Key parameters at a glance
- A radius of 2.05 Earth radii
- A mass of 4.86 Earth masses
- Surface gravity around 1.16 g
- An orbital period of 232.040 days
- Semi-major axis 0.7326 AU
- Equilibrium temperature 327 K (54 °C)
- Distance from Earth 2,539.63 light-years
- Earth Similarity Index 0.755
- Travel time at Voyager 1 speed 44,786,315 years
2 siblings around Kepler-311
Kepler-311 d 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-311 b | Super-Earth | 1.70 | 3.53 | 9.176 | 960 | 2014 |
| Kepler-311 c | Super-Earth | 1.43 | 2.63 | 19.738 | 744 | 2014 |
| Kepler-311 d this | Sub-Neptune | 2.05 | 4.86 | 232.040 | 327 | 2023 |
Kepler-311 d Planet Profile
Physical Specs
Classification
Planet Type
Sub-Neptune
Discovery
Size rank in cohort
Rank by radius
#1888of 1978
top 95.4%
This planet
2.05R⊕
Sub-Neptune median
2.71R⊕
Nearest-size peers
| Metric | Earth | Kepler-311 d | Jupiter |
|---|---|---|---|
| Radius (R⊕) | 1.00 | 2.05 | 11.21 |
| Mass (M⊕) | 1.00 | 4.86 | 317.83 |
| Density (g/cm³) | 5.51 | 3.10 | 1.33 |
| Surface Gravity (g) | 1.00 | 1.16 | 2.53 |
| Insolation (S⊕) | 1.00 | 2.71 | 0.037 |
Star Catalogue Identifiers
TIC
TIC 351898154
Gaia DR2
Gaia DR2 2119534646538533888
Gaia DR3
Gaia DR3 2119534646538533888
System
Kepler-311
Percentile among Sub-Neptune cohort
Orbit & Habitability
Orbital Dynamics
Year Length
A year here lasts approximately 232.04 Earth days (63.5% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.7326 AU.
Transit Fingerprint
Depth
0.029 %
Duration
12.235 h
Impact parameter b
0.610
Rp / R★
0.016278
Transit midpoint (BJD)
2,455,095.2531
Photometric dip
Transit produces a flux drop of 291 ppm lasting ≈ 12.24 h.
Extended Orbital Architecture
Planet / star radius ratio
0.016278
Semi-major axis / stellar radius
117.800
Impact parameter (b)
0.610
Transit mid-time (BJD)
2,455,095.2531
Angular separation (arcsec)
0.94100
Eq. Temperature
327K
(54 °C)
Insolation (S⊕)
2.71
Earth = 1.00
Earth Similarity (ESI)
0.755
0 = alien, 1 = Earth-identical
Inside the inner HZ boundary (too hot for liquid water) — liquid water is physically possible with adequate atmospheric pressure.
Discovery Paper
Primary reference
Valizadegan et al. 2023Instrument
Kepler CCD Array
Publication
2023-05
Observation locale
Space
Discovery cohort
Planets confirmed in 2023 at Kepler (12 shown).
Host System: Kepler-311
Spectral Class
G-type yellow (Sun-like)
Effective Temperature
5,903 K — hotter than the Sun (5,778 K)
Estimated Age
1.95 Gyr — younger than the Sun (4.6 Gyr)
Stellar Radius
1.156 R☉
Stellar Mass
0.974 M☉
Metallicity [Fe/H]
-0.10
Extended Stellar Properties
Surface gravity (log g)
4.300 dex
Stellar density
0.574 g/cm³
Metallicity ratio
[Fe/H]
Multi-band Host Photometry — 16 bands
Astrometric Data
Parallax
1.255 mas
Total Proper Motion
7.907 mas/yr
PM Right Ascension
-6.86 mas/yr
PM Declination
3.94 mas/yr
Galactic Cartesian (pc)
x = 0.142 · y = -0.666 · z = 0.732
Equatorial (J2000)
RA 282.06127° · Dec 47.08550°
Galactic ℓ, b
76.493° · 20.023°
Ecliptic λ, β
293.993° · 69.522°
HTM-20 index
1727815755
Similar Worlds
Kepler-337 c
Sub-Neptune · G-type yellow (Sun-like)
Radius 2.05 R⊕ · 2,211.3 ly
Kepler-244 c
Sub-Neptune · G-type yellow (Sun-like)
Radius 2.05 R⊕ · 3,380.6 ly
HD 110113 b
Sub-Neptune · G-type yellow (Sun-like)
Radius 2.05 R⊕ · 346.7 ly
Kepler-363 d
Sub-Neptune · G-type yellow (Sun-like)
Radius 2.05 R⊕ · 2,487.3 ly
Kepler-868 b
Sub-Neptune · G-type yellow (Sun-like)
Radius 2.05 R⊕ · 5,196.1 ly
Kepler-1958 b
Sub-Neptune · G-type yellow (Sun-like)
Radius 2.05 R⊕ · 4,306.5 ly