Key parameters at a glance
- A radius of 2.26 Earth radii
- A mass of 5.73 Earth masses
- Surface gravity around 1.12 g
- An orbital period of 10.932 days
- Semi-major axis 0.0818 AU
- Equilibrium temperature 456 K (183 °C)
- Distance from Earth 661.91 light-years
- Earth Similarity Index 0.559
- Travel time at Voyager 1 speed 11,672,796 years
- Almost certainly tidally locked to its host star given the close orbit
1 sibling around K2-5
K2-5 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 |
|---|---|---|---|---|---|---|
| K2-5 b | Super-Earth | 1.91 | 4.31 | 5.736 | 565 | 2015 |
| K2-5 c this | Sub-Neptune | 2.26 | 5.73 | 10.932 | 456 | 2015 |
K2-5 c Planet Profile
Physical Specs
Classification
Planet Type
Sub-Neptune
Discovery
Size rank in cohort
Rank by radius
#1572of 1978
top 79.4%
This planet
2.26R⊕
Sub-Neptune median
2.71R⊕
Nearest-size peers
| Metric | Earth | K2-5 c | Jupiter |
|---|---|---|---|
| Radius (R⊕) | 1.00 | 2.26 | 11.21 |
| Mass (M⊕) | 1.00 | 5.73 | 317.83 |
| Density (g/cm³) | 5.51 | 2.73 | 1.33 |
| Surface Gravity (g) | 1.00 | 1.12 | 2.53 |
| Insolation (S⊕) | 1.00 | 10.20 | 0.037 |
Star Catalogue Identifiers
TIC
TIC 38064757
Gaia DR2
Gaia DR2 3791512745687354496
Gaia DR3
Gaia DR3 3791512745687354496
System
K2-5
Percentile among Sub-Neptune cohort
Orbit & Habitability
Orbital Dynamics
Year Length
A year here lasts approximately 10.93 Earth days (3.0% of a terrestrial year) at a mean orbital distance of 0.0818 AU.
Transit Fingerprint
Depth
0.138 %
Duration
3.498 h
Impact parameter b
0.830
Rp / R★
0.036010
Transit midpoint (BJD)
2,456,814.6010
Photometric dip
Transit produces a flux drop of 1,378 ppm lasting ≈ 3.50 h.
Extended Orbital Architecture
Planet / star radius ratio
0.036010
Semi-major axis / stellar radius
15.600
Impact parameter (b)
0.830
Transit mid-time (BJD)
2,456,814.6010
Angular separation (arcsec)
0.40300
Eq. Temperature
456K
(183 °C)
Insolation (S⊕)
10.20
Earth = 1.00
Earth Similarity (ESI)
0.559
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
Montet et al. 2015Instrument
Kepler CCD Array
Publication
2015-08
Observation locale
Space
Discovery cohort
Planets confirmed in 2015 at K2 (12 shown).
Host System: K2-5
Spectral Class
K-type orange
Effective Temperature
3,930 K — cooler than the Sun (5,778 K)
Estimated Age
—
Stellar Radius
0.570 R☉
Stellar Mass
0.610 M☉
Metallicity [Fe/H]
-0.33
Extended Stellar Properties
Surface gravity (log g)
4.710 dex
Stellar density
4.405 g/cm³
Metallicity ratio
[Fe/H]
Multi-band Host Photometry — 17 bands
Astrometric Data
Parallax
4.899 mas
Total Proper Motion
35.111 mas/yr
PM Right Ascension
-11.07 mas/yr
PM Declination
33.32 mas/yr
Galactic Cartesian (pc)
x = -0.982 · y = 0.186 · z = -0.033
Equatorial (J2000)
RA 169.30346° · Dec -1.87783°
Galactic ℓ, b
261.144° · 53.173°
Ecliptic λ, β
170.904° · -5.961°
HTM-20 index
972305279
Similar Worlds
Kepler-1996 b
Sub-Neptune · K-type orange
Radius 2.26 R⊕ · 1,436.9 ly
K2-346 b
Sub-Neptune · K-type orange
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Kepler-1261 b
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Radius 2.26 R⊕ · 2,427.6 ly
Kepler-568 b
Sub-Neptune · K-type orange
Radius 2.26 R⊕ · 426.1 ly
Kepler-1242 b
Sub-Neptune · K-type orange
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Kepler-1388 c
Sub-Neptune · K-type orange
Radius 2.26 R⊕ · 1,480.1 ly