Confirmed Exoplanet Discovered 2018

EPIC 248847494 b

A gas giant orbiting the k-type orange EPIC 248847494, located approximately 1,800.0 light-years from Earth.

Key parameters at a glance

  • A radius of 12.44 Earth radii
  • A mass of 4,131.79 Earth masses
  • Surface gravity around 26.69 g
  • An orbital period of 3,650.000 days
  • Semi-major axis 4.5000 AU
  • Equilibrium temperature 183 K (-90 °C)
  • Distance from Earth 1,800.01 light-years
  • Earth Similarity Index 0.257
  • Travel time at Voyager 1 speed 31,743,162 years

EPIC 248847494 b Planet Profile

Physical Specs

Radius
12.44 R⊕
Radius (Jupiter)
1.110 R♃
Mass
4,131.79 M⊕
Mass (Jupiter)
13.000 M♃
Density
g/cm³
Surface Gravity
26.69 g (Earth)

Classification

Planet Type

Gas Giant

ESI Score 0.257
HZ Position Outer
Controversial No

Discovery

Year 2018
Method Transit
Facility K2
Telescope 0.95 m Kepler Telescope

Size rank in cohort

Rank by radius

#1287of 1771

top 72.6%

This planet

12.44R⊕

Gas Giant median

13.52R⊕

Nearest-size peers

Metric Earth EPIC 248847494 b Jupiter
Radius (R⊕)1.0012.4411.21
Mass (M⊕)1.004,131.79317.83
Density (g/cm³)5.511.33
Surface Gravity (g)1.0026.692.53
Insolation (S⊕)1.000.190.037

Alternative Mass Estimates

Method Value Interpretation
Best measured mass 4,131.790 M⊕ Direct mass measurement (not derived).

Star Catalogue Identifiers

TIC

TIC 392876254

Gaia DR2

Gaia DR2 3882879683758393344

Gaia DR3

Gaia DR3 3882879683758393344

System

EPIC 248847494

Percentile among Gas Giant cohort

Radius 12.442 R⊕ · percentile 27 / cohort 1771
Mass 4,131.790 M⊕ · percentile 92 / cohort 1747
Orbital period 3,650.00 d · percentile 90 / cohort 1533
Distance 551.89 pc · percentile 77 / cohort 1759
ESI 0.257 · percentile 47 / cohort 1771

Orbit & Habitability

Orbital Dynamics

Period
3,650.000 days
Semi-major axis
4.5000 AU
Eccentricity
0.000
Inclination
89.87 °

Year Length

A year here lasts about 9.99 Earth years on a nearly circular orbit at a mean orbital distance of 4.5000 AU.

Transit Fingerprint

Depth

0.180 %

Duration

53.600 h

Impact parameter b

0.790

Rp / R★

0.042000

Transit midpoint (BJD)

2,457,967.1700

Photometric dip

Transit produces a flux drop of 1,800 ppm lasting ≈ 53.60 h.

Extended Orbital Architecture

Planet / star radius ratio

0.042000

Impact parameter (b)

0.790

Transit mid-time (BJD)

2,457,967.1700

Angular separation (arcsec)

8.15000

Eq. Temperature

183K

(-90 °C)

Insolation (S⊕)

0.19

Earth = 1.00

Earth Similarity (ESI)

0.257

0 = alien, 1 = Earth-identical

Beyond the outer HZ boundary (too cold) — surface water would be frozen.

Detection Signatures

Transit photometry

A transit dip has been observed from at least one telescope.

Radial velocity

Stellar wobble has been measured spectroscopically.

Discovery Paper

Primary reference

Giles et al. 2018

Instrument

Kepler CCD Array

Publication

2018-07

Observation locale

Space

Host System: EPIC 248847494

Spectral Class

K-type orange

Effective Temperature

4,898 K — cooler than the Sun (5,778 K)

Estimated Age

Stellar Radius

2.700 R☉

Stellar Mass

0.900 M☉

Metallicity [Fe/H]

-0.23

Extended Stellar Properties

Surface gravity (log g)

3.520 dex

Stellar density

0.064 g/cm³

Systemic radial velocity

30.58 km/s

Metallicity ratio

[Fe/H]

Distance
551.89 parsec
Light-years 1,800.01 ly
V-band magnitude
12.35 mag
Voyager-speed travel 31,743,162 yr

Multi-band Host Photometry — 17 bands

8.315.915.87U13.33B12.35V12.17Gaia12.17Kepler11.59TESS13.24Sloan g12.20Sloan r11.97Sloan i12.42Sloan z10.77J10.24H10.15K10.12W110.18W210.15W38.32W4

Astrometric Data

Parallax

1.783 mas

Total Proper Motion

38.762 mas/yr

PM Right Ascension

-38.74 mas/yr

PM Declination

1.21 mas/yr

Galactic Cartesian (pc)

x = -0.916 · y = 0.345 · z = 0.205

Equatorial (J2000)

RA 159.38908° · Dec 11.84275°

Galactic ℓ, b

232.289° · 55.103°

Ecliptic λ, β

156.527° · 2.938°

HTM-20 index

-1842724207

Similar Worlds

Explore Related Categories