Key parameters at a glance

A radius of 1.66 Earth radii
A mass of 3.39 Earth masses
Surface gravity around 1.23 g
An orbital period of 8.630 days
Semi-major axis 0.0779 AU
Equilibrium temperature 739 K (466 °C)
Distance from Earth 2,926.77 light-years
Earth Similarity Index 0.397
Travel time at Voyager 1 speed 51,613,540 years

Kepler-1291 b Planet Profile

Physical Specs

Radius

1.66 R⊕

Radius (Jupiter)

0.148 R♃

Mass

3.39 M⊕

Mass (Jupiter)

0.011 M♃

Density

4.07 g/cm³

Surface Gravity

1.23 g (Earth)

Classification

Planet Type

Super-Earth

ESI Score 0.397

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

#469of 1176

top 39.8%

This planet

1.66R⊕

Super-Earth median

1.60R⊕

Nearest-size peers

Kepler-379 b 1.66 R⊕ Kepler-1497 b 1.66 R⊕ GJ 357 c 1.66 R⊕

Metric	Earth	Kepler-1291 b	Jupiter
Radius (R⊕)	1.00	1.66	11.21
Mass (M⊕)	1.00	3.39	317.83
Density (g/cm³)	5.51	4.07	1.33
Surface Gravity (g)	1.00	1.23	2.53
Insolation (S⊕)	1.00	62.82	0.037

Star Catalogue Identifiers

TIC

TIC 122063936

Gaia DR2

Gaia DR2 2101249188353780480

Gaia DR3

Gaia DR3 2101249188353780480

System

Kepler-1291

Percentile among Super-Earth cohort

Radius 1.660 R⊕ · percentile 59 / cohort 1176

Mass 3.390 M⊕ · percentile 54 / cohort 1176

Orbital period 8.63 d · percentile 60 / cohort 1164

Distance 897.35 pc · percentile 75 / cohort 1171

ESI 0.397 · percentile 60 / cohort 1176

Orbit & Habitability

Orbital Dynamics

Period

8.630 days

Semi-major axis

0.0779 AU

Eccentricity

0.000

Inclination

88.03 °

Year Length

A year here lasts approximately 8.63 Earth days (2.4% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.0779 AU.

Transit Fingerprint

Depth

0.033 %

Duration

3.131 h

Impact parameter b

0.595

Rp / R★

0.018762

Transit midpoint (BJD)

2,454,972.5825

Photometric dip

Transit produces a flux drop of 326 ppm lasting ≈ 3.13 h.

Extended Orbital Architecture

Planet / star radius ratio

0.018762

Semi-major axis / stellar radius

15.300

Impact parameter (b)

0.595

Transit mid-time (BJD)

2,454,972.5825

Angular separation (arcsec)

0.08680

Eq. Temperature

739K

(466 °C)

Insolation (S⊕)

62.82

Earth = 1.00

Earth Similarity (ESI)

0.397

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

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-1291

Spectral Class

G-type yellow (Sun-like)

Effective Temperature

5,216 K — cooler than the Sun (5,778 K)

Estimated Age

4.90 Gyr — older than the Sun (4.6 Gyr)

Stellar Radius

0.800 R☉

Stellar Mass

0.840 M☉

Metallicity [Fe/H]

-0.04

Extended Stellar Properties

Surface gravity (log g)

4.560 dex

Stellar density

1.456 g/cm³

Metallicity ratio

[Fe/H]

Distance

897.35 parsec

Light-years 2,926.77 ly

V-band magnitude

16.26 mag

Voyager-speed travel 51,613,540 yr

Multi-band Host Photometry — 16 bands

Astrometric Data

Parallax

1.086 mas

Total Proper Motion

17.735 mas/yr

PM Right Ascension

-4.59 mas/yr

PM Declination

-17.13 mas/yr

Galactic Cartesian (pc)

x = 0.254 · y = -0.723 · z = 0.643

Equatorial (J2000)

RA 289.37701° · Dec 40.00108°

Galactic ℓ, b

71.723° · 12.458°

Ecliptic λ, β

301.959° · 61.308°

HTM-20 index

-956280592