Key parameters at a glance

A radius of 12.80 Earth radii
A mass of 1,878.05 Earth masses
Surface gravity around 11.46 g
An orbital period of 17,202.194 days
Semi-major axis 13.1830 AU
Distance from Earth 89.89 light-years
Earth Similarity Index 0.438
Travel time at Voyager 1 speed 1,585,243 years

1 sibling around HD 155918

HD 155918 c 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
HD 155918 b	Sub-Neptune	2.67	7.63	1.876	—	2022
HD 155918 c this	Gas Giant	12.80	1,878.05	17,202.194	—	2022

HD 155918 c Planet Profile

Physical Specs

Radius

12.80 R⊕

Radius (Jupiter)

1.140 R♃

Mass

1,878.05 M⊕

Mass (Jupiter)

5.909 M♃

Density

4.92 g/cm³

Surface Gravity

11.46 g (Earth)

Classification

Planet Type

Gas Giant

ESI Score 0.438

HZ Position Unknown

Controversial No

Discovery

Year 2022

Method Radial Velocity

Facility Multiple Observatories

Telescope Multiple Telescopes

Size rank in cohort

Rank by radius

#1063of 1771

top 60.0%

This planet

12.80R⊕

Gas Giant median

13.52R⊕

Nearest-size peers

HD 240210 b 12.80 R⊕ HD 29985 b 12.80 R⊕ HD 148164 c 12.80 R⊕

Metric	Earth	HD 155918 c	Jupiter
Radius (R⊕)	1.00	12.80	11.21
Mass (M⊕)	1.00	1,878.05	317.83
Density (g/cm³)	5.51	4.92	1.33
Surface Gravity (g)	1.00	11.46	2.53
Insolation (S⊕)	1.00	—	0.037

Alternative Mass Estimates

Method	Value	Interpretation
Best measured mass	1,878.048 M⊕	Direct mass measurement (not derived).

Star Catalogue Identifiers

HD 155918

HIP

HIP 84988

TIC

TIC 311649327

Gaia DR2

Gaia DR2 5801950515627094400

Gaia DR3

Gaia DR3 5801950515627094400

System

HIP 84988

Percentile among Gas Giant cohort

Radius 12.800 R⊕ · percentile 37 / cohort 1771

Mass 1,878.048 M⊕ · percentile 78 / cohort 1747

Orbital period 17,202.19 d · percentile 97 / cohort 1533

Distance 27.56 pc · percentile 6 / cohort 1759

ESI 0.438 · percentile 97 / cohort 1771

Orbit & Habitability

Orbital Dynamics

Period

17,202.194 days

Semi-major axis

13.1830 AU

Eccentricity

0.071

Inclination

31.77 °

Year Length

A year here lasts about 47.10 Earth years on a nearly circular orbit at a mean orbital distance of 13.1830 AU.

Eq. Temperature

—

Insolation (S⊕)

—

Earth = 1.00

Earth Similarity (ESI)

0.438

0 = alien, 1 = Earth-identical

Discovery Paper

Primary reference

Feng et al. 2022

Instrument

Multiple Instruments

Publication

2022-09

Observation locale

Ground

Discovery cohort

Planets confirmed in 2022 at Multiple Observatories (12 shown).

Kepler-138 e · Rocky Terrestrial HD 93351 b · Super-Earth GJ 1002 b · Rocky Terrestrial GJ 2030 b · Sub-Neptune GJ 3929 c · Sub-Neptune HD 217786 c · Sub-Neptune GJ 1002 c · Rocky Terrestrial HD 155918 b · Sub-Neptune HD 213519 b · Sub-Neptune HD 191939 g · Sub-Neptune GJ 514 b · Sub-Neptune HD 12235 b · Sub-Neptune

Host System: HD 155918

Spectral Class

G-type yellow (Sun-like)

Effective Temperature

5,772 K — cooler than the Sun (5,778 K)

Estimated Age

12.30 Gyr — older than the Sun (4.6 Gyr)

Stellar Radius

1.019 R☉

Stellar Mass

1.030 M☉

Metallicity [Fe/H]

-0.66

Extended Stellar Properties

Surface gravity (log g)

4.435 dex

Stellar density

1.372 g/cm³

Systemic radial velocity

59.70 km/s

Rotational v·sin i

0.00 km/s

Metallicity ratio

[M/H]

Distance

27.56 parsec

Light-years 89.89 ly

V-band magnitude

7.00 mag

Voyager-speed travel 1,585,243 yr

Multi-band Host Photometry — 8 bands

Astrometric Data

Parallax

36.254 mas

Total Proper Motion

990.621 mas/yr

PM Right Ascension

-957.86 mas/yr

PM Declination

-252.66 mas/yr

Galactic Cartesian (pc)

x = -0.042 · y = -0.249 · z = -0.967

Equatorial (J2000)

RA 260.53640° · Dec -75.34924°

Galactic ℓ, b

317.430° · -20.834°

Ecliptic λ, β

266.120° · -52.037°

HTM-20 index

1407590339