Key parameters at a glance

A radius of 2.10 Earth radii
A mass of 5.06 Earth masses
Surface gravity around 1.15 g
An orbital period of 3.276 days
Semi-major axis 0.0454 AU
Equilibrium temperature 1,730 K (1457 °C)
Distance from Earth 3,827.67 light-years
Earth Similarity Index 0.143
Travel time at Voyager 1 speed 67,500,939 years

Kepler-645 b Planet Profile

Physical Specs

Radius

2.10 R⊕

Radius (Jupiter)

0.187 R♃

Mass

5.06 M⊕

Mass (Jupiter)

0.016 M♃

Density

3.00 g/cm³

Surface Gravity

1.15 g (Earth)

Classification

Planet Type

Sub-Neptune

ESI Score 0.143

HZ Position Inner

Controversial No

Discovery

Year 2016

Method Transit

Facility Kepler

Telescope 0.95 m Kepler Telescope

Size rank in cohort

Rank by radius

#1818of 1978

top 91.9%

This planet

2.10R⊕

Sub-Neptune median

2.71R⊕

Nearest-size peers

TOI-5734 b 2.10 R⊕ Kepler-52 b 2.10 R⊕ Kepler-360 c 2.10 R⊕

Metric	Earth	Kepler-645 b	Jupiter
Radius (R⊕)	1.00	2.10	11.21
Mass (M⊕)	1.00	5.06	317.83
Density (g/cm³)	5.51	3.00	1.33
Surface Gravity (g)	1.00	1.15	2.53
Insolation (S⊕)	1.00	1,364.76	0.037

Star Catalogue Identifiers

TIC

TIC 159381747

Gaia DR2

Gaia DR2 2126865575897687168

Gaia DR3

Gaia DR3 2126865575897687168

System

Kepler-645

Percentile among Sub-Neptune cohort

Radius 2.100 R⊕ · percentile 7 / cohort 1978

Mass 5.060 M⊕ · percentile 9 / cohort 1978

Orbital period 3.28 d · percentile 6 / cohort 1946

Distance 1,173.57 pc · percentile 86 / cohort 1975

ESI 0.143 · percentile 2 / cohort 1978

Orbit & Habitability

Orbital Dynamics

Period

3.276 days

Semi-major axis

0.0454 AU

Eccentricity

0.000

Inclination

82.54 °

Year Length

A year here lasts approximately 3.28 Earth days (0.9% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.0454 AU.

Transit Fingerprint

Depth

0.027 %

Duration

2.972 h

Impact parameter b

0.490

Rp / R★

0.015691

Transit midpoint (BJD)

2,455,003.2527

Photometric dip

Transit produces a flux drop of 275 ppm lasting ≈ 2.97 h.

Extended Orbital Architecture

Planet / star radius ratio

0.015691

Semi-major axis / stellar radius

8.492

Impact parameter (b)

0.490

Transit mid-time (BJD)

2,455,003.2527

Angular separation (arcsec)

0.03870

Eq. Temperature

1,730K

(1457 °C)

Insolation (S⊕)

1,364.76

Earth = 1.00

Earth Similarity (ESI)

0.143

0 = alien, 1 = Earth-identical

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

Discovery Paper

Primary reference

Morton et al. 2016

Instrument

Kepler CCD Array

Publication

2016-05

Observation locale

Space

Discovery cohort

Planets confirmed in 2016 at Kepler (12 shown).

Kepler-1512 b · Rocky Terrestrial Kepler-1410 b · Super-Earth Kepler-560 b · Super-Earth Kepler-1389 b · Super-Earth Kepler-1450 b · Super-Earth Kepler-1544 b · Super-Earth Kepler-1459 b · Super-Earth Kepler-1638 b · Super-Earth Kepler-737 b · Super-Earth Kepler-1185 b · Super-Earth Kepler-1178 b · Rocky Terrestrial Kepler-1040 b · Sub-Neptune

Host System: Kepler-645

Spectral Class

F-type yellow-white

Effective Temperature

6,170 K — hotter than the Sun (5,778 K)

Estimated Age

2.95 Gyr — younger than the Sun (4.6 Gyr)

Stellar Radius

1.210 R☉

Stellar Mass

1.130 M☉

Metallicity [Fe/H]

-0.01

Extended Stellar Properties

Surface gravity (log g)

4.330 dex

Stellar density

0.320 g/cm³

Metallicity ratio

[Fe/H]

Distance

1,173.57 parsec

Light-years 3,827.67 ly

V-band magnitude

13.94 mag

Voyager-speed travel 67,500,939 yr

Multi-band Host Photometry — 16 bands

Astrometric Data

Parallax

0.823 mas

Total Proper Motion

1.701 mas/yr

PM Right Ascension

-0.81 mas/yr

PM Declination

-1.49 mas/yr

Galactic Cartesian (pc)

x = 0.250 · y = -0.674 · z = 0.695

Equatorial (J2000)

RA 290.32271° · Dec 44.03586°

Galactic ℓ, b

75.781° · 13.524°

Ecliptic λ, β

306.126° · 64.946°

HTM-20 index

629884767