Key parameters at a glance
- A radius of 4.00 Earth radii
- A mass of 15.10 Earth masses
- Surface gravity around 0.94 g
- An orbital period of 29.666 days
- Semi-major axis 0.1829 AU
- Equilibrium temperature 644 K (371 °C)
- Distance from Earth 3,548.15 light-years
- Earth Similarity Index 0.324
- Travel time at Voyager 1 speed 62,571,680 years
1 sibling around Kepler-647
Kepler-647 c shares its host star with 1 other confirmed planet. Side-by-side measurements below.
| Planet | Type | Radius (R⊕) | Mass (M⊕) | Period (d) | Eq. T (K) | Year |
|---|---|---|---|---|---|---|
| Kepler-647 b | Rocky Terrestrial | 1.17 | 1.71 | 16.225 | 788 | 2016 |
| Kepler-647 c this | Neptune-like | 4.00 | 15.10 | 29.666 | 644 | 2020 |
Kepler-647 c Planet Profile
Physical Specs
Classification
Planet Type
Neptune-like
Discovery
Size rank in cohort
Rank by radius
#570of 574
top 99.1%
This planet
4.00R⊕
Neptune-like median
6.39R⊕
Nearest-size peers
| Metric | Earth | Kepler-647 c | Jupiter |
|---|---|---|---|
| Radius (R⊕) | 1.00 | 4.00 | 11.21 |
| Mass (M⊕) | 1.00 | 15.10 | 317.83 |
| Density (g/cm³) | 5.51 | 1.30 | 1.33 |
| Surface Gravity (g) | 1.00 | 0.94 | 2.53 |
| Insolation (S⊕) | 1.00 | 69.00 | 0.037 |
Star Catalogue Identifiers
TIC
TIC 164786172
Gaia DR2
Gaia DR2 2106710978002603904
Gaia DR3
Gaia DR3 2106710978002603904
System
Kepler-647
Percentile among Neptune-like cohort
Orbit & Habitability
Orbital Dynamics
Year Length
A year here lasts approximately 29.67 Earth days (8.1% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.1829 AU.
Transit Fingerprint
Depth
0.067 %
Duration
8.412 h
Impact parameter b
0.724
Rp / R★
0.025400
Transit midpoint (BJD)
2,455,022.3702
Photometric dip
Transit produces a flux drop of 668 ppm lasting ≈ 8.41 h.
Extended Orbital Architecture
Planet / star radius ratio
0.025400
Semi-major axis / stellar radius
27.582
Impact parameter (b)
0.724
Transit mid-time (BJD)
2,455,022.3702
Angular separation (arcsec)
0.16800
Eq. Temperature
644K
(371 °C)
Insolation (S⊕)
69.00
Earth = 1.00
Earth Similarity (ESI)
0.324
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
Armstrong et al. 2021Instrument
Kepler CCD Array
Publication
2021-07
Observation locale
Space
Discovery cohort
Planets confirmed in 2020 at Kepler (12 shown).
Host System: Kepler-647
Spectral Class
G-type yellow (Sun-like)
Effective Temperature
5,907 K — hotter than the Sun (5,778 K)
Estimated Age
2.75 Gyr — younger than the Sun (4.6 Gyr)
Stellar Radius
1.546 R☉
Stellar Mass
1.070 M☉
Metallicity [Fe/H]
-0.41
Extended Stellar Properties
Surface gravity (log g)
4.089 dex
Stellar density
0.408 g/cm³
Metallicity ratio
[M/H]
Multi-band Host Photometry — 16 bands
Astrometric Data
Parallax
0.890 mas
Total Proper Motion
11.957 mas/yr
PM Right Ascension
0.83 mas/yr
PM Declination
-11.93 mas/yr
Galactic Cartesian (pc)
x = 0.182 · y = -0.689 · z = 0.702
Equatorial (J2000)
RA 284.78830° · Dec 44.59162°
Galactic ℓ, b
74.705° · 17.385°
Ecliptic λ, β
297.277° · 66.636°
HTM-20 index
1004515801
Similar Worlds
Kepler-4 b
Neptune-like · G-type yellow (Sun-like)
Radius 4.00 R⊕ · 1,591.4 ly
HD 177565 b
Neptune-like · G-type yellow (Sun-like)
Radius 4.00 R⊕ · 55.2 ly
Kepler-27 b
Neptune-like · G-type yellow (Sun-like)
Radius 4.00 R⊕ · 3,406.2 ly
Kepler-33 e
Neptune-like · G-type yellow (Sun-like)
Radius 4.02 R⊕ · 3,943.7 ly
K2-360 c
Neptune-like · G-type yellow (Sun-like)
Radius 4.02 R⊕ · 757.0 ly
K2-7 b
Neptune-like · G-type yellow (Sun-like)
Radius 4.04 R⊕ · 2,408.8 ly