Key parameters at a glance
- A radius of 2.50 Earth radii
- A mass of 6.80 Earth masses
- Surface gravity around 1.09 g
- An orbital period of 18.746 days
- Semi-major axis 0.1390 AU
- Equilibrium temperature 686 K (413 °C)
- Distance from Earth 4,531.87 light-years
- Earth Similarity Index 0.369
- Travel time at Voyager 1 speed 79,919,565 years
2 siblings around Kepler-254
Kepler-254 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-254 b | Sub-Neptune | 3.87 | 14.30 | 5.827 | 1,013 | 2014 |
| Kepler-254 c | Sub-Neptune | 2.15 | 3.20 | 12.412 | 787 | 2014 |
| Kepler-254 d this | Sub-Neptune | 2.50 | 6.80 | 18.746 | 686 | 2014 |
Kepler-254 d Planet Profile
Physical Specs
Classification
Planet Type
Sub-Neptune
Discovery
Size rank in cohort
Rank by radius
#1168of 1978
top 59.0%
This planet
2.50R⊕
Sub-Neptune median
2.71R⊕
Nearest-size peers
| Metric | Earth | Kepler-254 d | Jupiter |
|---|---|---|---|
| Radius (R⊕) | 1.00 | 2.50 | 11.21 |
| Mass (M⊕) | 1.00 | 6.80 | 317.83 |
| Density (g/cm³) | 5.51 | 2.39 | 1.33 |
| Surface Gravity (g) | 1.00 | 1.09 | 2.53 |
| Insolation (S⊕) | 1.00 | 38.84 | 0.037 |
Star Catalogue Identifiers
TIC
TIC 158665380
Gaia DR2
Gaia DR2 2130250731680096384
Gaia DR3
Gaia DR3 2130250731680096384
System
Kepler-254
Percentile among Sub-Neptune cohort
Orbit & Habitability
Orbital Dynamics
Year Length
A year here lasts approximately 18.75 Earth days (5.1% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.1390 AU.
Transit Fingerprint
Depth
0.080 %
Duration
3.961 h
Impact parameter b
0.150
Rp / R★
0.026945
Transit midpoint (BJD)
2,454,980.1291
Photometric dip
Transit produces a flux drop of 797 ppm lasting ≈ 3.96 h.
Extended Orbital Architecture
Planet / star radius ratio
0.026945
Semi-major axis / stellar radius
20.100
Impact parameter (b)
0.150
Transit mid-time (BJD)
2,454,980.1291
Angular separation (arcsec)
0.10000
Eq. Temperature
686K
(413 °C)
Insolation (S⊕)
38.84
Earth = 1.00
Earth Similarity (ESI)
0.369
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
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-254
Spectral Class
G-type yellow (Sun-like)
Effective Temperature
5,957 K — hotter than the Sun (5,778 K)
Estimated Age
0.30 Gyr — younger than the Sun (4.6 Gyr)
Stellar Radius
0.910 R☉
Stellar Mass
0.849 M☉
Metallicity [Fe/H]
-0.13
Extended Stellar Properties
Surface gravity (log g)
4.524 dex
Stellar density
1.250 g/cm³
Metallicity ratio
[Fe/H]
Multi-band Host Photometry — 16 bands
Astrometric Data
Parallax
0.691 mas
Total Proper Motion
17.527 mas/yr
PM Right Ascension
-4.79 mas/yr
PM Declination
-16.86 mas/yr
Galactic Cartesian (pc)
x = 0.217 · y = -0.662 · z = 0.717
Equatorial (J2000)
RA 288.16465° · Dec 45.81643°
Galactic ℓ, b
76.822° · 15.643°
Ecliptic λ, β
303.979° · 67.125°
HTM-20 index
1960743190
Similar Worlds
K2-231 b
Sub-Neptune · G-type yellow (Sun-like)
Radius 2.50 R⊕ · 1,047.7 ly
Kepler-106 c
Sub-Neptune · G-type yellow (Sun-like)
Radius 2.50 R⊕ · 1,449.2 ly
K2-282 b
Sub-Neptune · G-type yellow (Sun-like)
Radius 2.50 R⊕ · 1,618.7 ly
K2-6 b
Sub-Neptune · G-type yellow (Sun-like)
Radius 2.50 R⊕ · 1,033.3 ly
Kepler-672 b
Sub-Neptune · G-type yellow (Sun-like)
Radius 2.50 R⊕ · 3,372.2 ly
Kepler-738 b
Sub-Neptune · G-type yellow (Sun-like)
Radius 2.50 R⊕ · 3,632.2 ly