Key parameters at a glance
- A radius of 3.10 Earth radii
- A mass of 9.80 Earth masses
- Surface gravity around 1.02 g
- An orbital period of 41.750 days
- Semi-major axis 0.2310 AU
- Equilibrium temperature 486 K (213 °C)
- Distance from Earth 1,881.74 light-years
- Earth Similarity Index 0.468
- Travel time at Voyager 1 speed 33,184,554 years
1 sibling around Kepler-209
Kepler-209 c 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-209 b | Sub-Neptune | 2.26 | 5.73 | 16.088 | 668 | 2014 |
| Kepler-209 c this | Sub-Neptune | 3.10 | 9.80 | 41.750 | 486 | 2014 |
Kepler-209 c Planet Profile
Physical Specs
Classification
Planet Type
Sub-Neptune
Discovery
Size rank in cohort
Rank by radius
#433of 1978
top 21.8%
This planet
3.10R⊕
Sub-Neptune median
2.71R⊕
Nearest-size peers
| Metric | Earth | Kepler-209 c | Jupiter |
|---|---|---|---|
| Radius (R⊕) | 1.00 | 3.10 | 11.21 |
| Mass (M⊕) | 1.00 | 9.80 | 317.83 |
| Density (g/cm³) | 5.51 | 1.81 | 1.33 |
| Surface Gravity (g) | 1.00 | 1.02 | 2.53 |
| Insolation (S⊕) | 1.00 | 13.64 | 0.037 |
Star Catalogue Identifiers
TIC
TIC 159652365
Gaia DR2
Gaia DR2 2101964558106974848
Gaia DR3
Gaia DR3 2101964558106974848
System
Kepler-209
Percentile among Sub-Neptune cohort
Orbit & Habitability
Orbital Dynamics
Year Length
A year here lasts approximately 41.75 Earth days (11.4% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.2310 AU.
Transit Fingerprint
Depth
0.106 %
Duration
5.630 h
Impact parameter b
0.580
Rp / R★
0.037070
Transit midpoint (BJD)
2,454,986.8399
Photometric dip
Transit produces a flux drop of 1,055 ppm lasting ≈ 5.63 h.
Extended Orbital Architecture
Planet / star radius ratio
0.037070
Semi-major axis / stellar radius
21.430
Impact parameter (b)
0.580
Transit mid-time (BJD)
2,454,986.8399
Angular separation (arcsec)
0.40000
Eq. Temperature
486K
(213 °C)
Insolation (S⊕)
13.64
Earth = 1.00
Earth Similarity (ESI)
0.468
0 = alien, 1 = Earth-identical
Inside the inner HZ boundary (too hot for liquid water) — the surface is too hot to retain surface water.
Detection Signatures
Transit photometry
A transit dip has been observed from at least one telescope.
Transit timing variations
Gravitational interactions from neighbours have been detected.
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-209
Spectral Class
G-type yellow (Sun-like)
Effective Temperature
5,513 K — cooler than the Sun (5,778 K)
Estimated Age
1.95 Gyr — younger than the Sun (4.6 Gyr)
Stellar Radius
0.935 R☉
Stellar Mass
0.971 M☉
Metallicity [Fe/H]
0.11
Extended Stellar Properties
Surface gravity (log g)
4.472 dex
Stellar density
1.340 g/cm³
Metallicity ratio
[M/H]
Multi-band Host Photometry — 16 bands
Astrometric Data
Parallax
1.705 mas
Total Proper Motion
20.569 mas/yr
PM Right Ascension
-10.14 mas/yr
PM Declination
-17.90 mas/yr
Galactic Cartesian (pc)
x = 0.266 · y = -0.686 · z = 0.677
Equatorial (J2000)
RA 291.16946° · Dec 42.64073°
Galactic ℓ, b
74.756° · 12.372°
Ecliptic λ, β
306.427° · 63.427°
HTM-20 index
349126560
Similar Worlds
Kepler-104 b
Sub-Neptune · G-type yellow (Sun-like)
Radius 3.10 R⊕ · 1,307.2 ly
Kepler-536 b
Sub-Neptune · G-type yellow (Sun-like)
Radius 3.10 R⊕ · 1,507.9 ly
Kepler-282 e
Sub-Neptune · G-type yellow (Sun-like)
Radius 3.10 R⊕ · 4,362.7 ly
TOI-1062 c
Sub-Neptune · G-type yellow (Sun-like)
Radius 3.10 R⊕ · 268.0 ly
Kepler-692 b
Sub-Neptune · G-type yellow (Sun-like)
Radius 3.11 R⊕ · 3,233.3 ly
Kepler-227 b
Sub-Neptune · G-type yellow (Sun-like)
Radius 3.11 R⊕ · 3,532.5 ly