Key parameters at a glance

A radius of 2.60 Earth radii
A mass of 7.27 Earth masses
Surface gravity around 1.08 g
An orbital period of 12.208 days
Semi-major axis 0.0980 AU
Equilibrium temperature 665 K (392 °C)
Distance from Earth 450.15 light-years
Earth Similarity Index 0.375
Travel time at Voyager 1 speed 7,938,465 years

K2-53 b Planet Profile

Physical Specs

Radius

2.60 R⊕

Radius (Jupiter)

0.232 R♃

Mass

7.27 M⊕

Mass (Jupiter)

0.023 M♃

Density

2.27 g/cm³

Surface Gravity

1.08 g (Earth)

Classification

Planet Type

Sub-Neptune

ESI Score 0.375

HZ Position Inner

Controversial No

Discovery

Year 2016

Method Transit

Facility K2

Telescope 0.95 m Kepler Telescope

Size rank in cohort

Rank by radius

#1017of 1978

top 51.4%

This planet

2.60R⊕

Sub-Neptune median

2.71R⊕

Nearest-size peers

K2-155 c 2.60 R⊕ Kepler-84 e 2.60 R⊕ Kepler-115 c 2.60 R⊕

Metric	Earth	K2-53 b	Jupiter
Radius (R⊕)	1.00	2.60	11.21
Mass (M⊕)	1.00	7.27	317.83
Density (g/cm³)	5.51	2.27	1.33
Surface Gravity (g)	1.00	1.08	2.53
Insolation (S⊕)	1.00	52.50	0.037

Star Catalogue Identifiers

TIC

TIC 49652731

Gaia DR2

Gaia DR2 6244643373326639360

Gaia DR3

Gaia DR3 6244643373326639360

System

K2-53

Percentile among Sub-Neptune cohort

Radius 2.600 R⊕ · percentile 48 / cohort 1978

Mass 7.270 M⊕ · percentile 44 / cohort 1978

Orbital period 12.21 d · percentile 42 / cohort 1946

Distance 138.02 pc · percentile 24 / cohort 1975

ESI 0.375 · percentile 47 / cohort 1978

Orbit & Habitability

Orbital Dynamics

Period

12.208 days

Semi-major axis

0.0980 AU

Eccentricity

—

Inclination

89.32 °

Year Length

A year here lasts approximately 12.21 Earth days (3.3% of a terrestrial year) at a mean orbital distance of 0.0980 AU.

Transit Fingerprint

Depth

0.100 %

Duration

3.480 h

Impact parameter b

0.310

Rp / R★

0.030000

Transit midpoint (BJD)

2,456,896.3858

Photometric dip

Transit produces a flux drop of 1,001 ppm lasting ≈ 3.48 h.

Extended Orbital Architecture

Planet / star radius ratio

0.030000

Semi-major axis / stellar radius

26.300

Impact parameter (b)

0.310

Transit mid-time (BJD)

2,456,896.3858

Angular separation (arcsec)

0.71000

Eq. Temperature

665K

(392 °C)

Insolation (S⊕)

52.50

Earth = 1.00

Earth Similarity (ESI)

0.375

0 = alien, 1 = Earth-identical

Inside the inner HZ boundary (too hot for liquid water) — the surface is too hot to retain surface water.

Discovery Paper

Primary reference

Crossfield et al. 2016

Instrument

Kepler CCD Array

Publication

2016-09

Observation locale

Space

Discovery cohort

Planets confirmed in 2016 at K2 (12 shown).

K2-72 d · Rocky Terrestrial K2-72 b · Rocky Terrestrial K2-91 b · Rocky Terrestrial K2-72 c · Rocky Terrestrial K2-102 b · Super-Earth K2-90 c · Super-Earth K2-72 e · Super-Earth K2-83 b · Rocky Terrestrial K2-88 b · Rocky Terrestrial K2-80 c · Super-Earth K2-83 c · Super-Earth K2-65 b · Super-Earth

Host System: K2-53

Spectral Class

G-type yellow (Sun-like)

Effective Temperature

5,263 K — cooler than the Sun (5,778 K)

Estimated Age

—

Stellar Radius

0.807 R☉

Stellar Mass

0.851 M☉

Metallicity [Fe/H]

-0.04

Extended Stellar Properties

Surface gravity (log g)

4.555 dex

Stellar density

2.290 g/cm³

Systemic radial velocity

43.34 km/s

Metallicity ratio

[Fe/H]

Distance

138.02 parsec

Light-years 450.15 ly

V-band magnitude

12.63 mag

Voyager-speed travel 7,938,465 yr

Multi-band Host Photometry — 12 bands

Astrometric Data

Parallax

7.217 mas

Total Proper Motion

38.441 mas/yr

PM Right Ascension

33.49 mas/yr

PM Declination

-18.87 mas/yr

Galactic Cartesian (pc)

x = -0.409 · y = -0.843 · z = -0.349

Equatorial (J2000)

RA 244.14197° · Dec -20.40060°

Galactic ℓ, b

354.632° · 21.273°

Ecliptic λ, β

245.864° · 0.899°

HTM-20 index

-1844557107