Key parameters at a glance
- A radius of 2.06 Earth radii
- A mass of 4.88 Earth masses
- Surface gravity around 1.15 g
- An orbital period of 7.340 days
- Semi-major axis 0.0652 AU
- Equilibrium temperature 957 K (684 °C)
- Distance from Earth 55.13 light-years
- Earth Similarity Index 0.282
- Travel time at Voyager 1 speed 972,295 years
- Almost certainly tidally locked to its host star given the close orbit
2 siblings around HD 48948
HD 48948 b shares its host star with 2 other confirmed planets. Side-by-side measurements below.
| Planet | Type | Radius (R⊕) | Mass (M⊕) | Period (d) | Eq. T (K) | Year |
|---|---|---|---|---|---|---|
| HD 48948 b this | Sub-Neptune | 2.06 | 4.88 | 7.340 | 957 | 2024 |
| HD 48948 c | Sub-Neptune | 2.60 | 7.27 | 38.060 | 553 | 2024 |
| HD 48948 d | Sub-Neptune | 3.24 | 10.59 | 151.920 | 349 | 2024 |
HD 48948 b Planet Profile
Physical Specs
Classification
Planet Type
Sub-Neptune
Discovery
Size rank in cohort
Rank by radius
#1875of 1978
top 94.7%
This planet
2.06R⊕
Sub-Neptune median
2.71R⊕
Nearest-size peers
| Metric | Earth | HD 48948 b | Jupiter |
|---|---|---|---|
| Radius (R⊕) | 1.00 | 2.06 | 11.21 |
| Mass (M⊕) | 1.00 | 4.88 | 317.83 |
| Density (g/cm³) | 5.51 | 3.07 | 1.33 |
| Surface Gravity (g) | 1.00 | 1.15 | 2.53 |
| Insolation (S⊕) | 1.00 | 138.85 | 0.037 |
Alternative Mass Estimates
| Method | Value | Interpretation |
|---|---|---|
| Minimum mass (M sin i) | 4.880 M⊕ | Lower bound from radial-velocity fitting. |
Star Catalogue Identifiers
HD
HD 48948
HIP
HIP 32769
TIC
TIC 88228576
Gaia DR2
Gaia DR2 1003351437484254464
Gaia DR3
Gaia DR3 1003351437484254464
System
HD 48948
Percentile among Sub-Neptune cohort
Orbit & Habitability
Orbital Dynamics
Year Length
A year here lasts approximately 7.34 Earth days (2.0% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.0652 AU.
Extended Orbital Architecture
Semi-major axis / stellar radius
20.650
RV semi-amplitude (K)
2.280 m/s
Long. of periastron (ω)
39.00°
Angular separation (arcsec)
3.86000
Eq. Temperature
957K
(684 °C)
Insolation (S⊕)
138.85
Earth = 1.00
Earth Similarity (ESI)
0.282
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
Dalal et al. 2024Instrument
HARPS-N Spectrograph
Publication
2024-07
Observation locale
Ground
Discovery cohort
Planets confirmed in 2024 at Roque de los Muchachos Observatory (2 shown).
Host System: HD 48948
Spectral Class
K-type orange
Effective Temperature
4,593 K — cooler than the Sun (5,778 K)
Estimated Age
11.48 Gyr — older than the Sun (4.6 Gyr)
Stellar Radius
0.679 R☉
Stellar Mass
0.686 M☉
Metallicity [Fe/H]
-0.21
Extended Stellar Properties
Surface gravity (log g)
4.610 dex
Stellar density
3.073 g/cm³
Systemic radial velocity
-53.00 km/s
Rotational v·sin i
2.00 km/s
Rotation period
43.45 days
Activity index (log R'HK)
-4.915
Metallicity ratio
[Fe/H]
Multi-band Host Photometry — 7 bands
Astrometric Data
Parallax
59.128 mas
Total Proper Motion
482.492 mas/yr
PM Right Ascension
253.25 mas/yr
PM Declination
410.69 mas/yr
Galactic Cartesian (pc)
x = -0.107 · y = 0.483 · z = 0.869
Equatorial (J2000)
RA 102.48981° · Dec 60.33731°
Galactic ℓ, b
155.499° · 23.165°
Ecliptic λ, β
97.722° · 37.233°
HTM-20 index
1077153194
Similar Worlds
Kepler-913 b
Sub-Neptune · K-type orange
Radius 2.06 R⊕ · 3,234.2 ly
K2-321 b
Sub-Neptune · K-type orange
Radius 2.05 R⊕ · 253.4 ly
Kepler-988 b
Sub-Neptune · K-type orange
Radius 2.07 R⊕ · 994.4 ly
TOI-262 b
Sub-Neptune · K-type orange
Radius 2.07 R⊕ · 143.3 ly
Kepler-161 c
Sub-Neptune · K-type orange
Radius 2.05 R⊕ · 1,417.6 ly
TOI-712 b
Sub-Neptune · K-type orange
Radius 2.05 R⊕ · 191.2 ly