Key parameters at a glance

A radius of 2.79 Earth radii
A mass of 8.20 Earth masses
Surface gravity around 1.05 g
An orbital period of 12.409 days
Semi-major axis 0.1151 AU
Equilibrium temperature 1,061 K (788 °C)
Distance from Earth 1,701.61 light-years
Earth Similarity Index 0.225
Travel time at Voyager 1 speed 30,007,856 years

K2-249 b Planet Profile

Physical Specs

Radius

2.79 R⊕

Radius (Jupiter)

0.249 R♃

Mass

8.20 M⊕

Mass (Jupiter)

0.026 M♃

Density

2.07 g/cm³

Surface Gravity

1.05 g (Earth)

Classification

Planet Type

Sub-Neptune

ESI Score 0.225

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

#754of 1978

top 38.1%

This planet

2.79R⊕

Sub-Neptune median

2.71R⊕

Nearest-size peers

AU Mic c 2.79 R⊕ Kepler-150 d 2.79 R⊕ Kepler-192 c 2.79 R⊕

Metric	Earth	K2-249 b	Jupiter
Radius (R⊕)	1.00	2.79	11.21
Mass (M⊕)	1.00	8.20	317.83
Density (g/cm³)	5.51	2.07	1.33
Surface Gravity (g)	1.00	1.05	2.53
Insolation (S⊕)	1.00	—	0.037

Star Catalogue Identifiers

TIC

TIC 176910179

Gaia DR2

Gaia DR2 3582098107498270208

Gaia DR3

Gaia DR3 3582098107498270208

System

K2-249

Percentile among Sub-Neptune cohort

Radius 2.790 R⊕ · percentile 61 / cohort 1978

Mass 8.200 M⊕ · percentile 56 / cohort 1978

Orbital period 12.41 d · percentile 43 / cohort 1946

Distance 521.72 pc · percentile 48 / cohort 1975

ESI 0.225 · percentile 11 / cohort 1978

Orbit & Habitability

Orbital Dynamics

Period

12.409 days

Semi-major axis

0.1151 AU

Eccentricity

—

Inclination

— °

Year Length

A year here lasts approximately 12.41 Earth days (3.4% of a terrestrial year) at a mean orbital distance of 0.1151 AU.

Transit Fingerprint

Depth

0.024 %

Duration

5.900 h

Impact parameter b

0.410

Rp / R★

0.016200

Transit midpoint (BJD)

2,457,583.0457

Photometric dip

Transit produces a flux drop of 240 ppm lasting ≈ 5.90 h.

Extended Orbital Architecture

Planet / star radius ratio

0.016200

Semi-major axis / stellar radius

14.500

Impact parameter (b)

0.410

Transit mid-time (BJD)

2,457,583.0457

Angular separation (arcsec)

0.22100

Eq. Temperature

1,061K

(788 °C)

Insolation (S⊕)

—

Earth = 1.00

Earth Similarity (ESI)

0.225

0 = alien, 1 = Earth-identical

Insufficient insolation data — the dayside is scorched.

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: K2-249

Spectral Class

F-type yellow-white

Effective Temperature

6,504 K — hotter than the Sun (5,778 K)

Estimated Age

—

Stellar Radius

1.570 R☉

Stellar Mass

1.320 M☉

Metallicity [Fe/H]

0.04

Extended Stellar Properties

Surface gravity (log g)

4.160 dex

Stellar density

0.317 g/cm³

Systemic radial velocity

-23.71 km/s

Metallicity ratio

[Fe/H]

Distance

521.72 parsec

Light-years 1,701.61 ly

V-band magnitude

12.65 mag

Voyager-speed travel 30,007,856 yr

Multi-band Host Photometry — 12 bands

Astrometric Data

Parallax

1.890 mas

Total Proper Motion

11.454 mas/yr

PM Right Ascension

9.16 mas/yr

PM Declination

-6.88 mas/yr

Galactic Cartesian (pc)

x = -0.986 · y = -0.058 · z = -0.156

Equatorial (J2000)

RA 183.36673° · Dec -8.99523°

Galactic ℓ, b

287.330° · 52.722°

Ecliptic λ, β

186.672° · -6.914°

HTM-20 index

-540342966