Key parameters at a glance
- A radius of 3.52 Earth radii
- A mass of 12.20 Earth masses
- Surface gravity around 0.98 g
- An orbital period of 20.506 days
- Semi-major axis 0.1326 AU
- Equilibrium temperature 518 K (245 °C)
- Distance from Earth 2,066.72 light-years
- Earth Similarity Index 0.419
- Travel time at Voyager 1 speed 36,446,607 years
- Almost certainly tidally locked to its host star given the close orbit
Kepler-687 b Planet Profile
Physical Specs
Classification
Planet Type
Sub-Neptune
Discovery
Size rank in cohort
Rank by radius
#169of 1978
top 8.5%
This planet
3.52R⊕
Sub-Neptune median
2.71R⊕
Nearest-size peers
| Metric | Earth | Kepler-687 b | Jupiter |
|---|---|---|---|
| Radius (R⊕) | 1.00 | 3.52 | 11.21 |
| Mass (M⊕) | 1.00 | 12.20 | 317.83 |
| Density (g/cm³) | 5.51 | 1.54 | 1.33 |
| Surface Gravity (g) | 1.00 | 0.98 | 2.53 |
| Insolation (S⊕) | 1.00 | 15.65 | 0.037 |
Star Catalogue Identifiers
TIC
TIC 121988890
Gaia DR2
Gaia DR2 2101000836165429504
Gaia DR3
Gaia DR3 2101000836165429504
System
Kepler-687
Percentile among Sub-Neptune cohort
Orbit & Habitability
Orbital Dynamics
Year Length
A year here lasts approximately 20.51 Earth days (5.6% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.1326 AU.
Transit Fingerprint
Depth
0.211 %
Duration
4.060 h
Impact parameter b
0.790
Rp / R★
0.043572
Transit midpoint (BJD)
2,455,014.4347
Photometric dip
Transit produces a flux drop of 2,106 ppm lasting ≈ 4.06 h.
Extended Orbital Architecture
Planet / star radius ratio
0.043572
Semi-major axis / stellar radius
39.050
Impact parameter (b)
0.790
Transit mid-time (BJD)
2,455,014.4347
Angular separation (arcsec)
0.20900
Eq. Temperature
518K
(245 °C)
Insolation (S⊕)
15.65
Earth = 1.00
Earth Similarity (ESI)
0.419
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.
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-687
Spectral Class
K-type orange
Effective Temperature
4,841 K — cooler than the Sun (5,778 K)
Estimated Age
5.50 Gyr — older than the Sun (4.6 Gyr)
Stellar Radius
0.730 R☉
Stellar Mass
0.770 M☉
Metallicity [Fe/H]
-0.04
Extended Stellar Properties
Surface gravity (log g)
4.600 dex
Stellar density
2.650 g/cm³
Metallicity ratio
[Fe/H]
Multi-band Host Photometry — 16 bands
Astrometric Data
Parallax
1.550 mas
Total Proper Motion
5.357 mas/yr
PM Right Ascension
2.80 mas/yr
PM Declination
4.57 mas/yr
Galactic Cartesian (pc)
x = 0.256 · y = -0.732 · z = 0.631
Equatorial (J2000)
RA 289.31546° · Dec 39.15329°
Galactic ℓ, b
70.917° · 12.140°
Ecliptic λ, β
301.393° · 60.504°
HTM-20 index
-168352698
Similar Worlds
K2-283 b
Sub-Neptune · K-type orange
Radius 3.52 R⊕ · 1,314.1 ly
TOI-1246 e
Sub-Neptune · K-type orange
Radius 3.51 R⊕ · 552.6 ly
K2-285 c
Sub-Neptune · K-type orange
Radius 3.53 R⊕ · 505.4 ly
TOI-2076 c
Sub-Neptune · K-type orange
Radius 3.54 R⊕ · 136.7 ly
TOI-5076 b
Sub-Neptune · K-type orange
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KOBE-1 c
Sub-Neptune · K-type orange
Radius 3.56 R⊕ · 78.2 ly