Key parameters at a glance

A radius of 13.40 Earth radii
A mass of 578.43 Earth masses
Surface gravity around 3.22 g
An orbital period of 192.900 days
Semi-major axis 0.6540 AU
Distance from Earth 164.22 light-years
Earth Similarity Index 0.359
Travel time at Voyager 1 speed 2,896,029 years

1 sibling around HD 9446

HD 9446 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 9446 b	Gas Giant	14.00	222.47	30.052	—	2009
HD 9446 c this	Gas Giant	13.40	578.43	192.900	—	2009

HD 9446 c Planet Profile

Physical Specs

Radius

13.40 R⊕

Radius (Jupiter)

1.200 R♃

Mass

578.43 M⊕

Mass (Jupiter)

1.820 M♃

Density

1.32 g/cm³

Surface Gravity

3.22 g (Earth)

Classification

Planet Type

Gas Giant

ESI Score 0.359

HZ Position Unknown

Controversial No

Discovery

Year 2009

Method Radial Velocity

Facility Haute-Provence Observatory

Telescope 1.93 m Telescope

Size rank in cohort

Rank by radius

#730of 1771

top 41.2%

This planet

13.40R⊕

Gas Giant median

13.52R⊕

Nearest-size peers

HD 114783 c 13.40 R⊕ HIP 79431 b 13.40 R⊕ HD 68988 b 13.40 R⊕

Metric	Earth	HD 9446 c	Jupiter
Radius (R⊕)	1.00	13.40	11.21
Mass (M⊕)	1.00	578.43	317.83
Density (g/cm³)	5.51	1.32	1.33
Surface Gravity (g)	1.00	3.22	2.53
Insolation (S⊕)	1.00	—	0.037

Alternative Mass Estimates

Method	Value	Interpretation
Minimum mass (M sin i)	578.426 M⊕	Lower bound from radial-velocity fitting.

Star Catalogue Identifiers

HD 9446

HIP

HIP 7245

TIC

TIC 18277196

Gaia DR2

Gaia DR2 302956655074266112

Gaia DR3

Gaia DR3 302956655074266112

System

HD 9446

Percentile among Gas Giant cohort

Radius 13.400 R⊕ · percentile 56 / cohort 1771

Mass 578.426 M⊕ · percentile 52 / cohort 1747

Orbital period 192.90 d · percentile 57 / cohort 1533

Distance 50.35 pc · percentile 20 / cohort 1759

ESI 0.359 · percentile 73 / cohort 1771

Orbit & Habitability

Orbital Dynamics

Period

192.900 days

Semi-major axis

0.6540 AU

Eccentricity

0.060

Inclination

— °

Year Length

A year here lasts approximately 192.90 Earth days (52.8% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.6540 AU.

Eq. Temperature

—

Insolation (S⊕)

—

Earth = 1.00

Earth Similarity (ESI)

0.359

0 = alien, 1 = Earth-identical

Discovery Paper

Primary reference

Hebrard et al. 2010

Instrument

SOPHIE Spectrograph

Publication

2010-04

Observation locale

Ground

Host System: HD 9446

Spectral Class

G-type yellow (Sun-like)

Effective Temperature

5,793 K — hotter than the Sun (5,778 K)

Estimated Age

—

Stellar Radius

1.000 R☉

Stellar Mass

1.000 M☉

Metallicity [Fe/H]

0.09

Extended Stellar Properties

Surface gravity (log g)

4.530 dex

Stellar density

1.517 g/cm³

Systemic radial velocity

21.72 km/s

Rotational v·sin i

4.00 km/s

Metallicity ratio

[Fe/H]

Distance

50.35 parsec

Light-years 164.22 ly

V-band magnitude

8.35 mag

Voyager-speed travel 2,896,029 yr

Multi-band Host Photometry — 11 bands

Astrometric Data

Parallax

19.834 mas

Total Proper Motion

197.669 mas/yr

PM Right Ascension

190.25 mas/yr

PM Declination

-53.65 mas/yr

Galactic Cartesian (pc)

x = 0.801 · y = 0.346 · z = 0.489

Equatorial (J2000)

RA 23.33504° · Dec 29.26492°

Galactic ℓ, b

133.799° · -32.721°

Ecliptic λ, β

32.557° · 18.123°

HTM-20 index

-1079815053