Key parameters at a glance
- A radius of 1.99 Earth radii
- A mass of 4.62 Earth masses
- Surface gravity around 1.17 g
- An orbital period of 3.676 days
- Semi-major axis 0.0405 AU
- Equilibrium temperature 715 K (442 °C)
- Distance from Earth 421.90 light-years
- Earth Similarity Index 0.386
- Travel time at Voyager 1 speed 7,440,248 years
- Almost certainly tidally locked to its host star given the close orbit
1 sibling around K2-154
K2-154 b shares its host star with 1 other confirmed planet. Side-by-side measurements below.
| Planet | Type | Radius (R⊕) | Mass (M⊕) | Period (d) | Eq. T (K) | Year |
|---|---|---|---|---|---|---|
| K2-154 b this | Super-Earth | 1.99 | 4.62 | 3.676 | 715 | 2018 |
| K2-154 c | Sub-Neptune | 2.07 | 4.94 | 7.955 | 552 | 2018 |
K2-154 b Planet Profile
Physical Specs
Classification
Planet Type
Super-Earth
Discovery
Size rank in cohort
Rank by radius
#4of 1176
top 0.3%
This planet
1.99R⊕
Super-Earth median
1.60R⊕
Nearest-size peers
| Metric | Earth | K2-154 b | Jupiter |
|---|---|---|---|
| Radius (R⊕) | 1.00 | 1.99 | 11.21 |
| Mass (M⊕) | 1.00 | 4.62 | 317.83 |
| Density (g/cm³) | 5.51 | 3.22 | 1.33 |
| Surface Gravity (g) | 1.00 | 1.17 | 2.53 |
| Insolation (S⊕) | 1.00 | 57.50 | 0.037 |
Star Catalogue Identifiers
TIC
TIC 175371068
Gaia DR2
Gaia DR2 3683121446312149504
Gaia DR3
Gaia DR3 3683121446312149504
System
K2-154
Percentile among Super-Earth cohort
Orbit & Habitability
Orbital Dynamics
Year Length
A year here lasts approximately 3.68 Earth days (1.0% of a terrestrial year) at a mean orbital distance of 0.0405 AU.
Transit Fingerprint
Depth
0.110 %
Duration
1.700 h
Impact parameter b
0.440
Rp / R★
0.028800
Transit midpoint (BJD)
2,457,585.0533
Photometric dip
Transit produces a flux drop of 1,100 ppm lasting ≈ 1.70 h.
Extended Orbital Architecture
Planet / star radius ratio
0.028800
Semi-major axis / stellar radius
14.500
Impact parameter (b)
0.440
Transit mid-time (BJD)
2,457,585.0533
Angular separation (arcsec)
0.31300
Eq. Temperature
715K
(442 °C)
Insolation (S⊕)
57.50
Earth = 1.00
Earth Similarity (ESI)
0.386
0 = alien, 1 = Earth-identical
Inside the inner HZ boundary (too hot for liquid water) — the surface is too hot to retain surface water. Close-orbiting tidally-locked around a cool host.
Discovery Paper
Primary reference
Hirano et al. 2018Instrument
Kepler CCD Array
Publication
2018-03
Observation locale
Space
Discovery cohort
Planets confirmed in 2018 at K2 (12 shown).
Host System: K2-154
Spectral Class
M-type red dwarf
Effective Temperature
4,097 K — cooler than the Sun (5,778 K)
Estimated Age
—
Stellar Radius
0.630 R☉
Stellar Mass
0.650 M☉
Metallicity [Fe/H]
0.21
Extended Stellar Properties
Surface gravity (log g)
4.650 dex
Stellar density
3.250 g/cm³
Systemic radial velocity
14.30 km/s
Metallicity ratio
[Fe/H]
Multi-band Host Photometry — 17 bands
Astrometric Data
Parallax
7.702 mas
Total Proper Motion
34.576 mas/yr
PM Right Ascension
0.75 mas/yr
PM Declination
-34.57 mas/yr
Galactic Cartesian (pc)
x = -0.987 · y = -0.156 · z = -0.047
Equatorial (J2000)
RA 189.00152° · Dec -2.66962°
Galactic ℓ, b
295.214° · 59.971°
Ecliptic λ, β
189.316° · 1.114°
HTM-20 index
295760025
Similar Worlds
TOI-521 b
Super-Earth · M-type red dwarf
Radius 1.98 R⊕ · 198.8 ly
Kepler-267 b
Super-Earth · M-type red dwarf
Radius 1.98 R⊕ · 864.3 ly
TOI-1266 c
Super-Earth · M-type red dwarf
Radius 1.98 R⊕ · 117.5 ly
Kepler-28 b
Super-Earth · M-type red dwarf
Radius 1.96 R⊕ · 1,429.7 ly
Kepler-52 d
Super-Earth · M-type red dwarf
Radius 1.95 R⊕ · 1,048.7 ly
Kepler-83 d
Super-Earth · M-type red dwarf
Radius 1.94 R⊕ · 1,306.0 ly