Key parameters at a glance
- A radius of 2.26 Earth radii
- A mass of 5.74 Earth masses
- Surface gravity around 1.12 g
- An orbital period of 6.293 days
- Distance from Earth 654.68 light-years
- Earth Similarity Index 0.741
- Travel time at Voyager 1 speed 11,545,337 years
- Almost certainly tidally locked to its host star given the close orbit
K2-401 b Planet Profile
Physical Specs
Classification
Planet Type
Sub-Neptune
Discovery
Size rank in cohort
Rank by radius
#1571of 1978
top 79.4%
This planet
2.26R⊕
Sub-Neptune median
2.71R⊕
Nearest-size peers
| Metric | Earth | K2-401 b | Jupiter |
|---|---|---|---|
| Radius (R⊕) | 1.00 | 2.26 | 11.21 |
| Mass (M⊕) | 1.00 | 5.74 | 317.83 |
| Density (g/cm³) | 5.51 | 2.73 | 1.33 |
| Surface Gravity (g) | 1.00 | 1.12 | 2.53 |
| Insolation (S⊕) | 1.00 | — | 0.037 |
Star Catalogue Identifiers
TIC
TIC 345063080
Gaia DR2
Gaia DR2 3860043690538404992
Gaia DR3
Gaia DR3 3860043690538404992
System
K2-401
Percentile among Sub-Neptune cohort
Orbit & Habitability
Orbital Dynamics
Year Length
A year here lasts approximately 6.29 Earth days (1.7% of a terrestrial year).
Transit Fingerprint
Duration
1.900 h
Impact parameter b
0.621
Rp / R★
0.030600
Transit midpoint (BJD)
2,457,906.9531
Extended Orbital Architecture
Planet / star radius ratio
0.030600
Semi-major axis / stellar radius
20.970
Impact parameter (b)
0.621
Transit mid-time (BJD)
2,457,906.9531
Eq. Temperature
—
Insolation (S⊕)
—
Earth = 1.00
Earth Similarity (ESI)
0.741
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: K2-401
Spectral Class
K-type orange
Effective Temperature
4,213 K — cooler than the Sun (5,778 K)
Estimated Age
—
Stellar Radius
0.675 R☉
Stellar Mass
0.870 M☉
Metallicity [Fe/H]
-0.10
Extended Stellar Properties
Surface gravity (log g)
4.719 dex
Stellar density
3.033 g/cm³
Metallicity ratio
[Fe/H]
Multi-band Host Photometry — 17 bands
Astrometric Data
Parallax
4.953 mas
Total Proper Motion
79.718 mas/yr
PM Right Ascension
18.81 mas/yr
PM Declination
-77.47 mas/yr
Galactic Cartesian (pc)
x = -0.904 · y = 0.422 · z = 0.069
Equatorial (J2000)
RA 154.98760° · Dec 3.95483°
Galactic ℓ, b
238.856° · 47.081°
Ecliptic λ, β
155.369° · -5.999°
HTM-20 index
1507432400
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
Radius 2.26 R⊕ · 344.4 ly
Kepler-1261 b
Sub-Neptune · K-type orange
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
Radius 2.26 R⊕ · 2,242.7 ly
Kepler-1388 c
Sub-Neptune · K-type orange
Radius 2.26 R⊕ · 1,480.1 ly