Key parameters at a glance
- A radius of 4.92 Earth radii
- A mass of 21.50 Earth masses
- Surface gravity around 0.89 g
- An orbital period of 16.069 days
- Semi-major axis 0.1170 AU
- Equilibrium temperature 600 K (327 °C)
- Distance from Earth 2,694.91 light-years
- Earth Similarity Index 0.316
- Travel time at Voyager 1 speed 47,524,786 years
- Almost certainly tidally locked to its host star given the close orbit
2 siblings around Kepler-229
Kepler-229 c shares its host star with 2 other confirmed planets. Side-by-side measurements below.
| Planet | Type | Radius (R⊕) | Mass (M⊕) | Period (d) | Eq. T (K) | Year |
|---|---|---|---|---|---|---|
| Kepler-229 b | Sub-Neptune | 2.20 | 5.48 | 6.253 | 823 | 2014 |
| Kepler-229 c this | Neptune-like | 4.92 | 21.50 | 16.069 | 600 | 2014 |
| Kepler-229 d | Sub-Neptune | 3.85 | 14.20 | 41.195 | 439 | 2014 |
Kepler-229 c Planet Profile
Physical Specs
Classification
Planet Type
Neptune-like
Discovery
Size rank in cohort
Rank by radius
#393of 574
top 68.3%
This planet
4.92R⊕
Neptune-like median
6.39R⊕
Nearest-size peers
| Metric | Earth | Kepler-229 c | Jupiter |
|---|---|---|---|
| Radius (R⊕) | 1.00 | 4.92 | 11.21 |
| Mass (M⊕) | 1.00 | 21.50 | 317.83 |
| Density (g/cm³) | 5.51 | 0.99 | 1.33 |
| Surface Gravity (g) | 1.00 | 0.89 | 2.53 |
| Insolation (S⊕) | 1.00 | 21.64 | 0.037 |
Star Catalogue Identifiers
TIC
TIC 399912169
Gaia DR2
Gaia DR2 2131114947819394816
Gaia DR3
Gaia DR3 2131114947819394816
System
Kepler-229
Percentile among Neptune-like cohort
Orbit & Habitability
Orbital Dynamics
Year Length
A year here lasts approximately 16.07 Earth days (4.4% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.1170 AU.
Transit Fingerprint
Depth
0.491 %
Duration
3.546 h
Impact parameter b
0.000
Rp / R★
0.065087
Transit midpoint (BJD)
2,455,006.6217
Photometric dip
Transit produces a flux drop of 4,914 ppm lasting ≈ 3.55 h.
Extended Orbital Architecture
Planet / star radius ratio
0.065087
Semi-major axis / stellar radius
36.850
Impact parameter (b)
0.000
Transit mid-time (BJD)
2,455,006.6217
Angular separation (arcsec)
0.14200
Eq. Temperature
600K
(327 °C)
Insolation (S⊕)
21.64
Earth = 1.00
Earth Similarity (ESI)
0.316
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
Rowe et al. 2014Instrument
Kepler CCD Array
Publication
2014-03
Observation locale
Space
Discovery cohort
Planets confirmed in 2014 at Kepler (12 shown).
Host System: Kepler-229
Spectral Class
K-type orange
Effective Temperature
5,120 K — cooler than the Sun (5,778 K)
Estimated Age
2.04 Gyr — younger than the Sun (4.6 Gyr)
Stellar Radius
0.728 R☉
Stellar Mass
0.808 M☉
Metallicity [Fe/H]
0.06
Extended Stellar Properties
Surface gravity (log g)
4.633 dex
Stellar density
1.940 g/cm³
Metallicity ratio
[Fe/H]
Multi-band Host Photometry — 16 bands
Astrometric Data
Parallax
1.182 mas
Total Proper Motion
5.627 mas/yr
PM Right Ascension
-1.33 mas/yr
PM Declination
-5.47 mas/yr
Galactic Cartesian (pc)
x = 0.194 · y = -0.635 · z = 0.748
Equatorial (J2000)
RA 286.99948° · Dec 48.37579°
Galactic ℓ, b
78.978° · 17.348°
Ecliptic λ, β
304.224° · 69.803°
HTM-20 index
-565252898
Similar Worlds
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Neptune-like · K-type orange
Radius 4.92 R⊕ · 2,508.6 ly
TOI-544 c
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HIP 19976 b
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Kepler-257 d
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TOI-1272 c
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TOI-880 c
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Radius 4.95 R⊕ · 197.9 ly