Key parameters at a glance
- A radius of 1.58 Earth radii
- A mass of 3.12 Earth masses
- Surface gravity around 1.25 g
- An orbital period of 2.859 days
- Distance from Earth 936.68 light-years
- Earth Similarity Index 0.873
- Travel time at Voyager 1 speed 16,518,367 years
- Almost certainly tidally locked to its host star given the close orbit
K2-191 b Planet Profile
Physical Specs
Classification
Planet Type
Super-Earth
Discovery
Size rank in cohort
Rank by radius
#615of 1176
top 52.2%
This planet
1.58R⊕
Super-Earth median
1.60R⊕
Nearest-size peers
| Metric | Earth | K2-191 b | Jupiter |
|---|---|---|---|
| Radius (R⊕) | 1.00 | 1.58 | 11.21 |
| Mass (M⊕) | 1.00 | 3.12 | 317.83 |
| Density (g/cm³) | 5.51 | 4.36 | 1.33 |
| Surface Gravity (g) | 1.00 | 1.25 | 2.53 |
| Insolation (S⊕) | 1.00 | — | 0.037 |
Star Catalogue Identifiers
TIC
TIC 335102224
Gaia DR2
Gaia DR2 3610048418926172032
Gaia DR3
Gaia DR3 3610048418926172032
System
K2-191
Percentile among Super-Earth cohort
Orbit & Habitability
Orbital Dynamics
Year Length
A year here lasts approximately 2.86 Earth days (0.8% of a terrestrial year).
Transit Fingerprint
Depth
0.031 %
Duration
2.232 h
Impact parameter b
0.188
Rp / R★
0.017239
Transit midpoint (BJD)
2,457,219.5570
Photometric dip
Transit produces a flux drop of 308 ppm lasting ≈ 2.23 h.
Extended Orbital Architecture
Planet / star radius ratio
0.017239
Semi-major axis / stellar radius
8.603
Impact parameter (b)
0.188
Transit mid-time (BJD)
2,457,219.5570
Eq. Temperature
—
Insolation (S⊕)
—
Earth = 1.00
Earth Similarity (ESI)
0.873
0 = alien, 1 = Earth-identical
Insufficient insolation data. Close-orbiting tidally-locked around a cool host.
Discovery Paper
Primary reference
Mayo et al. 2018Instrument
Kepler CCD Array
Publication
2018-03
Observation locale
Space
Discovery cohort
Planets confirmed in 2018 at K2 (12 shown).
Host System: K2-191
Spectral Class
K-type orange
Effective Temperature
5,176 K — cooler than the Sun (5,778 K)
Estimated Age
—
Stellar Radius
0.840 R☉
Stellar Mass
0.901 M☉
Metallicity [Fe/H]
0.31
Extended Stellar Properties
Surface gravity (log g)
4.570 dex
Stellar density
1.655 g/cm³
Systemic radial velocity
-7.23 km/s
Metallicity ratio
[Fe/H]
Multi-band Host Photometry — 12 bands
Astrometric Data
Parallax
3.453 mas
Total Proper Motion
26.579 mas/yr
PM Right Ascension
-6.26 mas/yr
PM Declination
-25.83 mas/yr
Galactic Cartesian (pc)
x = -0.906 · y = -0.360 · z = -0.222
Equatorial (J2000)
RA 201.63914° · Dec -12.80667°
Galactic ℓ, b
316.089° · 49.166°
Ecliptic λ, β
204.758° · -3.459°
HTM-20 index
381510342
Similar Worlds
K2-68 b
Super-Earth · K-type orange
Radius 1.58 R⊕ · 550.1 ly
Kepler-386 c
Super-Earth · K-type orange
Radius 1.58 R⊕ · 2,878.2 ly
Kepler-2000 c
Super-Earth · K-type orange
Radius 1.57 R⊕ · 1,045.6 ly
Kepler-220 c
Super-Earth · K-type orange
Radius 1.57 R⊕ · 558.1 ly
K2-50 b
Super-Earth · K-type orange
Radius 1.59 R⊕ · 839.7 ly
Kepler-55 d
Super-Earth · K-type orange
Radius 1.59 R⊕ · 1,887.8 ly