Key parameters at a glance
- A radius of 13.30 Earth radii
- A mass of 797.75 Earth masses
- Surface gravity around 4.51 g
- An orbital period of 3,771.000 days
- Semi-major axis 4.1100 AU
- Distance from Earth 66.95 light-years
- Earth Similarity Index 0.382
- Travel time at Voyager 1 speed 1,180,641 years
1 sibling around GJ 328
GJ 328 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 |
|---|---|---|---|---|---|---|
| GJ 328 c | Neptune-like | 4.91 | 21.40 | 241.800 | — | 2023 |
| GJ 328 b this | Gas Giant | 13.30 | 797.75 | 3,771.000 | — | 2013 |
GJ 328 b Planet Profile
Physical Specs
Classification
Planet Type
Gas Giant
Discovery
Size rank in cohort
Rank by radius
#793of 1771
top 44.7%
This planet
13.30R⊕
Gas Giant median
13.52R⊕
Nearest-size peers
| Metric | Earth | GJ 328 b | Jupiter |
|---|---|---|---|
| Radius (R⊕) | 1.00 | 13.30 | 11.21 |
| Mass (M⊕) | 1.00 | 797.75 | 317.83 |
| Density (g/cm³) | 5.51 | 1.86 | 1.33 |
| Surface Gravity (g) | 1.00 | 4.51 | 2.53 |
| Insolation (S⊕) | 1.00 | — | 0.037 |
Alternative Mass Estimates
| Method | Value | Interpretation |
|---|---|---|
| Minimum mass (M sin i) | 797.749 M⊕ | Lower bound from radial-velocity fitting. |
Star Catalogue Identifiers
HIP
HIP 43790
TIC
TIC 265373654
Gaia DR2
Gaia DR2 577602496345490176
Gaia DR3
Gaia DR3 577602496345490176
System
GJ 328
Percentile among Gas Giant cohort
Orbit & Habitability
Orbital Dynamics
Year Length
A year here lasts about 10.32 Earth years on a mildly elliptical path at a mean orbital distance of 4.1100 AU.
Extended Orbital Architecture
RV semi-amplitude (K)
42.600 m/s
Transit mid-time (BJD)
2,456,177.0000
Long. of periastron (ω)
-76.20°
Angular separation (arcsec)
200.00000
Eq. Temperature
—
Insolation (S⊕)
—
Earth = 1.00
Earth Similarity (ESI)
0.382
0 = alien, 1 = Earth-identical
Discovery Paper
Primary reference
Robertson et al. 2013Instrument
High Resolution Spectrograph
Publication
2013-09
Observation locale
Ground
Discovery cohort
Planets confirmed in 2013 at McDonald Observatory (2 shown).
Host System: GJ 328
Spectral Class
M-type red dwarf
Effective Temperature
3,897 K — cooler than the Sun (5,778 K)
Estimated Age
—
Stellar Radius
0.630 R☉
Stellar Mass
0.650 M☉
Metallicity [Fe/H]
-0.06
Extended Stellar Properties
Surface gravity (log g)
4.640 dex
Stellar density
3.211 g/cm³
Activity index (log R'HK)
-4.679
Metallicity ratio
[Fe/H]
Multi-band Host Photometry — 17 bands
Astrometric Data
Parallax
48.688 mas
Total Proper Motion
1,046.927 mas/yr
PM Right Ascension
44.75 mas/yr
PM Declination
-1,045.97 mas/yr
Galactic Cartesian (pc)
x = -0.692 · y = 0.722 · z = 0.027
Equatorial (J2000)
RA 133.78195° · Dec 1.54200°
Galactic ℓ, b
226.710° · 27.999°
Ecliptic λ, β
135.785° · -15.212°
HTM-20 index
405678230
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