Key parameters at a glance

A radius of 1.47 Earth radii
A mass of 2.77 Earth masses
Surface gravity around 1.28 g
An orbital period of 0.962 days
Semi-major axis 0.0158 AU
Equilibrium temperature 1,077 K (804 °C)
Distance from Earth 295.33 light-years
Earth Similarity Index 0.277
Travel time at Voyager 1 speed 5,208,185 years
Almost certainly tidally locked to its host star given the close orbit

K2-147 b Planet Profile

Physical Specs

Radius

1.47 R⊕

Radius (Jupiter)

0.131 R♃

Mass

2.77 M⊕

Mass (Jupiter)

0.009 M♃

Density

4.76 g/cm³

Surface Gravity

1.28 g (Earth)

Classification

Planet Type

Super-Earth

ESI Score 0.277

HZ Position Inner

Controversial No

Discovery

Year 2018

Method Transit

Facility K2

Telescope 0.95 m Kepler Telescope

Size rank in cohort

Rank by radius

#800of 1176

top 67.9%

This planet

1.47R⊕

Super-Earth median

1.60R⊕

Nearest-size peers

Kepler-1756 b 1.47 R⊕ Kepler-1901 b 1.47 R⊕ Kepler-1826 b 1.48 R⊕

Metric	Earth	K2-147 b	Jupiter
Radius (R⊕)	1.00	1.47	11.21
Mass (M⊕)	1.00	2.77	317.83
Density (g/cm³)	5.51	4.76	1.33
Surface Gravity (g)	1.00	1.28	2.53
Insolation (S⊕)	1.00	200.10	0.037

Star Catalogue Identifiers

TIC

TIC 398275886

Gaia DR2

Gaia DR2 6764974194470777600

Gaia DR3

Gaia DR3 6764974194470777600

System

K2-147

Percentile among Super-Earth cohort

Radius 1.473 R⊕ · percentile 32 / cohort 1176

Mass 2.770 M⊕ · percentile 30 / cohort 1176

Orbital period 0.96 d · percentile 5 / cohort 1164

Distance 90.55 pc · percentile 16 / cohort 1171

ESI 0.277 · percentile 31 / cohort 1176

Orbit & Habitability

Orbital Dynamics

Period

0.962 days

Semi-major axis

0.0158 AU

Eccentricity

0.380

Inclination

83.60 °

Year Length

A year here lasts roughly 23.1 hours long on a highly eccentric trajectory at a mean orbital distance of 0.0158 AU.

Transit Fingerprint

Depth

0.055 %

Duration

0.902 h

Impact parameter b

0.500

Rp / R★

0.023400

Transit midpoint (BJD)

2,457,343.3091

Photometric dip

Transit produces a flux drop of 545 ppm lasting ≈ 0.90 h.

Extended Orbital Architecture

Planet / star radius ratio

0.023400

Semi-major axis / stellar radius

5.860

Impact parameter (b)

0.500

Transit mid-time (BJD)

2,457,343.3091

Long. of periastron (ω)

40.00°

Angular separation (arcsec)

0.17400

Eq. Temperature

1,077K

(804 °C)

Insolation (S⊕)

200.10

Earth = 1.00

Earth Similarity (ESI)

0.277

0 = alien, 1 = Earth-identical

Inside the inner HZ boundary (too hot for liquid water) — the dayside is scorched. Close-orbiting tidally-locked around a cool host.

Discovery Paper

Primary reference

Hirano et al. 2018

Instrument

Kepler CCD Array

Publication

2018-03

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: K2-147

Spectral Class

M-type red dwarf

Effective Temperature

3,690 K — cooler than the Sun (5,778 K)

Estimated Age

—

Stellar Radius

0.578 R☉

Stellar Mass

0.563 M☉

Metallicity [Fe/H]

-0.02

Extended Stellar Properties

Surface gravity (log g)

4.665 dex

Stellar density

4.110 g/cm³

Systemic radial velocity

-24.15 km/s

Metallicity ratio

[Fe/H]

Distance

90.55 parsec

Light-years 295.33 ly

V-band magnitude

14.04 mag

Voyager-speed travel 5,208,185 yr

Multi-band Host Photometry — 12 bands

Astrometric Data

Parallax

11.015 mas

Total Proper Motion

150.843 mas/yr

PM Right Ascension

-31.43 mas/yr

PM Declination

-147.53 mas/yr

Galactic Cartesian (pc)

x = 0.355 · y = -0.804 · z = -0.477

Equatorial (J2000)

RA 293.83303° · Dec -28.49848°

Galactic ℓ, b

10.944° · -21.497°

Ecliptic λ, β

290.950° · -6.776°

HTM-20 index

1788834709