Key parameters at a glance
- A radius of 3.89 Earth radii
- A mass of 14.40 Earth masses
- Surface gravity around 0.95 g
- An orbital period of 4.221 days
- Semi-major axis 0.0418 AU
- Equilibrium temperature 595 K (322 °C)
- Distance from Earth 1,879.25 light-years
- Earth Similarity Index 0.353
- Travel time at Voyager 1 speed 33,140,553 years
- Almost certainly tidally locked to its host star given the close orbit
Kepler-1729 b Planet Profile
Physical Specs
Classification
Planet Type
Sub-Neptune
Discovery
Size rank in cohort
Rank by radius
#27of 1978
top 1.3%
This planet
3.89R⊕
Sub-Neptune median
2.71R⊕
Nearest-size peers
| Metric | Earth | Kepler-1729 b | Jupiter |
|---|---|---|---|
| Radius (R⊕) | 1.00 | 3.89 | 11.21 |
| Mass (M⊕) | 1.00 | 14.40 | 317.83 |
| Density (g/cm³) | 5.51 | 1.34 | 1.33 |
| Surface Gravity (g) | 1.00 | 0.95 | 2.53 |
| Insolation (S⊕) | 1.00 | 29.68 | 0.037 |
Star Catalogue Identifiers
TIC
TIC 272708868
Gaia DR2
Gaia DR2 2077201219791653248
Gaia DR3
Gaia DR3 2077201219791653248
System
Kepler-1729
Percentile among Sub-Neptune cohort
Orbit & Habitability
Orbital Dynamics
Year Length
A year here lasts approximately 4.22 Earth days (1.2% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.0418 AU.
Transit Fingerprint
Depth
0.226 %
Duration
3.098 h
Impact parameter b
0.713
Rp / R★
0.045400
Transit midpoint (BJD)
2,455,003.6223
Photometric dip
Transit produces a flux drop of 2,260 ppm lasting ≈ 3.10 h.
Extended Orbital Architecture
Planet / star radius ratio
0.045400
Semi-major axis / stellar radius
8.130
Impact parameter (b)
0.713
Transit mid-time (BJD)
2,455,003.6223
Angular separation (arcsec)
0.07250
Eq. Temperature
595K
(322 °C)
Insolation (S⊕)
29.68
Earth = 1.00
Earth Similarity (ESI)
0.353
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
Valizadegan et al. 2022Instrument
Kepler CCD Array
Publication
2022-02
Observation locale
Space
Discovery cohort
Planets confirmed in 2021 at Kepler (12 shown).
Host System: Kepler-1729
Spectral Class
K-type orange
Effective Temperature
3,837 K — cooler than the Sun (5,778 K)
Estimated Age
1.20 Gyr — younger than the Sun (4.6 Gyr)
Stellar Radius
0.517 R☉
Stellar Mass
0.544 M☉
Metallicity [Fe/H]
-0.06
Extended Stellar Properties
Surface gravity (log g)
4.747 dex
Stellar density
0.570 g/cm³
Metallicity ratio
[Fe/H]
Multi-band Host Photometry — 16 bands
Astrometric Data
Parallax
1.708 mas
Total Proper Motion
5.757 mas/yr
PM Right Ascension
-3.99 mas/yr
PM Declination
4.15 mas/yr
Galactic Cartesian (pc)
x = 0.331 · y = -0.657 · z = 0.677
Equatorial (J2000)
RA 296.69394° · Dec 42.62611°
Galactic ℓ, b
76.640° · 8.755°
Ecliptic λ, β
314.719° · 61.984°
HTM-20 index
1586275362
Similar Worlds
TOI-942 b
Sub-Neptune · K-type orange
Radius 3.89 R⊕ · 497.7 ly
HIP 4845 b
Sub-Neptune · K-type orange
Radius 3.89 R⊕ · 68.8 ly
Kepler-1024 b
Sub-Neptune · K-type orange
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Kepler-1661 b
Sub-Neptune · K-type orange
Radius 3.87 R⊕ · 1,339.2 ly
Kepler-229 d
Sub-Neptune · K-type orange
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Kepler-247 d
Sub-Neptune · K-type orange
Radius 3.94 R⊕ · 2,164.7 ly