Key parameters at a glance

A radius of 0.61 Earth radii
A mass of 0.17 Earth masses
Surface gravity around 0.44 g
An orbital period of 0.694 days
Semi-major axis 0.0155 AU
Equilibrium temperature 2,161 K (1888 °C)
Distance from Earth 1,182.72 light-years
Earth Similarity Index 0.114
Travel time at Voyager 1 speed 20,857,207 years

Kepler-1087 b Planet Profile

Physical Specs

Radius

0.61 R⊕

Radius (Jupiter)

0.054 R♃

Mass

0.17 M⊕

Mass (Jupiter)

0.001 M♃

Density

3.99 g/cm³

Surface Gravity

0.44 g (Earth)

Classification

Planet Type

Rocky Terrestrial

ESI Score 0.114

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

#548of 570

top 96.0%

This planet

0.61R⊕

Rocky Terrestrial median

1.01R⊕

Nearest-size peers

KOI-1843.03 0.61 R⊕ K2-89 b 0.62 R⊕ Kepler-1998 b 0.60 R⊕

Metric	Earth	Kepler-1087 b	Jupiter
Radius (R⊕)	1.00	0.61	11.21
Mass (M⊕)	1.00	0.17	317.83
Density (g/cm³)	5.51	3.99	1.33
Surface Gravity (g)	1.00	0.44	2.53
Insolation (S⊕)	1.00	3,496.49	0.037

Star Catalogue Identifiers

TIC

TIC 271353794

Gaia DR2

Gaia DR2 2080070975195117312

Gaia DR3

Gaia DR3 2080070975195117312

System

Kepler-1087

Percentile among Rocky Terrestrial cohort

Radius 0.610 R⊕ · percentile 4 / cohort 570

Mass 0.165 M⊕ · percentile 3 / cohort 570

Orbital period 0.69 d · percentile 6 / cohort 567

Distance 362.62 pc · percentile 48 / cohort 566

ESI 0.114 · percentile 2 / cohort 570

Orbit & Habitability

Orbital Dynamics

Period

0.694 days

Semi-major axis

0.0155 AU

Eccentricity

0.000

Inclination

86.59 °

Year Length

A year here lasts roughly 16.7 hours long on a nearly circular orbit at a mean orbital distance of 0.0155 AU.

Transit Fingerprint

Depth

0.005 %

Duration

1.524 h

Impact parameter b

0.693

Rp / R★

0.006460

Transit midpoint (BJD)

2,454,965.1801

Photometric dip

Transit produces a flux drop of 49 ppm lasting ≈ 1.52 h.

Extended Orbital Architecture

Planet / star radius ratio

0.006460

Semi-major axis / stellar radius

3.548

Impact parameter (b)

0.693

Transit mid-time (BJD)

2,454,965.1801

Angular separation (arcsec)

0.04290

Eq. Temperature

2,161K

(1888 °C)

Insolation (S⊕)

3,496.49

Earth = 1.00

Earth Similarity (ESI)

0.114

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-1087

Spectral Class

G-type yellow (Sun-like)

Effective Temperature

5,589 K — cooler than the Sun (5,778 K)

Estimated Age

3.55 Gyr — younger than the Sun (4.6 Gyr)

Stellar Radius

0.940 R☉

Stellar Mass

0.960 M☉

Metallicity [Fe/H]

0.01

Extended Stellar Properties

Surface gravity (log g)

4.480 dex

Stellar density

1.150 g/cm³

Systemic radial velocity

-41.34 km/s

Metallicity ratio

[Fe/H]

Distance

362.62 parsec

Light-years 1,182.72 ly

V-band magnitude

12.97 mag

Voyager-speed travel 20,857,207 yr

Multi-band Host Photometry — 16 bands

Astrometric Data

Parallax

2.729 mas

Total Proper Motion

15.186 mas/yr

PM Right Ascension

14.33 mas/yr

PM Declination

5.04 mas/yr

Galactic Cartesian (pc)

x = 0.293 · y = -0.630 · z = 0.719

Equatorial (J2000)

RA 294.97893° · Dec 46.00567°

Galactic ℓ, b

79.075° · 11.435°

Ecliptic λ, β

315.174° · 65.573°

HTM-20 index

-1269493332