Key parameters at a glance

A radius of 14.20 Earth radii
A mass of 166.54 Earth masses
Surface gravity around 0.83 g
An orbital period of 2,560.198 days
Semi-major axis 3.7580 AU
Distance from Earth 201.55 light-years
Earth Similarity Index 0.257
Travel time at Voyager 1 speed 3,554,341 years

HD 217958 b Planet Profile

Physical Specs

Radius

14.20 R⊕

Radius (Jupiter)

1.270 R♃

Mass

166.54 M⊕

Mass (Jupiter)

0.524 M♃

Density

0.32 g/cm³

Surface Gravity

0.83 g (Earth)

Classification

Planet Type

Gas Giant

ESI Score 0.257

HZ Position Unknown

Controversial No

Discovery

Year 2022

Method Radial Velocity

Facility Multiple Observatories

Telescope Multiple Telescopes

Size rank in cohort

Rank by radius

#334of 1771

top 18.8%

This planet

14.20R⊕

Gas Giant median

13.52R⊕

Nearest-size peers

OGLE-2011-BLG-0251L b 14.20 R⊕ HIP 57274 c 14.20 R⊕ HD 187123 b 14.20 R⊕

Metric	Earth	HD 217958 b	Jupiter
Radius (R⊕)	1.00	14.20	11.21
Mass (M⊕)	1.00	166.54	317.83
Density (g/cm³)	5.51	0.32	1.33
Surface Gravity (g)	1.00	0.83	2.53
Insolation (S⊕)	1.00	—	0.037

Alternative Mass Estimates

Method	Value	Interpretation
Best measured mass	166.542 M⊕	Direct mass measurement (not derived).

Star Catalogue Identifiers

HD 217958

TIC

TIC 12973036

Gaia DR2

Gaia DR2 2382836143445509120

Gaia DR3

Gaia DR3 2382836143445759488

System

HD 217958

Percentile among Gas Giant cohort

Radius 14.200 R⊕ · percentile 79 / cohort 1771

Mass 166.542 M⊕ · percentile 14 / cohort 1747

Orbital period 2,560.20 d · percentile 87 / cohort 1533

Distance 61.80 pc · percentile 26 / cohort 1759

ESI 0.257 · percentile 47 / cohort 1771

Orbit & Habitability

Orbital Dynamics

Period

2,560.198 days

Semi-major axis

3.7580 AU

Eccentricity

0.156

Inclination

91.36 °

Year Length

A year here lasts about 7.01 Earth years on a mildly elliptical path at a mean orbital distance of 3.7580 AU.

Eq. Temperature

—

Insolation (S⊕)

—

Earth = 1.00

Earth Similarity (ESI)

0.257

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 217958

Spectral Class

G-type yellow (Sun-like)

Effective Temperature

5,931 K — hotter than the Sun (5,778 K)

Estimated Age

—

Stellar Radius

1.326 R☉

Stellar Mass

1.080 M☉

Metallicity [Fe/H]

0.29

Extended Stellar Properties

Surface gravity (log g)

4.226 dex

Stellar density

0.653 g/cm³

Metallicity ratio

[M/H]

Distance

61.80 parsec

Light-years 201.55 ly

V-band magnitude

8.05 mag

Voyager-speed travel 3,554,341 yr

Multi-band Host Photometry — 11 bands

Astrometric Data

Parallax

16.154 mas

Total Proper Motion

174.579 mas/yr

PM Right Ascension

-80.70 mas/yr

PM Declination

-154.81 mas/yr

Galactic Cartesian (pc)

x = 0.875 · y = -0.216 · z = -0.434

Equatorial (J2000)

RA 346.13658° · Dec -25.69178°

Galactic ℓ, b

30.273° · -66.068°

Ecliptic λ, β

337.041° · -18.172°

HTM-20 index

775994371