Key parameters at a glance
- A radius of 5.50 Earth radii
- A mass of 25.90 Earth masses
- Surface gravity around 0.86 g
- An orbital period of 5.907 days
- Semi-major axis 0.0559 AU
- Equilibrium temperature 769 K (496 °C)
- Distance from Earth 2,689.77 light-years
- Earth Similarity Index 0.235
- Travel time at Voyager 1 speed 47,434,081 years
- Almost certainly tidally locked to its host star given the close orbit
Kepler-957 b Planet Profile
Physical Specs
Classification
Planet Type
Neptune-like
Discovery
Size rank in cohort
Rank by radius
#317of 574
top 55.1%
This planet
5.50R⊕
Neptune-like median
6.39R⊕
Nearest-size peers
| Metric | Earth | Kepler-957 b | Jupiter |
|---|---|---|---|
| Radius (R⊕) | 1.00 | 5.50 | 11.21 |
| Mass (M⊕) | 1.00 | 25.90 | 317.83 |
| Density (g/cm³) | 5.51 | 0.86 | 1.33 |
| Surface Gravity (g) | 1.00 | 0.86 | 2.53 |
| Insolation (S⊕) | 1.00 | 124.91 | 0.037 |
Star Catalogue Identifiers
TIC
TIC 267748934
Gaia DR2
Gaia DR2 2129576559253685632
Gaia DR3
Gaia DR3 2129576559253685632
System
Kepler-957
Percentile among Neptune-like cohort
Orbit & Habitability
Orbital Dynamics
Year Length
A year here lasts approximately 5.91 Earth days (1.6% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.0559 AU.
Transit Fingerprint
Depth
0.538 %
Duration
1.086 h
Impact parameter b
0.282
Rp / R★
0.066828
Transit midpoint (BJD)
2,454,966.9347
Photometric dip
Transit produces a flux drop of 5,383 ppm lasting ≈ 1.09 h.
Extended Orbital Architecture
Planet / star radius ratio
0.066828
Semi-major axis / stellar radius
42.750
Impact parameter (b)
0.282
Transit mid-time (BJD)
2,454,966.9347
Angular separation (arcsec)
0.06780
Eq. Temperature
769K
(496 °C)
Insolation (S⊕)
124.91
Earth = 1.00
Earth Similarity (ESI)
0.235
0 = alien, 1 = Earth-identical
Inside the inner HZ boundary (too hot for liquid water) — the surface is too hot to retain surface water. Close-orbiting tidally-locked around a cool host.
Detection Signatures
Transit photometry
A transit dip has been observed from at least one telescope.
Transit timing variations
Gravitational interactions from neighbours have been detected.
Discovery Paper
Primary reference
Morton et al. 2016Instrument
Kepler CCD Array
Publication
2016-05
Observation locale
Space
Discovery cohort
Planets confirmed in 2016 at Kepler (12 shown).
Host System: Kepler-957
Spectral Class
K-type orange
Effective Temperature
4,963 K — cooler than the Sun (5,778 K)
Estimated Age
2.75 Gyr — younger than the Sun (4.6 Gyr)
Stellar Radius
0.750 R☉
Stellar Mass
0.810 M☉
Metallicity [Fe/H]
-0.01
Extended Stellar Properties
Surface gravity (log g)
4.600 dex
Stellar density
42.355 g/cm³
Metallicity ratio
[Fe/H]
Multi-band Host Photometry — 16 bands
Astrometric Data
Parallax
1.184 mas
Total Proper Motion
4.325 mas/yr
PM Right Ascension
2.91 mas/yr
PM Declination
-3.20 mas/yr
Galactic Cartesian (pc)
x = 0.227 · y = -0.618 · z = 0.753
Equatorial (J2000)
RA 290.15636° · Dec 48.81897°
Galactic ℓ, b
80.240° · 15.590°
Ecliptic λ, β
310.276° · 69.455°
HTM-20 index
357402524
Similar Worlds
HD 99492 b
Neptune-like · K-type orange
Radius 5.44 R⊕ · 59.4 ly
Kepler-257 c
Neptune-like · K-type orange
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Kepler-951 b
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Kepler-1737 b
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TOI-1410 c
Neptune-like · K-type orange
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TOI-1694 b
Neptune-like · K-type orange
Radius 5.34 R⊕ · 406.7 ly