Key parameters at a glance

A radius of 12.50 Earth radii
A mass of 2,997.76 Earth masses
Surface gravity around 19.19 g
An orbital period of 133.404 days
Semi-major axis 0.5020 AU
Distance from Earth 118.05 light-years
Earth Similarity Index 0.391
Travel time at Voyager 1 speed 2,081,821 years

1 sibling around HD 156279

HD 156279 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 156279 b this	Gas Giant	12.50	2,997.76	133.404	—	2011
HD 156279 c	Gas Giant	12.50	3,098.83	4,818.254	—	2018

HD 156279 b Planet Profile

Physical Specs

Radius

12.50 R⊕

Radius (Jupiter)

1.120 R♃

Mass

2,997.76 M⊕

Mass (Jupiter)

9.432 M♃

Density

8.43 g/cm³

Surface Gravity

19.19 g (Earth)

Classification

Planet Type

Gas Giant

ESI Score 0.391

HZ Position Unknown

Controversial No

Discovery

Year 2011

Method Radial Velocity

Facility Haute-Provence Observatory

Telescope 1.93 m Telescope

Size rank in cohort

Rank by radius

#1235of 1771

top 69.7%

This planet

12.50R⊕

Gas Giant median

13.52R⊕

Nearest-size peers

HD 33283 b 12.50 R⊕ gam1 Leo b 12.50 R⊕ HD 156279 c 12.50 R⊕

Metric	Earth	HD 156279 b	Jupiter
Radius (R⊕)	1.00	12.50	11.21
Mass (M⊕)	1.00	2,997.76	317.83
Density (g/cm³)	5.51	8.43	1.33
Surface Gravity (g)	1.00	19.19	2.53
Insolation (S⊕)	1.00	—	0.037

Alternative Mass Estimates

Method	Value	Interpretation
Minimum mass (M sin i)	2,997.758 M⊕	Lower bound from radial-velocity fitting.

Star Catalogue Identifiers

HD 156279

HIP

HIP 84171

TIC

TIC 232606278

Gaia DR2

Gaia DR2 1631084478574318976

Gaia DR3

Gaia DR3 1631084478574318976

System

HD 156279

Percentile among Gas Giant cohort

Radius 12.500 R⊕ · percentile 28 / cohort 1771

Mass 2,997.758 M⊕ · percentile 86 / cohort 1747

Orbital period 133.40 d · percentile 55 / cohort 1533

Distance 36.19 pc · percentile 11 / cohort 1759

ESI 0.391 · percentile 83 / cohort 1771

Orbit & Habitability

Orbital Dynamics

Period

133.404 days

Semi-major axis

0.5020 AU

Eccentricity

0.647

Inclination

87.00 °

Year Length

A year here lasts approximately 133.40 Earth days (36.5% of a terrestrial year) on a highly eccentric trajectory at a mean orbital distance of 0.5020 AU.

Extended Orbital Architecture

RV semi-amplitude (K)

509.454 m/s

Transit mid-time (BJD)

2,455,464.9400

Long. of periastron (ω)

265.74°

Angular separation (arcsec)

13.90000

Eq. Temperature

—

Insolation (S⊕)

—

Earth = 1.00

Earth Similarity (ESI)

0.391

0 = alien, 1 = Earth-identical

Detection Signatures

Radial velocity

Stellar wobble has been measured spectroscopically.

Astrometry

Positional wobble of the host star was measured.

Discovery Paper

Primary reference

Diaz et al. 2012

Instrument

SOPHIE Spectrograph

Publication

2012-02

Observation locale

Ground

Discovery cohort

Planets confirmed in 2011 at Haute-Provence Observatory (2 shown).

HD 222155 b · Gas Giant HD 22781 b · Gas Giant

Host System: HD 156279

Spectral Class

G-type yellow (Sun-like)

Effective Temperature

5,453 K — cooler than the Sun (5,778 K)

Estimated Age

4.10 Gyr — younger than the Sun (4.6 Gyr)

Stellar Radius

0.950 R☉

Stellar Mass

0.940 M☉

Metallicity [Fe/H]

0.14

Extended Stellar Properties

Surface gravity (log g)

4.460 dex

Stellar density

1.493 g/cm³

Systemic radial velocity

-20.64 km/s

Rotational v·sin i

2.51 km/s

Activity index (log R'HK)

-5.060

Metallicity ratio

[Fe/H]

Distance

36.19 parsec

Light-years 118.05 ly

V-band magnitude

8.07 mag

Voyager-speed travel 2,081,821 yr

Multi-band Host Photometry — 11 bands

Astrometric Data

Parallax

27.600 mas

Total Proper Motion

160.220 mas/yr

PM Right Ascension

-2.03 mas/yr

PM Declination

160.21 mas/yr

Galactic Cartesian (pc)

x = -0.093 · y = -0.439 · z = 0.894

Equatorial (J2000)

RA 258.09667° · Dec 63.35278°

Galactic ℓ, b

93.086° · 35.082°

Ecliptic λ, β

206.985° · 84.041°

HTM-20 index

-1643942942

Observation Record

Photometric series

RV measurements

Stellar spectra