Key parameters at a glance

A radius of 1.75 Earth radii
A mass of 3.71 Earth masses
Surface gravity around 1.21 g
An orbital period of 21.069 days
Semi-major axis 0.1418 AU
Equilibrium temperature 638 K (365 °C)
Distance from Earth 694.39 light-years
Earth Similarity Index 0.450
Travel time at Voyager 1 speed 12,245,614 years

K2-244 b Planet Profile

Physical Specs

Radius

1.75 R⊕

Radius (Jupiter)

0.156 R♃

Mass

3.71 M⊕

Mass (Jupiter)

0.012 M♃

Density

3.80 g/cm³

Surface Gravity

1.21 g (Earth)

Classification

Planet Type

Super-Earth

ESI Score 0.450

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

#326of 1176

top 27.6%

This planet

1.75R⊕

Super-Earth median

1.60R⊕

Nearest-size peers

Kepler-301 d 1.75 R⊕ Kepler-1243 b 1.75 R⊕ Kepler-122 f 1.75 R⊕

Metric	Earth	K2-244 b	Jupiter
Radius (R⊕)	1.00	1.75	11.21
Mass (M⊕)	1.00	3.71	317.83
Density (g/cm³)	5.51	3.80	1.33
Surface Gravity (g)	1.00	1.21	2.53
Insolation (S⊕)	1.00	—	0.037

Star Catalogue Identifiers

TIC

TIC 56814628

Gaia DR2

Gaia DR2 3597981377595128704

Gaia DR3

Gaia DR3 3597981377595128704

System

K2-244

Percentile among Super-Earth cohort

Radius 1.750 R⊕ · percentile 71 / cohort 1176

Mass 3.710 M⊕ · percentile 64 / cohort 1176

Orbital period 21.07 d · percentile 86 / cohort 1164

Distance 212.90 pc · percentile 25 / cohort 1171

ESI 0.450 · percentile 67 / cohort 1176

Orbit & Habitability

Orbital Dynamics

Period

21.069 days

Semi-major axis

0.1418 AU

Eccentricity

—

Inclination

89.21 °

Year Length

A year here lasts approximately 21.07 Earth days (5.8% of a terrestrial year) at a mean orbital distance of 0.1418 AU.

Transit Fingerprint

Depth

0.030 %

Duration

3.900 h

Impact parameter b

0.440

Rp / R★

0.017400

Transit midpoint (BJD)

2,457,588.4749

Photometric dip

Transit produces a flux drop of 300 ppm lasting ≈ 3.90 h.

Extended Orbital Architecture

Planet / star radius ratio

0.017400

Semi-major axis / stellar radius

38.300

Impact parameter (b)

0.440

Transit mid-time (BJD)

2,457,588.4749

Angular separation (arcsec)

0.66600

Eq. Temperature

638K

(365 °C)

Insolation (S⊕)

—

Earth = 1.00

Earth Similarity (ESI)

0.450

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: K2-244

Spectral Class

G-type yellow (Sun-like)

Effective Temperature

5,677 K — cooler than the Sun (5,778 K)

Estimated Age

—

Stellar Radius

0.920 R☉

Stellar Mass

0.860 M☉

Metallicity [Fe/H]

-0.29

Extended Stellar Properties

Surface gravity (log g)

4.440 dex

Stellar density

2.115 g/cm³

Systemic radial velocity

-19.25 km/s

Rotational v·sin i

3.69 km/s

Metallicity ratio

[Fe/H]

Distance

212.90 parsec

Light-years 694.39 ly

V-band magnitude

11.78 mag

Voyager-speed travel 12,245,614 yr

Multi-band Host Photometry — 12 bands

Astrometric Data

Parallax

4.669 mas

Total Proper Motion

60.201 mas/yr

PM Right Ascension

-56.87 mas/yr

PM Declination

19.75 mas/yr

Galactic Cartesian (pc)

x = -0.996 · y = -0.060 · z = -0.067

Equatorial (J2000)

RA 183.46865° · Dec -3.83181°

Galactic ℓ, b

285.174° · 57.739°

Ecliptic λ, β

184.701° · -2.138°

HTM-20 index

-88193188