Key parameters at a glance

A radius of 2.56 Earth radii
A mass of 7.08 Earth masses
Surface gravity around 1.08 g
An orbital period of 1.443 days
Semi-major axis 0.0284 AU
Equilibrium temperature 2,700 K (2427 °C)
Distance from Earth 1,868.87 light-years
Earth Similarity Index 0.077
Travel time at Voyager 1 speed 32,957,589 years

Kepler-1171 b Planet Profile

Physical Specs

Radius

2.56 R⊕

Radius (Jupiter)

0.228 R♃

Mass

7.08 M⊕

Mass (Jupiter)

0.022 M♃

Density

2.32 g/cm³

Surface Gravity

1.08 g (Earth)

Classification

Planet Type

Sub-Neptune

ESI Score 0.077

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

#1092of 1978

top 55.2%

This planet

2.56R⊕

Sub-Neptune median

2.71R⊕

Nearest-size peers

Kepler-171 c 2.56 R⊕ Kepler-640 b 2.56 R⊕ Kepler-175 b 2.56 R⊕

Metric	Earth	Kepler-1171 b	Jupiter
Radius (R⊕)	1.00	2.56	11.21
Mass (M⊕)	1.00	7.08	317.83
Density (g/cm³)	5.51	2.32	1.33
Surface Gravity (g)	1.00	1.08	2.53
Insolation (S⊕)	1.00	10,171.01	0.037

Star Catalogue Identifiers

TIC

TIC 138888759

Gaia DR2

Gaia DR2 2052136752727511552

Gaia DR3

Gaia DR3 2052136752727511552

System

Kepler-1171

Percentile among Sub-Neptune cohort

Radius 2.560 R⊕ · percentile 44 / cohort 1978

Mass 7.080 M⊕ · percentile 41 / cohort 1978

Orbital period 1.44 d · percentile 1 / cohort 1946

Distance 573.00 pc · percentile 51 / cohort 1975

ESI 0.077 · percentile 0 / cohort 1978

Orbit & Habitability

Orbital Dynamics

Period

1.443 days

Semi-major axis

0.0284 AU

Eccentricity

0.000

Inclination

86.82 °

Year Length

A year here lasts approximately 1.44 Earth days (0.4% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.0284 AU.

Transit Fingerprint

Depth

0.017 %

Duration

3.015 h

Impact parameter b

0.673

Rp / R★

0.012258

Transit midpoint (BJD)

2,454,967.0722

Photometric dip

Transit produces a flux drop of 175 ppm lasting ≈ 3.02 h.

Extended Orbital Architecture

Planet / star radius ratio

0.012258

Semi-major axis / stellar radius

3.727

Impact parameter (b)

0.673

Transit mid-time (BJD)

2,454,967.0722

Angular separation (arcsec)

0.04960

Eq. Temperature

2,700K

(2427 °C)

Insolation (S⊕)

10,171.01

Earth = 1.00

Earth Similarity (ESI)

0.077

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-1171

Spectral Class

F-type yellow-white

Effective Temperature

7,044 K — hotter than the Sun (5,778 K)

Estimated Age

1.35 Gyr — younger than the Sun (4.6 Gyr)

Stellar Radius

1.950 R☉

Stellar Mass

1.580 M☉

Metallicity [Fe/H]

-0.01

Extended Stellar Properties

Surface gravity (log g)

4.050 dex

Stellar density

0.475 g/cm³

Metallicity ratio

[Fe/H]

Distance

573.00 parsec

Light-years 1,868.87 ly

V-band magnitude

11.65 mag

Voyager-speed travel 32,957,589 yr

Multi-band Host Photometry — 16 bands

Astrometric Data

Parallax

1.717 mas

Total Proper Motion

4.055 mas/yr

PM Right Ascension

1.44 mas/yr

PM Declination

3.79 mas/yr

Galactic Cartesian (pc)

x = 0.330 · y = -0.709 · z = 0.624

Equatorial (J2000)

RA 294.95893° · Dec 38.59160°

Galactic ℓ, b

72.425° · 7.968°

Ecliptic λ, β

309.361° · 58.668°

HTM-20 index

-1895329319