Key parameters at a glance
- A radius of 2.71 Earth radii
- A mass of 7.81 Earth masses
- Surface gravity around 1.06 g
- An orbital period of 4.014 days
- Semi-major axis 0.0461 AU
- Equilibrium temperature 1,003 K (730 °C)
- Distance from Earth 1,352.60 light-years
- Earth Similarity Index 0.242
- Travel time at Voyager 1 speed 23,853,012 years
- Almost certainly tidally locked to its host star given the close orbit
K2-250 b Planet Profile
Physical Specs
Classification
Planet Type
Sub-Neptune
Discovery
Size rank in cohort
Rank by radius
#846of 1978
top 42.7%
This planet
2.71R⊕
Sub-Neptune median
2.71R⊕
Nearest-size peers
| Metric | Earth | K2-250 b | Jupiter |
|---|---|---|---|
| Radius (R⊕) | 1.00 | 2.71 | 11.21 |
| Mass (M⊕) | 1.00 | 7.81 | 317.83 |
| Density (g/cm³) | 5.51 | 2.15 | 1.33 |
| Surface Gravity (g) | 1.00 | 1.06 | 2.53 |
| Insolation (S⊕) | 1.00 | — | 0.037 |
Star Catalogue Identifiers
TIC
TIC 98591691
Gaia DR2
Gaia DR2 3582706794559052160
Gaia DR3
Gaia DR3 3582706794559052160
System
K2-250
Percentile among Sub-Neptune cohort
Orbit & Habitability
Orbital Dynamics
Year Length
A year here lasts approximately 4.01 Earth days (1.1% of a terrestrial year) on a mildly elliptical path at a mean orbital distance of 0.0461 AU.
Transit Fingerprint
Depth
0.097 %
Duration
2.366 h
Impact parameter b
0.350
Rp / R★
0.031100
Transit midpoint (BJD)
2,457,620.2535
Photometric dip
Transit produces a flux drop of 970 ppm lasting ≈ 2.37 h.
Extended Orbital Architecture
Planet / star radius ratio
0.031100
Semi-major axis / stellar radius
12.440
Impact parameter (b)
0.350
Transit mid-time (BJD)
2,457,620.2535
Long. of periastron (ω)
-40.00°
Angular separation (arcsec)
0.11100
Eq. Temperature
1,003K
(730 °C)
Insolation (S⊕)
—
Earth = 1.00
Earth Similarity (ESI)
0.242
0 = alien, 1 = Earth-identical
Insufficient insolation data — the dayside is scorched. Close-orbiting tidally-locked around a cool host.
Discovery Paper
Primary reference
Livingston et al. 2018Instrument
Kepler CCD Array
Publication
2018-08
Observation locale
Space
Discovery cohort
Planets confirmed in 2018 at K2 (12 shown).
Host System: K2-250
Spectral Class
K-type orange
Effective Temperature
5,003 K — cooler than the Sun (5,778 K)
Estimated Age
8.20 Gyr — older than the Sun (4.6 Gyr)
Stellar Radius
0.797 R☉
Stellar Mass
0.809 M☉
Metallicity [Fe/H]
-0.02
Extended Stellar Properties
Surface gravity (log g)
4.544 dex
Stellar density
2.260 g/cm³
Rotational v·sin i
2.20 km/s
Metallicity ratio
[Fe/H]
Multi-band Host Photometry — 12 bands
Astrometric Data
Parallax
2.383 mas
Total Proper Motion
51.257 mas/yr
PM Right Ascension
-50.30 mas/yr
PM Declination
9.84 mas/yr
Galactic Cartesian (pc)
x = -0.984 · y = -0.087 · z = -0.156
Equatorial (J2000)
RA 185.03154° · Dec -8.97574°
Galactic ℓ, b
289.982° · 53.107°
Ecliptic λ, β
188.182° · -6.239°
HTM-20 index
-847984233
Similar Worlds
K2-182 b
Sub-Neptune · K-type orange
Radius 2.71 R⊕ · 505.0 ly
Kepler-48 c
Sub-Neptune · K-type orange
Radius 2.71 R⊕ · 1,000.4 ly
Kepler-1058 b
Sub-Neptune · K-type orange
Radius 2.72 R⊕ · 1,604.7 ly
TOI-712 c
Sub-Neptune · K-type orange
Radius 2.70 R⊕ · 191.2 ly
Kepler-1539 b
Sub-Neptune · K-type orange
Radius 2.70 R⊕ · 2,440.7 ly
Kepler-290 c
Sub-Neptune · K-type orange
Radius 2.70 R⊕ · 2,265.6 ly