Key parameters at a glance
- A radius of 1.75 Earth radii
- A mass of 8.00 Earth masses
- Surface gravity around 2.61 g
- An orbital period of 2.175 days
- Semi-major axis 0.0280 AU
- Equilibrium temperature 1,103 K (830 °C)
- Distance from Earth 376.58 light-years
- Earth Similarity Index 0.244
- Travel time at Voyager 1 speed 6,641,040 years
- Almost certainly tidally locked to its host star given the close orbit
K2-216 b Planet Profile
Physical Specs
Classification
Planet Type
Super-Earth
Discovery
Size rank in cohort
Rank by radius
#326of 1176
top 27.6%
This planet
1.75R⊕
Super-Earth median
1.60R⊕
Nearest-size peers
| Metric | Earth | K2-216 b | Jupiter |
|---|---|---|---|
| Radius (R⊕) | 1.00 | 1.75 | 11.21 |
| Mass (M⊕) | 1.00 | 8.00 | 317.83 |
| Density (g/cm³) | 5.51 | 8.20 | 1.33 |
| Surface Gravity (g) | 1.00 | 2.61 | 2.53 |
| Insolation (S⊕) | 1.00 | 248.00 | 0.037 |
Alternative Mass Estimates
| Method | Value | Interpretation |
|---|---|---|
| Best measured mass | 8.000 M⊕ | Direct mass measurement (not derived). |
Star Catalogue Identifiers
TIC
TIC 418761354
Gaia DR2
Gaia DR2 2556231154370582400
Gaia DR3
Gaia DR3 2556231154370582400
System
K2-216
Percentile among Super-Earth cohort
Orbit & Habitability
Orbital Dynamics
Year Length
A year here lasts approximately 2.17 Earth days (0.6% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.0280 AU.
Transit Fingerprint
Depth
0.056 %
Duration
1.840 h
Impact parameter b
0.450
Rp / R★
0.022100
Transit midpoint (BJD)
2,457,394.0417
Photometric dip
Transit produces a flux drop of 560 ppm lasting ≈ 1.84 h.
Extended Orbital Architecture
Planet / star radius ratio
0.022100
Semi-major axis / stellar radius
8.300
Impact parameter (b)
0.450
RV semi-amplitude (K)
5.000 m/s
Transit mid-time (BJD)
2,457,394.0417
Angular separation (arcsec)
0.24300
Eq. Temperature
1,103K
(830 °C)
Insolation (S⊕)
248.00
Earth = 1.00
Earth Similarity (ESI)
0.244
0 = alien, 1 = Earth-identical
Inside the inner HZ boundary (too hot for liquid water) — the dayside is scorched. Close-orbiting tidally-locked around a cool host.
Detection Signatures
Transit photometry
A transit dip has been observed from at least one telescope.
Radial velocity
Stellar wobble has been measured spectroscopically.
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: K2-216
Spectral Class
K-type orange
Effective Temperature
4,503 K — cooler than the Sun (5,778 K)
Estimated Age
—
Stellar Radius
0.720 R☉
Stellar Mass
0.700 M☉
Metallicity [Fe/H]
0.00
Extended Stellar Properties
Surface gravity (log g)
4.570 dex
Stellar density
2.300 g/cm³
Systemic radial velocity
-26.16 km/s
Rotational v·sin i
1.80 km/s
Activity index (log R'HK)
-4.627
Metallicity ratio
[Fe/H]
Multi-band Host Photometry — 12 bands
Astrometric Data
Parallax
8.632 mas
Total Proper Motion
10.786 mas/yr
PM Right Ascension
-1.97 mas/yr
PM Declination
10.60 mas/yr
Galactic Cartesian (pc)
x = 0.974 · y = 0.198 · z = 0.111
Equatorial (J2000)
RA 11.48024° · Dec 6.34703°
Galactic ℓ, b
120.448° · -56.498°
Ecliptic λ, β
13.030° · 1.303°
HTM-20 index
-2128095076
Similar Worlds
Kepler-245 e
Super-Earth · K-type orange
Radius 1.75 R⊕ · 2,809.9 ly
Kepler-124 c
Super-Earth · K-type orange
Radius 1.75 R⊕ · 1,370.0 ly
TOI-178 c
Super-Earth · K-type orange
Radius 1.75 R⊕ · 204.5 ly
Kepler-1062 b
Super-Earth · K-type orange
Radius 1.76 R⊕ · 1,296.3 ly
Kepler-1814 c
Super-Earth · K-type orange
Radius 1.76 R⊕ · 2,369.0 ly
Kepler-755 b
Super-Earth · K-type orange
Radius 1.76 R⊕ · 1,301.5 ly