Key parameters at a glance
- A radius of 2.96 Earth radii
- A mass of 9.06 Earth masses
- Surface gravity around 1.03 g
- An orbital period of 24.340 days
- Semi-major axis 0.1648 AU
- Equilibrium temperature 737 K (464 °C)
- Distance from Earth 3,861.30 light-years
- Earth Similarity Index 0.322
- Travel time at Voyager 1 speed 68,093,945 years
1 sibling around Kepler-1129
Kepler-1129 b 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-1129 b this | Sub-Neptune | 2.96 | 9.06 | 24.340 | 737 | 2016 |
| Kepler-1129 c | Sub-Neptune | 2.73 | 7.90 | 76.537 | 503 | 2016 |
Kepler-1129 b Planet Profile
Physical Specs
Classification
Planet Type
Sub-Neptune
Discovery
Size rank in cohort
Rank by radius
#551of 1978
top 27.8%
This planet
2.96R⊕
Sub-Neptune median
2.71R⊕
Nearest-size peers
| Metric | Earth | Kepler-1129 b | Jupiter |
|---|---|---|---|
| Radius (R⊕) | 1.00 | 2.96 | 11.21 |
| Mass (M⊕) | 1.00 | 9.06 | 317.83 |
| Density (g/cm³) | 5.51 | 1.92 | 1.33 |
| Surface Gravity (g) | 1.00 | 1.03 | 2.53 |
| Insolation (S⊕) | 1.00 | 32.27 | 0.037 |
Star Catalogue Identifiers
TIC
TIC 137212833
Gaia DR2
Gaia DR2 2101651781408908160
Gaia DR3
Gaia DR3 2101651781408908160
System
Kepler-1129
Percentile among Sub-Neptune cohort
Orbit & Habitability
Orbital Dynamics
Year Length
A year here lasts approximately 24.34 Earth days (6.7% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.1648 AU.
Transit Fingerprint
Depth
0.078 %
Duration
3.292 h
Impact parameter b
0.830
Rp / R★
0.026607
Transit midpoint (BJD)
2,454,969.0594
Photometric dip
Transit produces a flux drop of 777 ppm lasting ≈ 3.29 h.
Extended Orbital Architecture
Planet / star radius ratio
0.026607
Semi-major axis / stellar radius
21.500
Impact parameter (b)
0.830
Transit mid-time (BJD)
2,454,969.0594
Angular separation (arcsec)
0.13900
Eq. Temperature
737K
(464 °C)
Insolation (S⊕)
32.27
Earth = 1.00
Earth Similarity (ESI)
0.322
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. 2016Instrument
Kepler CCD Array
Publication
2016-05
Observation locale
Space
Discovery cohort
Planets confirmed in 2016 at Kepler (12 shown).
Host System: Kepler-1129
Spectral Class
G-type yellow (Sun-like)
Effective Temperature
5,831 K — hotter than the Sun (5,778 K)
Estimated Age
4.07 Gyr — younger than the Sun (4.6 Gyr)
Stellar Radius
1.000 R☉
Stellar Mass
1.000 M☉
Metallicity [Fe/H]
-0.04
Extended Stellar Properties
Surface gravity (log g)
4.440 dex
Stellar density
1.190 g/cm³
Metallicity ratio
[Fe/H]
Multi-band Host Photometry — 16 bands
Astrometric Data
Parallax
0.817 mas
Total Proper Motion
6.686 mas/yr
PM Right Ascension
1.73 mas/yr
PM Declination
-6.46 mas/yr
Galactic Cartesian (pc)
x = 0.277 · y = -0.698 · z = 0.660
Equatorial (J2000)
RA 291.60450° · Dec 41.30933°
Galactic ℓ, b
73.676° · 11.500°
Ecliptic λ, β
306.176° · 62.062°
HTM-20 index
-514565195
Similar Worlds
Kepler-650 b
Sub-Neptune · G-type yellow (Sun-like)
Radius 2.96 R⊕ · 2,884.5 ly
TOI-1751 b
Sub-Neptune · G-type yellow (Sun-like)
Radius 2.95 R⊕ · 369.6 ly
Kepler-344 c
Sub-Neptune · G-type yellow (Sun-like)
Radius 2.95 R⊕ · 3,271.1 ly
HD 134606 b
Sub-Neptune · G-type yellow (Sun-like)
Radius 2.97 R⊕ · 87.4 ly
Kepler-154 c
Sub-Neptune · G-type yellow (Sun-like)
Radius 2.95 R⊕ · 2,985.0 ly
Kepler-949 c
Sub-Neptune · G-type yellow (Sun-like)
Radius 2.97 R⊕ · 1,585.5 ly