Key parameters at a glance

A radius of 2.57 Earth radii
A mass of 7.13 Earth masses
Surface gravity around 1.08 g
An orbital period of 7.173 days
Semi-major axis 0.0699 AU
Equilibrium temperature 886 K (613 °C)
Distance from Earth 1,325.02 light-years
Earth Similarity Index 0.282
Travel time at Voyager 1 speed 23,366,758 years

K2-248 b Planet Profile

Physical Specs

Radius

2.57 R⊕

Radius (Jupiter)

0.229 R♃

Mass

7.13 M⊕

Mass (Jupiter)

0.022 M♃

Density

2.31 g/cm³

Surface Gravity

1.08 g (Earth)

Classification

Planet Type

Sub-Neptune

ESI Score 0.282

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

#1074of 1978

top 54.2%

This planet

2.57R⊕

Sub-Neptune median

2.71R⊕

Nearest-size peers

Kepler-1549 b 2.57 R⊕ Kepler-245 b 2.57 R⊕ Kepler-313 c 2.57 R⊕

Metric	Earth	K2-248 b	Jupiter
Radius (R⊕)	1.00	2.57	11.21
Mass (M⊕)	1.00	7.13	317.83
Density (g/cm³)	5.51	2.31	1.33
Surface Gravity (g)	1.00	1.08	2.53
Insolation (S⊕)	1.00	—	0.037

Star Catalogue Identifiers

TIC

TIC 176869982

Gaia DR2

Gaia DR2 3582057258065666816

Gaia DR3

Gaia DR3 3582057258065666816

System

K2-248

Percentile among Sub-Neptune cohort

Radius 2.570 R⊕ · percentile 45 / cohort 1978

Mass 7.130 M⊕ · percentile 42 / cohort 1978

Orbital period 7.17 d · percentile 23 / cohort 1946

Distance 406.25 pc · percentile 41 / cohort 1975

ESI 0.282 · percentile 24 / cohort 1978

Orbit & Habitability

Orbital Dynamics

Period

7.173 days

Semi-major axis

0.0699 AU

Eccentricity

—

Inclination

— °

Year Length

A year here lasts approximately 7.17 Earth days (2.0% of a terrestrial year) at a mean orbital distance of 0.0699 AU.

Transit Fingerprint

Depth

0.070 %

Duration

2.800 h

Impact parameter b

0.400

Rp / R★

0.025500

Transit midpoint (BJD)

2,457,588.1042

Photometric dip

Transit produces a flux drop of 700 ppm lasting ≈ 2.80 h.

Extended Orbital Architecture

Planet / star radius ratio

0.025500

Semi-major axis / stellar radius

16.200

Impact parameter (b)

0.400

Transit mid-time (BJD)

2,457,588.1042

Angular separation (arcsec)

0.17200

Eq. Temperature

886K

(613 °C)

Insolation (S⊕)

—

Earth = 1.00

Earth Similarity (ESI)

0.282

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: K2-248

Spectral Class

G-type yellow (Sun-like)

Effective Temperature

5,528 K — cooler than the Sun (5,778 K)

Estimated Age

—

Stellar Radius

0.920 R☉

Stellar Mass

0.880 M☉

Metallicity [Fe/H]

-0.10

Extended Stellar Properties

Surface gravity (log g)

4.450 dex

Stellar density

1.826 g/cm³

Rotational v·sin i

2.60 km/s

Metallicity ratio

[Fe/H]

Distance

406.25 parsec

Light-years 1,325.02 ly

V-band magnitude

13.50 mag

Voyager-speed travel 23,366,758 yr

Multi-band Host Photometry — 12 bands

Astrometric Data

Parallax

2.433 mas

Total Proper Motion

37.011 mas/yr

PM Right Ascension

19.56 mas/yr

PM Declination

-31.42 mas/yr

Galactic Cartesian (pc)

x = -0.985 · y = -0.048 · z = -0.164

Equatorial (J2000)

RA 182.81733° · Dec -9.41417°

Galactic ℓ, b

286.638° · 52.182°

Ecliptic λ, β

186.340° · -7.515°

HTM-20 index

702139182