Key parameters at a glance

A radius of 2.62 Earth radii
A mass of 7.37 Earth masses
Surface gravity around 1.07 g
An orbital period of 26.853 days
Semi-major axis 0.1620 AU
Equilibrium temperature 544 K (271 °C)
Distance from Earth 1,855.02 light-years
Earth Similarity Index 0.452
Travel time at Voyager 1 speed 32,713,197 years

Kepler-977 b Planet Profile

Physical Specs

Radius

2.62 R⊕

Radius (Jupiter)

0.234 R♃

Mass

7.37 M⊕

Mass (Jupiter)

0.023 M♃

Density

2.25 g/cm³

Surface Gravity

1.07 g (Earth)

Classification

Planet Type

Sub-Neptune

ESI Score 0.452

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

#989of 1978

top 49.9%

This planet

2.62R⊕

Sub-Neptune median

2.71R⊕

Nearest-size peers

TOI-815 c 2.62 R⊕ K2-337 b 2.62 R⊕ Kepler-450 c 2.62 R⊕

Metric	Earth	Kepler-977 b	Jupiter
Radius (R⊕)	1.00	2.62	11.21
Mass (M⊕)	1.00	7.37	317.83
Density (g/cm³)	5.51	2.25	1.33
Surface Gravity (g)	1.00	1.07	2.53
Insolation (S⊕)	1.00	13.96	0.037

Star Catalogue Identifiers

TIC

TIC 159768168

Gaia DR2

Gaia DR2 2101760014585798528

Gaia DR3

Gaia DR3 2101760014585798528

System

Kepler-977

Percentile among Sub-Neptune cohort

Radius 2.620 R⊕ · percentile 50 / cohort 1978

Mass 7.370 M⊕ · percentile 46 / cohort 1978

Orbital period 26.85 d · percentile 71 / cohort 1946

Distance 568.75 pc · percentile 51 / cohort 1975

ESI 0.452 · percentile 63 / cohort 1978

Orbit & Habitability

Orbital Dynamics

Period

26.853 days

Semi-major axis

0.1620 AU

Eccentricity

0.000

Inclination

89.99 °

Year Length

A year here lasts approximately 26.85 Earth days (7.4% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.1620 AU.

Transit Fingerprint

Depth

0.100 %

Duration

4.506 h

Impact parameter b

0.010

Rp / R★

0.029126

Transit midpoint (BJD)

2,454,976.3112

Photometric dip

Transit produces a flux drop of 1,004 ppm lasting ≈ 4.51 h.

Extended Orbital Architecture

Planet / star radius ratio

0.029126

Semi-major axis / stellar radius

47.326

Impact parameter (b)

0.010

Transit mid-time (BJD)

2,454,976.3112

Angular separation (arcsec)

0.28500

Eq. Temperature

544K

(271 °C)

Insolation (S⊕)

13.96

Earth = 1.00

Earth Similarity (ESI)

0.452

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-977

Spectral Class

G-type yellow (Sun-like)

Effective Temperature

5,315 K — cooler than the Sun (5,778 K)

Estimated Age

4.57 Gyr — younger than the Sun (4.6 Gyr)

Stellar Radius

0.830 R☉

Stellar Mass

0.870 M☉

Metallicity [Fe/H]

-0.01

Extended Stellar Properties

Surface gravity (log g)

4.550 dex

Stellar density

2.045 g/cm³

Metallicity ratio

[Fe/H]

Distance

568.75 parsec

Light-years 1,855.02 ly

V-band magnitude

14.75 mag

Voyager-speed travel 32,713,197 yr

Multi-band Host Photometry — 16 bands

Astrometric Data

Parallax

1.730 mas

Total Proper Motion

24.538 mas/yr

PM Right Ascension

-3.61 mas/yr

PM Declination

-24.27 mas/yr

Galactic Cartesian (pc)

x = 0.271 · y = -0.689 · z = 0.672

Equatorial (J2000)

RA 291.51620° · Dec 42.24807°

Galactic ℓ, b

74.508° · 11.971°

Ecliptic λ, β

306.685° · 62.973°

HTM-20 index

-375291148