Key parameters at a glance

A radius of 2.01 Earth radii
A mass of 4.70 Earth masses
Surface gravity around 1.16 g
An orbital period of 24.946 days
Semi-major axis 0.1817 AU
Equilibrium temperature 801 K (528 °C)
Distance from Earth 870.39 light-years
Earth Similarity Index 0.343
Travel time at Voyager 1 speed 15,349,379 years

1 sibling around K2-243

K2-243 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
K2-243 b	Sub-Neptune	2.17	5.35	11.542	1,035	2018
K2-243 c this	Sub-Neptune	2.01	4.70	24.946	801	2018

K2-243 c Planet Profile

Physical Specs

Radius

2.01 R⊕

Radius (Jupiter)

0.179 R♃

Mass

4.70 M⊕

Mass (Jupiter)

0.015 M♃

Density

3.18 g/cm³

Surface Gravity

1.16 g (Earth)

Classification

Planet Type

Sub-Neptune

ESI Score 0.343

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

#1940of 1978

top 98.0%

This planet

2.01R⊕

Sub-Neptune median

2.71R⊕

Nearest-size peers

Kepler-415 c 2.01 R⊕ Kepler-260 b 2.01 R⊕ Kepler-280 c 2.01 R⊕

Metric	Earth	K2-243 c	Jupiter
Radius (R⊕)	1.00	2.01	11.21
Mass (M⊕)	1.00	4.70	317.83
Density (g/cm³)	5.51	3.18	1.33
Surface Gravity (g)	1.00	1.16	2.53
Insolation (S⊕)	1.00	—	0.037

Star Catalogue Identifiers

TIC

TIC 96199085

Gaia DR2

Gaia DR2 3597570989175080576

Gaia DR3

Gaia DR3 3597570989175080576

System

K2-243

Percentile among Sub-Neptune cohort

Radius 2.010 R⊕ · percentile 1 / cohort 1978

Mass 4.700 M⊕ · percentile 3 / cohort 1978

Orbital period 24.95 d · percentile 69 / cohort 1946

Distance 266.86 pc · percentile 33 / cohort 1975

ESI 0.343 · percentile 39 / cohort 1978

Orbit & Habitability

Orbital Dynamics

Period

24.946 days

Semi-major axis

0.1817 AU

Eccentricity

—

Inclination

— °

Year Length

A year here lasts approximately 24.95 Earth days (6.8% of a terrestrial year) at a mean orbital distance of 0.1817 AU.

Transit Fingerprint

Depth

0.019 %

Duration

5.200 h

Impact parameter b

0.400

Rp / R★

0.013300

Transit midpoint (BJD)

2,457,584.5050

Photometric dip

Transit produces a flux drop of 190 ppm lasting ≈ 5.20 h.

Extended Orbital Architecture

Planet / star radius ratio

0.013300

Semi-major axis / stellar radius

35.600

Impact parameter (b)

0.400

Transit mid-time (BJD)

2,457,584.5050

Angular separation (arcsec)

0.68100

Eq. Temperature

801K

(528 °C)

Insolation (S⊕)

—

Earth = 1.00

Earth Similarity (ESI)

0.343

0 = alien, 1 = Earth-identical

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

Discovery Paper

Primary reference

Livingston et al. 2018

Instrument

Kepler CCD Array

Publication

2018-08

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: K2-243

Spectral Class

F-type yellow-white

Effective Temperature

6,570 K — hotter than the Sun (5,778 K)

Estimated Age

—

Stellar Radius

1.390 R☉

Stellar Mass

1.290 M☉

Metallicity [Fe/H]

-0.03

Extended Stellar Properties

Surface gravity (log g)

4.260 dex

Stellar density

0.352 g/cm³

Systemic radial velocity

5.79 km/s

Metallicity ratio

[Fe/H]

Distance

266.86 parsec

Light-years 870.39 ly

V-band magnitude

10.97 mag

Voyager-speed travel 15,349,379 yr

Multi-band Host Photometry — 12 bands

Astrometric Data

Parallax

3.719 mas

Total Proper Motion

64.447 mas/yr

PM Right Ascension

-61.81 mas/yr

PM Declination

18.24 mas/yr

Galactic Cartesian (pc)

x = -0.996 · y = -0.019 · z = -0.085

Equatorial (J2000)

RA 181.12114° · Dec -4.89914°

Galactic ℓ, b

281.666° · 56.022°

Ecliptic λ, β

182.976° · -4.048°

HTM-20 index

-1970276540