Key parameters at a glance

A radius of 12.44 Earth radii
An orbital period of 3.905 days
Semi-major axis 0.0477 AU
Equilibrium temperature 1,046 K (773 °C)
Distance from Earth 2,983.35 light-years
Earth Similarity Index 0.056
Travel time at Voyager 1 speed 52,611,298 years

KOI-217 b Planet Profile

Physical Specs

Radius

12.44 R⊕

Radius (Jupiter)

1.110 R♃

Mass

— M⊕

Mass (Jupiter)

— M♃

Density

— g/cm³

Surface Gravity

— g (Earth)

Classification

Planet Type

Gas Giant

ESI Score 0.056

HZ Position Inner

Controversial No

Discovery

Year 2010

Method Transit

Facility Kepler

Telescope 0.95 m Kepler Telescope

Size rank in cohort

Rank by radius

#1285of 1771

top 72.5%

This planet

12.44R⊕

Gas Giant median

13.52R⊕

Nearest-size peers

KELT-1 b 12.44 R⊕ HR 2562 b 12.44 R⊕ WASP-11 b 12.44 R⊕

Metric	Earth	KOI-217 b	Jupiter
Radius (R⊕)	1.00	12.44	11.21
Mass (M⊕)	1.00	—	317.83
Density (g/cm³)	5.51	—	1.33
Surface Gravity (g)	1.00	—	2.53
Insolation (S⊕)	1.00	272.03	0.037

Star Catalogue Identifiers

TIC

TIC 271354351

Gaia DR2

Gaia DR2 2080095679848047872

Gaia DR3

Gaia DR3 2080095684150253952

System

KOI-217

Percentile among Gas Giant cohort

Radius 12.442 R⊕ · percentile 27 / cohort 1771

Orbital period 3.91 d · percentile 28 / cohort 1533

Distance 914.70 pc · percentile 85 / cohort 1759

ESI 0.056 · percentile 7 / cohort 1771

Orbit & Habitability

Orbital Dynamics

Period

3.905 days

Semi-major axis

0.0477 AU

Eccentricity

0.000

Inclination

89.80 °

Year Length

A year here lasts approximately 3.91 Earth days (1.1% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.0477 AU.

Transit Fingerprint

Depth

1.756 %

Duration

2.855 h

Impact parameter b

0.005

Rp / R★

0.135684

Transit midpoint (BJD)

2,454,966.4140

Photometric dip

Transit produces a flux drop of 17,560 ppm lasting ≈ 2.86 h.

Extended Orbital Architecture

Planet / star radius ratio

0.135684

Semi-major axis / stellar radius

11.897

Impact parameter (b)

0.005

Transit mid-time (BJD)

2,454,966.4140

Angular separation (arcsec)

0.05210

Eq. Temperature

1,046K

(773 °C)

Insolation (S⊕)

272.03

Earth = 1.00

Earth Similarity (ESI)

0.056

0 = alien, 1 = Earth-identical

Inside the inner HZ boundary (too hot for liquid water) — the dayside is scorched.

Detection Signatures

Transit photometry

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

Transit timing variations

Gravitational interactions from neighbours have been detected.

Discovery Paper

Primary reference

Howell et al. 2010

Instrument

Kepler CCD Array

Publication

2010-12

Observation locale

Space

Discovery cohort

Planets confirmed in 2010 at Kepler (11 shown).

Kepler-11 g · Sub-Neptune Kepler-11 f · Sub-Neptune Kepler-11 d · Sub-Neptune Kepler-11 e · Neptune-like Kepler-11 b · Super-Earth Kepler-9 c · Neptune-like Kepler-11 c · Sub-Neptune Kepler-9 b · Neptune-like Kepler-9 d · Super-Earth Kepler-40 b · Gas Giant Kepler-8 b · Gas Giant

Host System: KOI-217

Spectral Class

G-type yellow (Sun-like)

Effective Temperature

5,545 K — cooler than the Sun (5,778 K)

Estimated Age

1.70 Gyr — younger than the Sun (4.6 Gyr)

Stellar Radius

0.860 R☉

Stellar Mass

0.950 M☉

Metallicity [Fe/H]

0.12

Extended Stellar Properties

Surface gravity (log g)

4.530 dex

Stellar density

2.082 g/cm³

Metallicity ratio

[Fe/H]

Distance

914.70 parsec

Light-years 2,983.35 ly

V-band magnitude

15.26 mag

Voyager-speed travel 52,611,298 yr

Multi-band Host Photometry — 16 bands

Astrometric Data

Parallax

1.065 mas

Total Proper Motion

2.577 mas/yr

PM Right Ascension

-2.34 mas/yr

PM Declination

-1.07 mas/yr

Galactic Cartesian (pc)

x = 0.291 · y = -0.627 · z = 0.723

Equatorial (J2000)

RA 294.86547° · Dec 46.28581°

Galactic ℓ, b

79.292° · 11.633°

Ecliptic λ, β

315.277° · 65.861°

HTM-20 index

-1221999300