Key parameters at a glance

A radius of 13.10 Earth radii
A mass of 1,080.62 Earth masses
Surface gravity around 6.30 g
An orbital period of 766.000 days
Semi-major axis 1.8200 AU
Distance from Earth 530.61 light-years
Earth Similarity Index 0.405
Travel time at Voyager 1 speed 9,357,252 years

HD 18742 b Planet Profile

Physical Specs

Radius

13.10 R⊕

Radius (Jupiter)

1.170 R♃

Mass

1,080.62 M⊕

Mass (Jupiter)

3.400 M♃

Density

2.64 g/cm³

Surface Gravity

6.30 g (Earth)

Classification

Planet Type

Gas Giant

ESI Score 0.405

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

#910of 1771

top 51.3%

This planet

13.10R⊕

Gas Giant median

13.52R⊕

Nearest-size peers

GJ 3021 b 13.10 R⊕ HD 221287 b 13.10 R⊕ HD 37605 c 13.10 R⊕

Metric	Earth	HD 18742 b	Jupiter
Radius (R⊕)	1.00	13.10	11.21
Mass (M⊕)	1.00	1,080.62	317.83
Density (g/cm³)	5.51	2.64	1.33
Surface Gravity (g)	1.00	6.30	2.53
Insolation (S⊕)	1.00	—	0.037

Alternative Mass Estimates

Method	Value	Interpretation
Minimum mass (M sin i)	1,080.622 M⊕	Lower bound from radial-velocity fitting.

Star Catalogue Identifiers

HD 18742

HIP

HIP 13993

TIC

TIC 71345433

Gaia DR2

Gaia DR2 5079636934554540160

Gaia DR3

Gaia DR3 5079636934554540160

System

HD 18742

Percentile among Gas Giant cohort

Radius 13.100 R⊕ · percentile 46 / cohort 1771

Mass 1,080.622 M⊕ · percentile 68 / cohort 1747

Orbital period 766.00 d · percentile 73 / cohort 1533

Distance 162.69 pc · percentile 46 / cohort 1759

ESI 0.405 · percentile 87 / cohort 1771

Orbit & Habitability

Orbital Dynamics

Period

766.000 days

Semi-major axis

1.8200 AU

Eccentricity

0.040

Inclination

— °

Year Length

A year here lasts about 2.10 Earth years on a nearly circular orbit at a mean orbital distance of 1.8200 AU.

Eq. Temperature

—

Insolation (S⊕)

—

Earth = 1.00

Earth Similarity (ESI)

0.405

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 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 HD 30856 b · Gas Giant

Host System: HD 18742

Spectral Class

G-type yellow (Sun-like)

Effective Temperature

4,940 K — cooler than the Sun (5,778 K)

Estimated Age

2.30 Gyr — younger than the Sun (4.6 Gyr)

Stellar Radius

5.130 R☉

Stellar Mass

1.360 M☉

Metallicity [Fe/H]

-0.04

Extended Stellar Properties

Surface gravity (log g)

3.090 dex

Systemic radial velocity

-13.49 km/s

Rotational v·sin i

2.98 km/s

Metallicity ratio

[Fe/H]

Distance

162.69 parsec

Light-years 530.61 ly

V-band magnitude

7.81 mag

Voyager-speed travel 9,357,252 yr

Multi-band Host Photometry — 11 bands

Astrometric Data

Parallax

6.121 mas

Total Proper Motion

30.193 mas/yr

PM Right Ascension

-19.72 mas/yr

PM Declination

-22.86 mas/yr

Galactic Cartesian (pc)

x = 0.660 · y = 0.662 · z = -0.355

Equatorial (J2000)

RA 45.04431° · Dec -20.80270°

Galactic ℓ, b

207.805° · -60.005°

Ecliptic λ, β

35.181° · -36.085°

HTM-20 index

-56446310