Key parameters at a glance

A radius of 13.50 Earth radii
A mass of 511.71 Earth masses
Surface gravity around 2.81 g
An orbital period of 1,173.000 days
Semi-major axis 2.3060 AU
Distance from Earth 182.17 light-years
Earth Similarity Index 0.348
Travel time at Voyager 1 speed 3,212,560 years

HD 221585 b Planet Profile

Physical Specs

Radius

13.50 R⊕

Radius (Jupiter)

1.210 R♃

Mass

511.71 M⊕

Mass (Jupiter)

1.610 M♃

Density

1.14 g/cm³

Surface Gravity

2.81 g (Earth)

Classification

Planet Type

Gas Giant

ESI Score 0.348

HZ Position Unknown

Controversial No

Discovery

Year 2016

Method Radial Velocity

Facility Haute-Provence Observatory

Telescope 1.93 m Telescope

Size rank in cohort

Rank by radius

#671of 1771

top 37.8%

This planet

13.50R⊕

Gas Giant median

13.52R⊕

Nearest-size peers

HD 45350 b 13.50 R⊕ HD 82943 b 13.50 R⊕ HD 27442 b 13.50 R⊕

Metric	Earth	HD 221585 b	Jupiter
Radius (R⊕)	1.00	13.50	11.21
Mass (M⊕)	1.00	511.71	317.83
Density (g/cm³)	5.51	1.14	1.33
Surface Gravity (g)	1.00	2.81	2.53
Insolation (S⊕)	1.00	—	0.037

Alternative Mass Estimates

Method	Value	Interpretation
Minimum mass (M sin i)	511.706 M⊕	Lower bound from radial-velocity fitting.

Star Catalogue Identifiers

HD 221585

HIP

HIP 116221

TIC

TIC 270730826

Gaia DR2

Gaia DR2 2016655237613545728

Gaia DR3

Gaia DR3 2016655237613545728

System

HD 221585

Percentile among Gas Giant cohort

Radius 13.500 R⊕ · percentile 59 / cohort 1771

Mass 511.706 M⊕ · percentile 49 / cohort 1747

Orbital period 1,173.00 d · percentile 79 / cohort 1533

Distance 55.85 pc · percentile 23 / cohort 1759

ESI 0.348 · percentile 70 / cohort 1771

Orbit & Habitability

Orbital Dynamics

Period

1,173.000 days

Semi-major axis

2.3060 AU

Eccentricity

0.123

Inclination

— °

Year Length

A year here lasts about 3.21 Earth years on a mildly elliptical path at a mean orbital distance of 2.3060 AU.

Eq. Temperature

—

Insolation (S⊕)

—

Earth = 1.00

Earth Similarity (ESI)

0.348

0 = alien, 1 = Earth-identical

Discovery Paper

Primary reference

D Iacute Az et al. 2016

Instrument

SOPHIE Spectrograph

Publication

2016-07

Observation locale

Ground

Discovery cohort

Planets confirmed in 2016 at Haute-Provence Observatory (10 shown).

HD 35759 b · Gas Giant HD 220842 b · Gas Giant HD 12484 b · Gas Giant HD 191806 b · Gas Giant HIP 109600 b · Gas Giant HIP 109384 b · Gas Giant HD 143105 b · Gas Giant HD 214823 b · Gas Giant HIP 65407 c · Gas Giant HIP 65407 b · Gas Giant

Host System: HD 221585

Spectral Class

G-type yellow (Sun-like)

Effective Temperature

5,620 K — cooler than the Sun (5,778 K)

Estimated Age

6.20 Gyr — older than the Sun (4.6 Gyr)

Stellar Radius

1.851 R☉

Stellar Mass

1.190 M☉

Metallicity [Fe/H]

0.29

Extended Stellar Properties

Surface gravity (log g)

4.050 dex

Stellar density

0.216 g/cm³

Systemic radial velocity

6.43 km/s

Rotational v·sin i

3.70 km/s

Rotation period

33.30 days

Metallicity ratio

[Fe/H]

Distance

55.85 parsec

Light-years 182.17 ly

V-band magnitude

7.46 mag

Voyager-speed travel 3,212,560 yr

Multi-band Host Photometry — 7 bands

Astrometric Data

Parallax

17.875 mas

Total Proper Motion

440.224 mas/yr

PM Right Ascension

439.15 mas/yr

PM Declination

30.76 mas/yr

Galactic Cartesian (pc)

x = 0.448 · y = -0.053 · z = 0.892

Equatorial (J2000)

RA 353.22938° · Dec 63.15561°

Galactic ℓ, b

114.203° · 1.622°

Ecliptic λ, β

34.311° · 57.118°

HTM-20 index

-908961445