Key parameters at a glance
- A radius of 4.06 Earth radii
- A mass of 15.50 Earth masses
- Surface gravity around 0.94 g
- An orbital period of 13.197 days
- Semi-major axis 0.1030 AU
- Equilibrium temperature 642 K (369 °C)
- Distance from Earth 1,878.62 light-years
- Earth Similarity Index 0.323
- Travel time at Voyager 1 speed 33,129,452 years
- Almost certainly tidally locked to its host star given the close orbit
1 sibling around Kepler-258
Kepler-258 b 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-258 b this | Neptune-like | 4.06 | 15.50 | 13.197 | 642 | 2014 |
| Kepler-258 c | Sub-Neptune | 3.61 | 12.70 | 33.653 | 470 | 2014 |
Kepler-258 b Planet Profile
Physical Specs
Classification
Planet Type
Neptune-like
Discovery
Size rank in cohort
Rank by radius
#554of 574
top 96.3%
This planet
4.06R⊕
Neptune-like median
6.39R⊕
Nearest-size peers
| Metric | Earth | Kepler-258 b | Jupiter |
|---|---|---|---|
| Radius (R⊕) | 1.00 | 4.06 | 11.21 |
| Mass (M⊕) | 1.00 | 15.50 | 317.83 |
| Density (g/cm³) | 5.51 | 1.27 | 1.33 |
| Surface Gravity (g) | 1.00 | 0.94 | 2.53 |
| Insolation (S⊕) | 1.00 | 27.79 | 0.037 |
Star Catalogue Identifiers
TIC
TIC 270854411
Gaia DR2
Gaia DR2 2128150217796747520
Gaia DR3
Gaia DR3 2128150217796747520
System
Kepler-258
Percentile among Neptune-like cohort
Orbit & Habitability
Orbital Dynamics
Year Length
A year here lasts approximately 13.20 Earth days (3.6% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.1030 AU.
Transit Fingerprint
Depth
0.214 %
Duration
3.418 h
Impact parameter b
0.110
Rp / R★
0.042638
Transit midpoint (BJD)
2,455,004.5442
Photometric dip
Transit produces a flux drop of 2,141 ppm lasting ≈ 3.42 h.
Extended Orbital Architecture
Planet / star radius ratio
0.042638
Semi-major axis / stellar radius
30.330
Impact parameter (b)
0.110
Transit mid-time (BJD)
2,455,004.5442
Angular separation (arcsec)
0.17900
Eq. Temperature
642K
(369 °C)
Insolation (S⊕)
27.79
Earth = 1.00
Earth Similarity (ESI)
0.323
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
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-258
Spectral Class
K-type orange
Effective Temperature
4,942 K — cooler than the Sun (5,778 K)
Estimated Age
13.70 Gyr — older than the Sun (4.6 Gyr)
Stellar Radius
0.915 R☉
Stellar Mass
0.820 M☉
Metallicity [Fe/H]
0.30
Extended Stellar Properties
Surface gravity (log g)
4.441 dex
Stellar density
3.030 g/cm³
Metallicity ratio
[M/H]
Multi-band Host Photometry — 16 bands
Astrometric Data
Parallax
1.708 mas
Total Proper Motion
31.941 mas/yr
PM Right Ascension
-11.47 mas/yr
PM Declination
-29.81 mas/yr
Galactic Cartesian (pc)
x = 0.280 · y = -0.628 · z = 0.726
Equatorial (J2000)
RA 294.06841° · Dec 46.57914°
Galactic ℓ, b
79.305° · 12.256°
Ecliptic λ, β
314.333° · 66.353°
HTM-20 index
-1309965895
Similar Worlds
HD 190007 b
Neptune-like · K-type orange
Radius 4.06 R⊕ · 41.5 ly
TOI-1472 b
Neptune-like · K-type orange
Radius 4.06 R⊕ · 397.4 ly
Kepler-248 c
Neptune-like · K-type orange
Radius 4.07 R⊕ · 2,409.6 ly
BD-11 4672 c
Neptune-like · K-type orange
Radius 4.04 R⊕ · 88.6 ly
Kepler-247 c
Neptune-like · K-type orange
Radius 4.09 R⊕ · 2,164.7 ly
Kepler-815 b
Neptune-like · K-type orange
Radius 4.11 R⊕ · 4,107.2 ly