Key parameters at a glance

A radius of 13.50 Earth radii
A mass of 490.09 Earth masses
Surface gravity around 2.69 g
An orbital period of 380.200 days
Semi-major axis 1.1800 AU
Distance from Earth 619.40 light-years
Earth Similarity Index 0.345
Travel time at Voyager 1 speed 10,923,054 years

HD 28678 b Planet Profile

Physical Specs

Radius

13.50 R⊕

Radius (Jupiter)

1.210 R♃

Mass

490.09 M⊕

Mass (Jupiter)

1.542 M♃

Density

1.09 g/cm³

Surface Gravity

2.69 g (Earth)

Classification

Planet Type

Gas Giant

ESI Score 0.345

HZ Position Unknown

Controversial No

Discovery

Year 2011

Method Radial Velocity

Facility W. M. Keck Observatory

Telescope 10 m Keck I 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 28678 b	Jupiter
Radius (R⊕)	1.00	13.50	11.21
Mass (M⊕)	1.00	490.09	317.83
Density (g/cm³)	5.51	1.09	1.33
Surface Gravity (g)	1.00	2.69	2.53
Insolation (S⊕)	1.00	—	0.037

Alternative Mass Estimates

Method	Value	Interpretation
Minimum mass (M sin i)	490.094 M⊕	Lower bound from radial-velocity fitting.

Star Catalogue Identifiers

HD 28678

HIP

HIP 21109

TIC

TIC 449145115

Gaia DR2

Gaia DR2 3282351760091020672

Gaia DR3

Gaia DR3 3282351760091020672

System

HD 28678

Percentile among Gas Giant cohort

Radius 13.500 R⊕ · percentile 59 / cohort 1771

Mass 490.094 M⊕ · percentile 48 / cohort 1747

Orbital period 380.20 d · percentile 63 / cohort 1533

Distance 189.91 pc · percentile 49 / cohort 1759

ESI 0.345 · percentile 69 / cohort 1771

Orbit & Habitability

Orbital Dynamics

Period

380.200 days

Semi-major axis

1.1800 AU

Eccentricity

0.149

Inclination

— °

Year Length

A year here lasts about 1.04 Earth years on a mildly elliptical path at a mean orbital distance of 1.1800 AU.

Eq. Temperature

—

Insolation (S⊕)

—

Earth = 1.00

Earth Similarity (ESI)

0.345

0 = alien, 1 = Earth-identical

Discovery Paper

Primary reference

Johnson et al. 2011

Instrument

HIRES Spectrometer

Publication

2011-12

Observation locale

Ground

Discovery cohort

Planets confirmed in 2011 at W. M. Keck Observatory (12 shown).

HD 5891 b · Gas Giant HD 102329 b · Gas Giant HD 18742 b · Gas Giant HD 142245 b · Gas Giant CFBDSIR J145829+101343 b · Gas Giant HD 1502 b · Gas Giant HD 108863 b · Gas Giant HD 82886 b · Gas Giant HD 106270 b · Gas Giant HD 98219 b · Gas Giant HD 152581 b · Gas Giant HD 131496 b · Gas Giant

Host System: HD 28678

Spectral Class

G-type yellow (Sun-like)

Effective Temperature

4,972 K — cooler than the Sun (5,778 K)

Estimated Age

1.80 Gyr — younger than the Sun (4.6 Gyr)

Stellar Radius

6.480 R☉

Stellar Mass

1.530 M☉

Metallicity [Fe/H]

-0.11

Extended Stellar Properties

Surface gravity (log g)

3.060 dex

Systemic radial velocity

61.77 km/s

Rotational v·sin i

2.97 km/s

Metallicity ratio

[Fe/H]

Distance

189.91 parsec

Light-years 619.40 ly

V-band magnitude

8.38 mag

Voyager-speed travel 10,923,054 yr

Multi-band Host Photometry — 11 bands

Astrometric Data

Parallax

5.238 mas

Total Proper Motion

10.541 mas/yr

PM Right Ascension

1.21 mas/yr

PM Declination

-10.47 mas/yr

Galactic Cartesian (pc)

x = 0.376 · y = 0.923 · z = 0.080

Equatorial (J2000)

RA 67.85606° · Dec 4.57525°

Galactic ℓ, b

190.821° · -28.198°

Ecliptic λ, β

66.848° · -17.102°

HTM-20 index

-1303103038