Key parameters at a glance

A radius of 2.12 Earth radii
A mass of 5.14 Earth masses
Surface gravity around 1.14 g
An orbital period of 18.458 days
Semi-major axis 0.1301 AU
Equilibrium temperature 632 K (359 °C)
Distance from Earth 1,964.03 light-years
Earth Similarity Index 0.425
Travel time at Voyager 1 speed 34,635,723 years

Kepler-877 b Planet Profile

Physical Specs

Radius

2.12 R⊕

Radius (Jupiter)

0.189 R♃

Mass

5.14 M⊕

Mass (Jupiter)

0.016 M♃

Density

2.96 g/cm³

Surface Gravity

1.14 g (Earth)

Classification

Planet Type

Sub-Neptune

ESI Score 0.425

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

#1782of 1978

top 90.0%

This planet

2.12R⊕

Sub-Neptune median

2.71R⊕

Nearest-size peers

Kepler-161 b 2.12 R⊕ Kepler-158 b 2.12 R⊕ HD 97658 b 2.12 R⊕

Metric	Earth	Kepler-877 b	Jupiter
Radius (R⊕)	1.00	2.12	11.21
Mass (M⊕)	1.00	5.14	317.83
Density (g/cm³)	5.51	2.96	1.33
Surface Gravity (g)	1.00	1.14	2.53
Insolation (S⊕)	1.00	37.81	0.037

Star Catalogue Identifiers

TIC

TIC 159175206

Gaia DR2

Gaia DR2 2127712955764258048

Gaia DR3

Gaia DR3 2127712955764258048

System

Kepler-877

Percentile among Sub-Neptune cohort

Radius 2.120 R⊕ · percentile 9 / cohort 1978

Mass 5.140 M⊕ · percentile 10 / cohort 1978

Orbital period 18.46 d · percentile 59 / cohort 1946

Distance 602.18 pc · percentile 53 / cohort 1975

ESI 0.425 · percentile 57 / cohort 1978

Orbit & Habitability

Orbital Dynamics

Period

18.458 days

Semi-major axis

0.1301 AU

Eccentricity

0.000

Inclination

88.09 °

Year Length

A year here lasts approximately 18.46 Earth days (5.1% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.1301 AU.

Transit Fingerprint

Depth

0.054 %

Duration

3.308 h

Impact parameter b

0.790

Rp / R★

0.024361

Transit midpoint (BJD)

2,454,971.1646

Photometric dip

Transit produces a flux drop of 535 ppm lasting ≈ 3.31 h.

Extended Orbital Architecture

Planet / star radius ratio

0.024361

Semi-major axis / stellar radius

25.000

Impact parameter (b)

0.790

Transit mid-time (BJD)

2,454,971.1646

Angular separation (arcsec)

0.21600

Eq. Temperature

632K

(359 °C)

Insolation (S⊕)

37.81

Earth = 1.00

Earth Similarity (ESI)

0.425

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-877

Spectral Class

G-type yellow (Sun-like)

Effective Temperature

5,261 K — cooler than the Sun (5,778 K)

Estimated Age

4.57 Gyr — younger than the Sun (4.6 Gyr)

Stellar Radius

0.810 R☉

Stellar Mass

0.850 M☉

Metallicity [Fe/H]

-0.06

Extended Stellar Properties

Surface gravity (log g)

4.560 dex

Stellar density

1.197 g/cm³

Metallicity ratio

[Fe/H]

Distance

602.18 parsec

Light-years 1,964.03 ly

V-band magnitude

14.74 mag

Voyager-speed travel 34,635,723 yr

Multi-band Host Photometry — 16 bands

Astrometric Data

Parallax

0.779 mas

Total Proper Motion

18.102 mas/yr

PM Right Ascension

-7.42 mas/yr

PM Declination

16.51 mas/yr

Galactic Cartesian (pc)

x = 0.234 · y = -0.647 · z = 0.726

Equatorial (J2000)

RA 289.85910° · Dec 46.52274°

Galactic ℓ, b

77.979° · 14.848°

Ecliptic λ, β

307.452° · 67.397°

HTM-20 index

1800583137