Key parameters at a glance

A radius of 13.50 Earth radii
A mass of 532.36 Earth masses
Surface gravity around 2.92 g
An orbital period of 51.636 days
Semi-major axis 0.2800 AU
Distance from Earth 187.88 light-years
Earth Similarity Index 0.351
Travel time at Voyager 1 speed 3,313,187 years

1 sibling around HD 74156

HD 74156 b 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 74156 b this	Gas Giant	13.50	532.36	51.636	—	2003
HD 74156 c	Gas Giant	12.50	2,753.98	2,448.487	—	2003

HD 74156 b Planet Profile

Physical Specs

Radius

13.50 R⊕

Radius (Jupiter)

1.200 R♃

Mass

532.36 M⊕

Mass (Jupiter)

1.675 M♃

Density

1.19 g/cm³

Surface Gravity

2.92 g (Earth)

Classification

Planet Type

Gas Giant

ESI Score 0.351

HZ Position Unknown

Controversial No

Discovery

Year 2003

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 74156 b	Jupiter
Radius (R⊕)	1.00	13.50	11.21
Mass (M⊕)	1.00	532.36	317.83
Density (g/cm³)	5.51	1.19	1.33
Surface Gravity (g)	1.00	2.92	2.53
Insolation (S⊕)	1.00	—	0.037

Alternative Mass Estimates

Method	Value	Interpretation
Minimum mass (M sin i)	532.363 M⊕	Lower bound from radial-velocity fitting.

Star Catalogue Identifiers

HD 74156

HIP

HIP 42723

TIC

TIC 379949822

Gaia DR2

Gaia DR2 582221750852254080

Gaia DR3

Gaia DR3 582221750852254080

System

HD 74156

Percentile among Gas Giant cohort

Radius 13.500 R⊕ · percentile 59 / cohort 1771

Mass 532.363 M⊕ · percentile 50 / cohort 1747

Orbital period 51.64 d · percentile 51 / cohort 1533

Distance 57.60 pc · percentile 24 / cohort 1759

ESI 0.351 · percentile 71 / cohort 1771

Orbit & Habitability

Orbital Dynamics

Period

51.636 days

Semi-major axis

0.2800 AU

Eccentricity

0.636

Inclination

— °

Year Length

A year here lasts approximately 51.64 Earth days (14.1% of a terrestrial year) on a highly eccentric trajectory at a mean orbital distance of 0.2800 AU.

Extended Orbital Architecture

RV semi-amplitude (K)

110.985 m/s

Transit mid-time (BJD)

2,455,231.4640

Long. of periastron (ω)

174.40°

Angular separation (arcsec)

4.86000

Eq. Temperature

—

Insolation (S⊕)

—

Earth = 1.00

Earth Similarity (ESI)

0.351

0 = alien, 1 = Earth-identical

Discovery Paper

Primary reference

Naef et al. 2004

Instrument

ELODIE Spectrograph

Publication

2004-01

Observation locale

Ground

Discovery cohort

Planets confirmed in 2003 at Haute-Provence Observatory (3 shown).

HD 74156 c · Gas Giant HD 23596 b · Gas Giant HD 190360 b · Gas Giant

Host System: HD 74156

Spectral Class

G-type yellow (Sun-like)

Effective Temperature

6,068 K — hotter than the Sun (5,778 K)

Estimated Age

3.70 Gyr — younger than the Sun (4.6 Gyr)

Stellar Radius

1.511 R☉

Stellar Mass

1.100 M☉

Metallicity [Fe/H]

0.13

Extended Stellar Properties

Surface gravity (log g)

4.139 dex

Stellar density

0.479 g/cm³

Systemic radial velocity

3.84 km/s

Rotational v·sin i

4.06 km/s

Activity index (log R'HK)

-5.080

Metallicity ratio

[Fe/H]

Distance

57.60 parsec

Light-years 187.88 ly

V-band magnitude

7.61 mag

Voyager-speed travel 3,313,187 yr

Multi-band Host Photometry — 11 bands

Astrometric Data

Parallax

17.332 mas

Total Proper Motion

201.783 mas/yr

PM Right Ascension

24.47 mas/yr

PM Declination

-200.29 mas/yr

Galactic Cartesian (pc)

x = -0.649 · y = 0.757 · z = 0.080

Equatorial (J2000)

RA 130.60478° · Dec 4.57723°

Galactic ℓ, b

221.986° · 26.705°

Ecliptic λ, β

131.777° · -13.169°

HTM-20 index

2025332893

Observation Record

Photometric series

RV measurements

Stellar spectra

Archive notes