Key parameters at a glance
- A radius of 1.33 Earth radii
- A mass of 2.33 Earth masses
- Surface gravity around 1.32 g
- An orbital period of 4.384 days
- Semi-major axis 0.0454 AU
- Distance from Earth 405.93 light-years
- Earth Similarity Index 0.936
- Travel time at Voyager 1 speed 7,158,526 years
- Almost certainly tidally locked to its host star given the close orbit
Context from the literature
K2-148b is a confirmed super-Earth, probably rocky, closely orbiting a small orange dwarf star. It is the innermost of three Super-Earths around the star K2-148, which is in a wide binary pair with the M0.5V red dwarf EPIC 220194953. K2-148b is the smallest planet of the system, at about a third larger than Earth, and could be terrestrial in nature. However, the three planets do not exhibit significant transit timing variations, implying that they could have relatively low masses. The planet was validated in early 2018 by Hirano et al. and is too hot for known life.
Excerpted from Wikipedia · full article
2 siblings around K2-148
K2-148 b shares its host star with 2 other confirmed planets. Side-by-side measurements below.
K2-148 b Planet Profile
Physical Specs
Classification
Planet Type
Super-Earth
Discovery
Size rank in cohort
Rank by radius
#1022of 1176
top 86.8%
This planet
1.33R⊕
Super-Earth median
1.60R⊕
Nearest-size peers
| Metric | Earth | K2-148 b | Jupiter |
|---|---|---|---|
| Radius (R⊕) | 1.00 | 1.33 | 11.21 |
| Mass (M⊕) | 1.00 | 2.33 | 317.83 |
| Density (g/cm³) | 5.51 | 5.44 | 1.33 |
| Surface Gravity (g) | 1.00 | 1.32 | 2.53 |
| Insolation (S⊕) | 1.00 | 48.80 | 0.037 |
Star Catalogue Identifiers
TIC
TIC 423358488
Gaia DR2
Gaia DR2 2536443724641751808
Gaia DR3
Gaia DR3 2536443724641751808
System
K2-148
Percentile among Super-Earth cohort
Orbit & Habitability
Orbital Dynamics
Year Length
A year here lasts approximately 4.38 Earth days (1.2% of a terrestrial year) at a mean orbital distance of 0.0454 AU.
Transit Fingerprint
Depth
0.032 %
Duration
1.776 h
Rp / R★
0.019300
Transit midpoint (BJD)
2,457,390.0596
Photometric dip
Transit produces a flux drop of 324 ppm lasting ≈ 1.78 h.
Extended Orbital Architecture
Planet / star radius ratio
0.019300
Semi-major axis / stellar radius
16.700
Transit mid-time (BJD)
2,457,390.0596
Angular separation (arcsec)
0.36500
Eq. Temperature
—
Insolation (S⊕)
48.80
Earth = 1.00
Earth Similarity (ESI)
0.936
0 = alien, 1 = Earth-identical
Inside the inner HZ boundary (too hot for liquid 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: K2-148
Spectral Class
K-type orange
Effective Temperature
4,079 K — cooler than the Sun (5,778 K)
Estimated Age
—
Stellar Radius
0.632 R☉
Stellar Mass
0.650 M☉
Metallicity [Fe/H]
-0.11
Extended Stellar Properties
Surface gravity (log g)
4.653 dex
Stellar density
2.943 g/cm³
Systemic radial velocity
1.52 km/s
Metallicity ratio
[Fe/H]
Multi-band Host Photometry — 12 bands
Astrometric Data
Parallax
8.006 mas
Total Proper Motion
45.323 mas/yr
PM Right Ascension
-38.70 mas/yr
PM Declination
-23.59 mas/yr
Galactic Cartesian (pc)
x = 0.968 · y = 0.251 · z = -0.003
Equatorial (J2000)
RA 14.51765° · Dec -0.19326°
Galactic ℓ, b
126.589° · -63.018°
Ecliptic λ, β
13.285° · -5.901°
HTM-20 index
-1835770589
Similar Worlds
K2-268 e
Super-Earth · K-type orange
Radius 1.33 R⊕ · 1,069.1 ly
Kepler-220 e
Super-Earth · K-type orange
Radius 1.33 R⊕ · 558.1 ly
Kepler-1190 b
Super-Earth · K-type orange
Radius 1.33 R⊕ · 1,117.1 ly
Kepler-707 b
Super-Earth · K-type orange
Radius 1.33 R⊕ · 1,930.1 ly
Kepler-1987 c
Super-Earth · K-type orange
Radius 1.33 R⊕ · 1,942.9 ly
K2-211 b
Super-Earth · K-type orange
Radius 1.33 R⊕ · 888.1 ly