Key parameters at a glance

A radius of 12.40 Earth radii
A mass of 3,941.09 Earth masses
Surface gravity around 25.63 g
An orbital period of 13.481 days
Semi-major axis 0.1170 AU
Distance from Earth 240.00 light-years
Earth Similarity Index 0.354
Travel time at Voyager 1 speed 4,232,348 years

HD 87646 b Planet Profile

Physical Specs

Radius

12.40 R⊕

Radius (Jupiter)

1.100 R♃

Mass

3,941.09 M⊕

Mass (Jupiter)

12.400 M♃

Density

11.40 g/cm³

Surface Gravity

25.63 g (Earth)

Classification

Planet Type

Gas Giant

ESI Score 0.354

HZ Position Unknown

Controversial No

Discovery

Year 2016

Method Radial Velocity

Facility Apache Point Observatory

Telescope 2.5m Sloan Digital Sky Survey (SDSS) Telescope

Size rank in cohort

Rank by radius

#1298of 1771

top 73.2%

This planet

12.40R⊕

Gas Giant median

13.52R⊕

Nearest-size peers

HD 110014 b 12.40 R⊕ CFBDSIR J145829+101343 b 12.40 R⊕ MOA-2010-BLG-073L b 12.40 R⊕

Metric	Earth	HD 87646 b	Jupiter
Radius (R⊕)	1.00	12.40	11.21
Mass (M⊕)	1.00	3,941.09	317.83
Density (g/cm³)	5.51	11.40	1.33
Surface Gravity (g)	1.00	25.63	2.53
Insolation (S⊕)	1.00	—	0.037

Alternative Mass Estimates

Method	Value	Interpretation
Minimum mass (M sin i)	3,941.092 M⊕	Lower bound from radial-velocity fitting.

Star Catalogue Identifiers

HD 87646

HIP

HIP 49522 A

TIC

TIC 27064335

Gaia DR2

Gaia DR2 623313901995781632

Gaia DR3

Gaia DR3 623313901995781632

System

HD 87646

Percentile among Gas Giant cohort

Radius 12.400 R⊕ · percentile 25 / cohort 1771

Mass 3,941.092 M⊕ · percentile 91 / cohort 1747

Orbital period 13.48 d · percentile 46 / cohort 1533

Distance 73.58 pc · percentile 29 / cohort 1759

ESI 0.354 · percentile 72 / cohort 1771

Orbit & Habitability

Orbital Dynamics

Period

13.481 days

Semi-major axis

0.1170 AU

Eccentricity

0.050

Inclination

— °

Year Length

A year here lasts approximately 13.48 Earth days (3.7% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.1170 AU.

Eq. Temperature

—

Insolation (S⊕)

—

Earth = 1.00

Earth Similarity (ESI)

0.354

0 = alien, 1 = Earth-identical

Discovery Paper

Primary reference

Ma et al. 2016

Instrument

KeckET

Publication

2016-11

Observation locale

Ground

Host System: HD 87646

Spectral Class

G-type yellow (Sun-like)

Effective Temperature

5,770 K — cooler than the Sun (5,778 K)

Estimated Age

—

Stellar Radius

1.550 R☉

Stellar Mass

1.120 M☉

Metallicity [Fe/H]

-0.17

Extended Stellar Properties

Surface gravity (log g)

4.100 dex

Systemic radial velocity

20.88 km/s

Rotational v·sin i

7.50 km/s

Metallicity ratio

[Fe/H]

Distance

73.58 parsec

Light-years 240.00 ly

V-band magnitude

8.07 mag

Voyager-speed travel 4,232,348 yr

Multi-band Host Photometry — 11 bands

Astrometric Data

Parallax

13.590 mas

Total Proper Motion

78.054 mas/yr

PM Right Ascension

-72.87 mas/yr

PM Declination

-27.97 mas/yr

Galactic Cartesian (pc)

x = -0.838 · y = 0.452 · z = 0.307

Equatorial (J2000)

RA 151.66954° · Dec 17.89498°

Galactic ℓ, b

217.772° · 51.028°

Ecliptic λ, β

147.354° · 5.871°

HTM-20 index

1403503929