Key parameters at a glance

A radius of 5.92 Earth radii
A mass of 29.40 Earth masses
Surface gravity around 0.84 g
An orbital period of 603.951 days
Semi-major axis 1.0304 AU
Distance from Earth 49.34 light-years
Earth Similarity Index 0.429
Travel time at Voyager 1 speed 870,155 years

2 siblings around GJ 163

GJ 163 d 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
GJ 163 b	Sub-Neptune	3.25	10.60	8.632	—	2013
GJ 163 c	Sub-Neptune	2.50	6.80	25.631	—	2013
GJ 163 d this	Neptune-like	5.92	29.40	603.951	—	2013

GJ 163 d Planet Profile

Physical Specs

Radius

5.92 R⊕

Radius (Jupiter)

0.528 R♃

Mass

29.40 M⊕

Mass (Jupiter)

0.093 M♃

Density

0.78 g/cm³

Surface Gravity

0.84 g (Earth)

Classification

Planet Type

Neptune-like

ESI Score 0.429

HZ Position Unknown

Controversial No

Discovery

Year 2013

Method Radial Velocity

Facility La Silla Observatory

Telescope 3.6 m ESO Telescope

Size rank in cohort

Rank by radius

#293of 574

top 50.9%

This planet

5.92R⊕

Neptune-like median

6.39R⊕

Nearest-size peers

Kepler-1755 b 5.92 R⊕ HD 134060 c 5.91 R⊕ TOI-4010 c 5.93 R⊕

Metric	Earth	GJ 163 d	Jupiter
Radius (R⊕)	1.00	5.92	11.21
Mass (M⊕)	1.00	29.40	317.83
Density (g/cm³)	5.51	0.78	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)	29.400 M⊕	Lower bound from radial-velocity fitting.

Star Catalogue Identifiers

HIP

HIP 19394

TIC

TIC 219221189

Gaia DR2

Gaia DR2 4780294722094459904

Gaia DR3

Gaia DR3 4780294722094459904

System

GJ 163

Percentile among Neptune-like cohort

Radius 5.920 R⊕ · percentile 49 / cohort 574

Mass 29.400 M⊕ · percentile 48 / cohort 574

Orbital period 603.95 d · percentile 96 / cohort 524

Distance 15.13 pc · percentile 4 / cohort 572

ESI 0.429 · percentile 78 / cohort 574

Orbit & Habitability

Orbital Dynamics

Period

603.951 days

Semi-major axis

1.0304 AU

Eccentricity

0.373

Inclination

— °

Year Length

A year here lasts about 1.65 Earth years on a highly eccentric trajectory at a mean orbital distance of 1.0304 AU.

Eq. Temperature

—

Insolation (S⊕)

—

Earth = 1.00

Earth Similarity (ESI)

0.429

0 = alien, 1 = Earth-identical

Discovery Paper

Primary reference

Bonfils et al. 2013

Instrument

HARPS Spectrograph

Publication

2013-08

Observation locale

Ground

Discovery cohort

Planets confirmed in 2013 at La Silla Observatory (10 shown).

GJ 667 C c · Super-Earth GJ 163 c · Sub-Neptune HD 40307 f · Sub-Neptune GJ 163 b · Sub-Neptune HD 109271 b · Neptune-like HD 109271 c · Neptune-like POTS-1 b · Gas Giant HD 65216 c · Gas Giant BD-06 1339 c · Neptune-like HD 103774 b · Gas Giant

Host System: GJ 163

Spectral Class

M-type red dwarf

Effective Temperature

3,500 K — cooler than the Sun (5,778 K)

Estimated Age

6.00 Gyr — older than the Sun (4.6 Gyr)

Stellar Radius

0.410 R☉

Stellar Mass

0.400 M☉

Metallicity [Fe/H]

0.10

Extended Stellar Properties

Surface gravity (log g)

4.818 dex

Stellar density

8.248 g/cm³

Systemic radial velocity

58.60 km/s

Metallicity ratio

[Fe/H]

Distance

15.13 parsec

Light-years 49.34 ly

V-band magnitude

11.79 mag

Voyager-speed travel 870,155 yr

Multi-band Host Photometry — 12 bands

Astrometric Data

Parallax

66.071 mas

Total Proper Motion

1,198.172 mas/yr

PM Right Ascension

1,046.14 mas/yr

PM Declination

584.13 mas/yr

Galactic Cartesian (pc)

x = 0.277 · y = 0.528 · z = -0.803

Equatorial (J2000)

RA 62.32284° · Dec -53.37118°

Galactic ℓ, b

262.777° · -45.320°

Ecliptic λ, β

30.848° · -71.167°

HTM-20 index

-1724147858