Key parameters at a glance
- A radius of 5.83 Earth radii
- A mass of 28.60 Earth masses
- Surface gravity around 0.84 g
- An orbital period of 47.840 days
- Semi-major axis 0.2500 AU
- Distance from Earth 186.39 light-years
- Earth Similarity Index 0.433
- Travel time at Voyager 1 speed 3,286,918 years
- Almost certainly tidally locked to its host star given the close orbit
Context from the literature
HD 103197 b is an extrasolar planet which orbits the K-type main sequence star HD 103197, located approximately 170 light years away. It is outside of the habitable zone, and as such is unlikely to have liquid water on its moons, if there are any.
Excerpted from Wikipedia · full article
HD 103197 b Planet Profile
Physical Specs
Classification
Planet Type
Neptune-like
Discovery
Size rank in cohort
Rank by radius
#297of 574
top 51.6%
This planet
5.83R⊕
Neptune-like median
6.39R⊕
Nearest-size peers
| Metric | Earth | HD 103197 b | Jupiter |
|---|---|---|---|
| Radius (R⊕) | 1.00 | 5.83 | 11.21 |
| Mass (M⊕) | 1.00 | 28.60 | 317.83 |
| Density (g/cm³) | 5.51 | 0.79 | 1.33 |
| Surface Gravity (g) | 1.00 | 0.84 | 2.53 |
| Insolation (S⊕) | 1.00 | — | 0.037 |
Alternative Mass Estimates
| Method | Value | Interpretation |
|---|---|---|
| Minimum mass (M sin i) | 28.605 M⊕ | Lower bound from radial-velocity fitting. |
Star Catalogue Identifiers
HD
HD 103197
HIP
HIP 57931
TIC
TIC 400806831
Gaia DR2
Gaia DR2 5370827127297364480
Gaia DR3
Gaia DR3 5370827127297364480
System
HD 103197
Percentile among Neptune-like cohort
Orbit & Habitability
Orbital Dynamics
Year Length
A year here lasts approximately 47.84 Earth days (13.1% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.2500 AU.
Eq. Temperature
—
Insolation (S⊕)
—
Earth = 1.00
Earth Similarity (ESI)
0.433
0 = alien, 1 = Earth-identical
Insufficient insolation data. Close-orbiting tidally-locked around a cool host.
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 103197
Spectral Class
K-type orange
Effective Temperature
5,250 K — cooler than the Sun (5,778 K)
Estimated Age
9.10 Gyr — older than the Sun (4.6 Gyr)
Stellar Radius
0.880 R☉
Stellar Mass
0.800 M☉
Metallicity [Fe/H]
0.22
Extended Stellar Properties
Surface gravity (log g)
4.450 dex
Stellar density
1.742 g/cm³
Systemic radial velocity
-4.55 km/s
Metallicity ratio
[Fe/H]
Multi-band Host Photometry — 11 bands
Astrometric Data
Parallax
17.470 mas
Total Proper Motion
81.257 mas/yr
PM Right Ascension
-80.94 mas/yr
PM Declination
7.19 mas/yr
Galactic Cartesian (pc)
x = -0.639 · y = 0.020 · z = -0.769
Equatorial (J2000)
RA 178.22020° · Dec -50.29279°
Galactic ℓ, b
293.448° · 11.498°
Ecliptic λ, β
204.258° · -45.539°
HTM-20 index
-1953956930
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