Key parameters at a glance
- A radius of 1.22 Earth radii
- A mass of 1.98 Earth masses
- Surface gravity around 1.33 g
- An orbital period of 8.109 days
- Semi-major axis 0.0760 AU
- Equilibrium temperature 800 K (527 °C)
- Distance from Earth 3,196.78 light-years
- Earth Similarity Index 0.392
- Travel time at Voyager 1 speed 56,375,193 years
2 siblings around Kepler-226
Kepler-226 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-226 b | Super-Earth | 1.55 | 24.00 | 3.941 | 1,018 | 2014 |
| Kepler-226 c | Sub-Neptune | 2.27 | 45.20 | 5.350 | 919 | 2014 |
| Kepler-226 d this | Rocky Terrestrial | 1.22 | 1.98 | 8.109 | 800 | 2014 |
Kepler-226 d Planet Profile
Physical Specs
Classification
Planet Type
Rocky Terrestrial
Discovery
Size rank in cohort
Rank by radius
#35of 570
top 6.0%
This planet
1.22R⊕
Rocky Terrestrial median
1.01R⊕
Nearest-size peers
| Metric | Earth | Kepler-226 d | Jupiter |
|---|---|---|---|
| Radius (R⊕) | 1.00 | 1.22 | 11.21 |
| Mass (M⊕) | 1.00 | 1.98 | 317.83 |
| Density (g/cm³) | 5.51 | 5.99 | 1.33 |
| Surface Gravity (g) | 1.00 | 1.33 | 2.53 |
| Insolation (S⊕) | 1.00 | 103.65 | 0.037 |
Star Catalogue Identifiers
TIC
TIC 63204017
Gaia DR2
Gaia DR2 2128504397979254528
Gaia DR3
Gaia DR3 2128504397979254528
System
Kepler-226
Percentile among Rocky Terrestrial cohort
Orbit & Habitability
Orbital Dynamics
Year Length
A year here lasts approximately 8.11 Earth days (2.2% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.0760 AU.
Transit Fingerprint
Depth
0.022 %
Duration
3.698 h
Impact parameter b
0.060
Rp / R★
0.013127
Transit midpoint (BJD)
2,454,965.8033
Photometric dip
Transit produces a flux drop of 217 ppm lasting ≈ 3.70 h.
Extended Orbital Architecture
Planet / star radius ratio
0.013127
Semi-major axis / stellar radius
17.460
Impact parameter (b)
0.060
Transit mid-time (BJD)
2,454,965.8033
Angular separation (arcsec)
0.07750
Eq. Temperature
800K
(527 °C)
Insolation (S⊕)
103.65
Earth = 1.00
Earth Similarity (ESI)
0.392
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-226
Spectral Class
G-type yellow (Sun-like)
Effective Temperature
5,571 K — cooler than the Sun (5,778 K)
Estimated Age
4.17 Gyr — younger than the Sun (4.6 Gyr)
Stellar Radius
0.802 R☉
Stellar Mass
0.904 M☉
Metallicity [Fe/H]
0.09
Extended Stellar Properties
Surface gravity (log g)
4.586 dex
Stellar density
1.430 g/cm³
Metallicity ratio
[Fe/H]
Multi-band Host Photometry — 16 bands
Astrometric Data
Parallax
0.992 mas
Total Proper Motion
10.217 mas/yr
PM Right Ascension
-6.26 mas/yr
PM Declination
-8.07 mas/yr
Galactic Cartesian (pc)
x = 0.255 · y = -0.620 · z = 0.742
Equatorial (J2000)
RA 292.37609° · Dec 47.88096°
Galactic ℓ, b
79.988° · 13.859°
Ecliptic λ, β
312.980° · 68.008°
HTM-20 index
-603487203
Similar Worlds
Kepler-1215 b
Rocky Terrestrial · G-type yellow (Sun-like)
Radius 1.22 R⊕ · 2,156.0 ly
Kepler-908 b
Rocky Terrestrial · G-type yellow (Sun-like)
Radius 1.22 R⊕ · 948.6 ly
Kepler-295 b
Rocky Terrestrial · G-type yellow (Sun-like)
Radius 1.22 R⊕ · 5,542.0 ly
K2-336 b
Rocky Terrestrial · G-type yellow (Sun-like)
Radius 1.22 R⊕ · 780.5 ly
Kepler-1311 c
Rocky Terrestrial · G-type yellow (Sun-like)
Radius 1.22 R⊕ · 2,825.6 ly
EPIC 201615463 c
Rocky Terrestrial · G-type yellow (Sun-like)
Radius 1.22 R⊕ · 1,555.4 ly