Key parameters at a glance

A radius of 6.12 Earth radii
A mass of 31.10 Earth masses
Surface gravity around 0.83 g
An orbital period of 9.283 days
Distance from Earth 2,988.63 light-years
Earth Similarity Index 0.421
Travel time at Voyager 1 speed 52,704,476 years
Almost certainly tidally locked to its host star given the close orbit

K2-161 b Planet Profile

Physical Specs

Radius

6.12 R⊕

Radius (Jupiter)

0.546 R♃

Mass

31.10 M⊕

Mass (Jupiter)

0.098 M♃

Density

0.75 g/cm³

Surface Gravity

0.83 g (Earth)

Classification

Planet Type

Neptune-like

ESI Score 0.421

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

#273of 574

top 47.4%

This planet

6.12R⊕

Neptune-like median

6.39R⊕

Nearest-size peers

Kepler-63 b 6.11 R⊕ Kepler-696 b 6.14 R⊕ Kepler-87 c 6.14 R⊕

Metric	Earth	K2-161 b	Jupiter
Radius (R⊕)	1.00	6.12	11.21
Mass (M⊕)	1.00	31.10	317.83
Density (g/cm³)	5.51	0.75	1.33
Surface Gravity (g)	1.00	0.83	2.53
Insolation (S⊕)	1.00	—	0.037

Star Catalogue Identifiers

TIC

TIC 349445839

Gaia DR2

Gaia DR2 3598019894861833856

Gaia DR3

Gaia DR3 3598019899158204160

System

K2-161

Percentile among Neptune-like cohort

Radius 6.117 R⊕ · percentile 52 / cohort 574

Mass 31.100 M⊕ · percentile 52 / cohort 574

Orbital period 9.28 d · percentile 35 / cohort 524

Distance 916.32 pc · percentile 72 / cohort 572

ESI 0.421 · percentile 77 / cohort 574

Orbit & Habitability

Orbital Dynamics

Period

9.283 days

Semi-major axis

— AU

Eccentricity

—

Inclination

87.25 °

Year Length

A year here lasts approximately 9.28 Earth days (2.5% of a terrestrial year).

Transit Fingerprint

Rp / R★

0.021837

Transit midpoint (BJD)

2,457,587.8476

Eq. Temperature

—

Insolation (S⊕)

—

Earth = 1.00

Earth Similarity (ESI)

0.421

0 = alien, 1 = Earth-identical

Insufficient insolation data. Close-orbiting tidally-locked around a cool host.

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: K2-161

Spectral Class

K-type orange

Effective Temperature

4,972 K — cooler than the Sun (5,778 K)

Estimated Age

—

Stellar Radius

2.568 R☉

Stellar Mass

0.987 M☉

Metallicity [Fe/H]

-0.03

Extended Stellar Properties

Surface gravity (log g)

3.630 dex

Systemic radial velocity

-19.13 km/s

Metallicity ratio

[Fe/H]

Distance

916.32 parsec

Light-years 2,988.63 ly

V-band magnitude

12.72 mag

Voyager-speed travel 52,704,476 yr

Multi-band Host Photometry — 17 bands

Astrometric Data

Parallax

1.063 mas

Total Proper Motion

16.398 mas/yr

PM Right Ascension

-0.38 mas/yr

PM Declination

-16.39 mas/yr

Galactic Cartesian (pc)

x = -0.996 · y = -0.066 · z = -0.061

Equatorial (J2000)

RA 183.79385° · Dec -3.49569°

Galactic ℓ, b

285.592° · 58.150°

Ecliptic λ, β

184.866° · -1.700°

HTM-20 index

-177875041

Similar Worlds

HD 115404 A b

Neptune-like · K-type orange

Radius 6.09 R⊕ · 35.8 ly

HD 85390 b

Neptune-like · K-type orange

Radius 6.16 R⊕ · 109.3 ly

HD 156668 c

Neptune-like · K-type orange

Radius 6.17 R⊕ · 79.4 ly

TOI-4010 d

Neptune-like · K-type orange

Radius 6.18 R⊕ · 578.9 ly

WASP-156 b

Neptune-like · K-type orange

Radius 6.03 R⊕ · 398.1 ly

TIC 365102760 b

Neptune-like · K-type orange

Radius 6.21 R⊕ · 1,811.9 ly

Explore Related Categories

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