Key parameters at a glance

A radius of 5.44 Earth radii
A mass of 25.43 Earth masses
Surface gravity around 0.86 g
An orbital period of 10.022 days
Semi-major axis 0.0910 AU
Distance from Earth 228.58 light-years
Earth Similarity Index 0.452
Travel time at Voyager 1 speed 4,031,047 years

1 sibling around HD 105618

HD 105618 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 105618 b this	Neptune-like	5.44	25.43	10.022	—	2022
HD 105618 c	Gas Giant	11.90	8,419.59	77,114.072	—	2022

HD 105618 b Planet Profile

Physical Specs

Radius

5.44 R⊕

Radius (Jupiter)

0.485 R♃

Mass

25.43 M⊕

Mass (Jupiter)

0.080 M♃

Density

0.87 g/cm³

Surface Gravity

0.86 g (Earth)

Classification

Planet Type

Neptune-like

ESI Score 0.452

HZ Position Unknown

Controversial No

Discovery

Year 2022

Method Radial Velocity

Facility Multiple Observatories

Telescope Multiple Telescopes

Size rank in cohort

Rank by radius

#322of 574

top 55.9%

This planet

5.44R⊕

Neptune-like median

6.39R⊕

Nearest-size peers

HD 190360 c 5.44 R⊕ HD 99492 b 5.44 R⊕ KOI-1783.02 5.44 R⊕

Metric	Earth	HD 105618 b	Jupiter
Radius (R⊕)	1.00	5.44	11.21
Mass (M⊕)	1.00	25.43	317.83
Density (g/cm³)	5.51	0.87	1.33
Surface Gravity (g)	1.00	0.86	2.53
Insolation (S⊕)	1.00	—	0.037

Alternative Mass Estimates

Method	Value	Interpretation
Minimum mass (M sin i)	25.426 M⊕	Lower bound from radial-velocity fitting.

Star Catalogue Identifiers

HD 105618

TIC

TIC 397519199

Gaia DR2

Gaia DR2 3906803888551408000

Gaia DR3

Gaia DR3 3906803888551408000

System

HD 105618

Percentile among Neptune-like cohort

Radius 5.440 R⊕ · percentile 43 / cohort 574

Mass 25.426 M⊕ · percentile 43 / cohort 574

Orbital period 10.02 d · percentile 36 / cohort 524

Distance 70.08 pc · percentile 19 / cohort 572

ESI 0.452 · percentile 81 / cohort 574

Orbit & Habitability

Orbital Dynamics

Period

10.022 days

Semi-major axis

0.0910 AU

Eccentricity

0.455

Inclination

— °

Year Length

A year here lasts approximately 10.02 Earth days (2.7% of a terrestrial year) on a highly eccentric trajectory at a mean orbital distance of 0.0910 AU.

Eq. Temperature

—

Insolation (S⊕)

—

Earth = 1.00

Earth Similarity (ESI)

0.452

0 = alien, 1 = Earth-identical

Discovery Paper

Primary reference

Feng et al. 2022

Instrument

Multiple Instruments

Publication

2022-09

Observation locale

Ground

Discovery cohort

Planets confirmed in 2022 at Multiple Observatories (12 shown).

Kepler-138 e · Rocky Terrestrial HD 93351 b · Super-Earth GJ 1002 b · Rocky Terrestrial GJ 2030 b · Sub-Neptune GJ 3929 c · Sub-Neptune HD 217786 c · Sub-Neptune GJ 1002 c · Rocky Terrestrial HD 155918 b · Sub-Neptune HD 213519 b · Sub-Neptune HD 191939 g · Sub-Neptune GJ 514 b · Sub-Neptune HD 12235 b · Sub-Neptune

Host System: HD 105618

Spectral Class

G-type yellow (Sun-like)

Effective Temperature

5,671 K — cooler than the Sun (5,778 K)

Estimated Age

—

Stellar Radius

1.274 R☉

Stellar Mass

1.010 M☉

Metallicity [Fe/H]

—

Distance

70.08 parsec

Light-years 228.58 ly

V-band magnitude

8.63 mag

Voyager-speed travel 4,031,047 yr

Multi-band Host Photometry — 11 bands

Astrometric Data

Parallax

14.240 mas

Total Proper Motion

104.631 mas/yr

PM Right Ascension

-104.61 mas/yr

PM Declination

-1.96 mas/yr

Galactic Cartesian (pc)

x = -0.980 · y = -0.041 · z = 0.194

Equatorial (J2000)

RA 182.40213° · Dec 11.21157°

Galactic ℓ, b

269.217° · 71.291°

Ecliptic λ, β

177.681° · 11.230°

HTM-20 index

569010175