Key parameters at a glance
- A radius of 2.00 Earth radii
- A mass of 4.66 Earth masses
- Surface gravity around 1.17 g
- An orbital period of 16.035 days
- Distance from Earth 475.21 light-years
- Earth Similarity Index 0.785
- Travel time at Voyager 1 speed 8,380,373 years
- Almost certainly tidally locked to its host star given the close orbit
2 siblings around K2-381
K2-381 c shares its host star with 2 other confirmed planets. Side-by-side measurements below.
K2-381 c Planet Profile
Physical Specs
Classification
Planet Type
Sub-Neptune
Discovery
Size rank in cohort
Rank by radius
#1955of 1978
top 98.8%
This planet
2.00R⊕
Sub-Neptune median
2.71R⊕
Nearest-size peers
| Metric | Earth | K2-381 c | Jupiter |
|---|---|---|---|
| Radius (R⊕) | 1.00 | 2.00 | 11.21 |
| Mass (M⊕) | 1.00 | 4.66 | 317.83 |
| Density (g/cm³) | 5.51 | 3.20 | 1.33 |
| Surface Gravity (g) | 1.00 | 1.17 | 2.53 |
| Insolation (S⊕) | 1.00 | — | 0.037 |
Star Catalogue Identifiers
TIC
TIC 10195089
Gaia DR2
Gaia DR2 4081376064109034496
Gaia DR3
Gaia DR3 4081376064109034496
System
K2-381
Percentile among Sub-Neptune cohort
Orbit & Habitability
Orbital Dynamics
Year Length
A year here lasts approximately 16.03 Earth days (4.4% of a terrestrial year).
Transit Fingerprint
Depth
0.095 %
Duration
3.070 h
Impact parameter b
0.338
Rp / R★
0.027100
Transit midpoint (BJD)
2,457,304.2916
Photometric dip
Transit produces a flux drop of 947 ppm lasting ≈ 3.07 h.
Extended Orbital Architecture
Planet / star radius ratio
0.027100
Semi-major axis / stellar radius
39.390
Impact parameter (b)
0.338
Transit mid-time (BJD)
2,457,304.2916
Eq. Temperature
—
Insolation (S⊕)
—
Earth = 1.00
Earth Similarity (ESI)
0.785
0 = alien, 1 = Earth-identical
Insufficient insolation data. Close-orbiting tidally-locked around a cool host.
Discovery Paper
Primary reference
Christiansen et al. 2022Instrument
Kepler CCD Array
Publication
2022-03
Observation locale
Space
Discovery cohort
Planets confirmed in 2022 at K2 (12 shown).
Host System: K2-381
Spectral Class
K-type orange
Effective Temperature
4,473 K — cooler than the Sun (5,778 K)
Estimated Age
—
Stellar Radius
0.675 R☉
Stellar Mass
0.754 M☉
Metallicity [Fe/H]
-0.24
Extended Stellar Properties
Surface gravity (log g)
4.653 dex
Stellar density
3.243 g/cm³
Metallicity ratio
[Fe/H]
Multi-band Host Photometry — 12 bands
Astrometric Data
Parallax
6.835 mas
Total Proper Motion
37.644 mas/yr
PM Right Ascension
-34.80 mas/yr
PM Declination
14.35 mas/yr
Galactic Cartesian (pc)
x = 0.289 · y = -0.888 · z = -0.358
Equatorial (J2000)
RA 288.02676° · Dec -21.00758°
Galactic ℓ, b
16.131° · -13.786°
Ecliptic λ, β
286.793° · 1.387°
HTM-20 index
-1461627296
Similar Worlds
Kepler-801 b
Sub-Neptune · K-type orange
Radius 2.00 R⊕ · 1,436.5 ly
Kepler-968 b
Sub-Neptune · K-type orange
Radius 2.00 R⊕ · 946.9 ly
Kepler-261 c
Sub-Neptune · K-type orange
Radius 2.00 R⊕ · 1,035.5 ly
Kepler-242 c
Sub-Neptune · K-type orange
Radius 2.00 R⊕ · 1,957.7 ly
HD 23472 b
Sub-Neptune · K-type orange
Radius 2.00 R⊕ · 127.3 ly
K2-101 b
Sub-Neptune · K-type orange
Radius 2.00 R⊕ · 614.2 ly