508° · -0.132°

HTM-20 index

-357247484