Key parameters at a glance
- A radius of 6.16 Earth radii
- A mass of 31.47 Earth masses
- Surface gravity around 0.83 g
- An orbital period of 799.520 days
- Semi-major axis 1.3730 AU
- Distance from Earth 109.34 light-years
- Earth Similarity Index 0.419
- Travel time at Voyager 1 speed 1,928,134 years
Context from the literature
HD 85390 b is an extrasolar planet which orbits the K-type main sequence star HD 85390, located approximately 106 light years away.
Excerpted from Wikipedia · full article
HD 85390 b Planet Profile
Physical Specs
Classification
Planet Type
Neptune-like
Discovery
Size rank in cohort
Rank by radius
#269of 574
top 46.7%
This planet
6.16R⊕
Neptune-like median
6.39R⊕
Nearest-size peers
| Metric | Earth | HD 85390 b | Jupiter |
|---|---|---|---|
| Radius (R⊕) | 1.00 | 6.16 | 11.21 |
| Mass (M⊕) | 1.00 | 31.47 | 317.83 |
| Density (g/cm³) | 5.51 | 0.74 | 1.33 |
| Surface Gravity (g) | 1.00 | 0.83 | 2.53 |
| Insolation (S⊕) | 1.00 | — | 0.037 |
Alternative Mass Estimates
| Method | Value | Interpretation |
|---|---|---|
| Minimum mass (M sin i) | 31.465 M⊕ | Lower bound from radial-velocity fitting. |
Star Catalogue Identifiers
HD
HD 85390
HIP
HIP 48235
TIC
TIC 446137194
Gaia DR2
Gaia DR2 5406324138654973824
Gaia DR3
Gaia DR3 5406324138654973824
System
HD 85390
Percentile among Neptune-like cohort
Orbit & Habitability
Orbital Dynamics
Year Length
A year here lasts about 2.19 Earth years on a highly eccentric trajectory at a mean orbital distance of 1.3730 AU.
Eq. Temperature
—
Insolation (S⊕)
—
Earth = 1.00
Earth Similarity (ESI)
0.419
0 = alien, 1 = Earth-identical
Discovery Paper
Primary reference
Mordasini et al. 2011Instrument
HARPS Spectrograph
Publication
2011-02
Observation locale
Ground
Discovery cohort
Planets confirmed in 2009 at La Silla Observatory (12 shown).
Host System: HD 85390
Spectral Class
K-type orange
Effective Temperature
5,186 K — cooler than the Sun (5,778 K)
Estimated Age
7.20 Gyr — older than the Sun (4.6 Gyr)
Stellar Radius
0.800 R☉
Stellar Mass
0.758 M☉
Metallicity [Fe/H]
-0.07
Extended Stellar Properties
Surface gravity (log g)
4.410 dex
Stellar density
2.215 g/cm³
Systemic radial velocity
33.03 km/s
Rotational v·sin i
4.00 km/s
Activity index (log R'HK)
-4.930
Metallicity ratio
[Fe/H]
Multi-band Host Photometry — 11 bands
Astrometric Data
Parallax
29.802 mas
Total Proper Motion
64.982 mas/yr
PM Right Ascension
24.36 mas/yr
PM Declination
-60.25 mas/yr
Galactic Cartesian (pc)
x = -0.545 · y = 0.347 · z = -0.764
Equatorial (J2000)
RA 147.51057° · Dec -49.79053°
Galactic ℓ, b
275.546° · 3.185°
Ecliptic λ, β
178.484° · -56.994°
HTM-20 index
-106714614
Similar Worlds
HD 156668 c
Neptune-like · K-type orange
Radius 6.17 R⊕ · 79.4 ly
TOI-4010 d
Neptune-like · K-type orange
Radius 6.18 R⊕ · 578.9 ly
K2-161 b
Neptune-like · K-type orange
Radius 6.12 R⊕ · 2,988.6 ly
TIC 365102760 b
Neptune-like · K-type orange
Radius 6.21 R⊕ · 1,811.9 ly
HD 115404 A b
Neptune-like · K-type orange
Radius 6.09 R⊕ · 35.8 ly
K2-39 b
Neptune-like · K-type orange
Radius 6.28 R⊕ · 1,002.8 ly