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 14.676 days
- Semi-major axis 0.1124 AU
- Equilibrium temperature 618 K (345 °C)
- Distance from Earth 614.25 light-years
- Earth Similarity Index 0.444
- Travel time at Voyager 1 speed 10,832,291 years
- Almost certainly tidally locked to its host star given the close orbit
K2-101 b 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 | K2-101 b | 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 175265494
Gaia DR2
Gaia DR2 661004400386393984
Gaia DR3
Gaia DR3 661004400386393984
System
K2-101
Percentile among Sub-Neptune cohort
Orbit & Habitability
Orbital Dynamics
Year Length
A year here lasts approximately 14.68 Earth days (4.0% of a terrestrial year) on a mildly elliptical path at a mean orbital distance of 0.1124 AU.
Transit Fingerprint
Depth
0.075 %
Duration
3.336 h
Impact parameter b
0.410
Rp / R★
0.024000
Transit midpoint (BJD)
2,457,152.6850
Photometric dip
Transit produces a flux drop of 749 ppm lasting ≈ 3.34 h.
Extended Orbital Architecture
Planet / star radius ratio
0.024000
Semi-major axis / stellar radius
31.820
Impact parameter (b)
0.410
Transit mid-time (BJD)
2,457,152.6850
Long. of periastron (ω)
0.00°
Angular separation (arcsec)
0.59700
Eq. Temperature
618K
(345 °C)
Insolation (S⊕)
—
Earth = 1.00
Earth Similarity (ESI)
0.444
0 = alien, 1 = Earth-identical
Insufficient insolation data — the surface is too hot to retain surface water. Close-orbiting tidally-locked around a cool host.
Discovery Paper
Primary reference
Mann et al. 2017Instrument
Kepler CCD Array
Publication
2017-02
Observation locale
Space
Discovery cohort
Planets confirmed in 2016 at K2 (12 shown).
Host System: K2-101
Spectral Class
K-type orange
Effective Temperature
4,927 K — cooler than the Sun (5,778 K)
Estimated Age
0.79 Gyr — younger than the Sun (4.6 Gyr)
Stellar Radius
0.760 R☉
Stellar Mass
0.820 M☉
Metallicity [Fe/H]
0.07
Extended Stellar Properties
Surface gravity (log g)
4.590 dex
Stellar density
2.920 g/cm³
Systemic radial velocity
34.31 km/s
Rotational v·sin i
3.90 km/s
Rotation period
10.60 days
Metallicity ratio
[Fe/H]
Multi-band Host Photometry — 17 bands
Astrometric Data
Parallax
5.282 mas
Total Proper Motion
38.698 mas/yr
PM Right Ascension
-36.59 mas/yr
PM Declination
-12.59 mas/yr
Galactic Cartesian (pc)
x = -0.612 · y = 0.721 · z = 0.324
Equatorial (J2000)
RA 130.34391° · Dec 18.93382°
Galactic ℓ, b
206.829° · 32.444°
Ecliptic λ, β
127.758° · 0.626°
HTM-20 index
-2144420086
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