Key parameters at a glance

A radius of 4.71 Earth radii
A mass of 19.95 Earth masses
Surface gravity around 0.90 g
An orbital period of 4.785 days
Semi-major axis 0.0568 AU
Equilibrium temperature 1,265 K (992 °C)
Distance from Earth 156.84 light-years
Earth Similarity Index 0.148
Travel time at Voyager 1 speed 2,765,924 years

1 sibling around HD 213885

HD 213885 c 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 213885 b	Super-Earth	1.75	8.83	1.008	2,128	2019
HD 213885 c this	Neptune-like	4.71	19.95	4.785	1,265	2019

HD 213885 c Planet Profile

Physical Specs

Radius

4.71 R⊕

Radius (Jupiter)

0.420 R♃

Mass

19.95 M⊕

Mass (Jupiter)

0.063 M♃

Density

1.05 g/cm³

Surface Gravity

0.90 g (Earth)

Classification

Planet Type

Neptune-like

ESI Score 0.148

HZ Position Unknown

Controversial No

Discovery

Year 2019

Method Radial Velocity

Facility Multiple Observatories

Telescope Multiple Telescopes

Size rank in cohort

Rank by radius

#429of 574

top 74.6%

This planet

4.71R⊕

Neptune-like median

6.39R⊕

Nearest-size peers

Kepler-20 g 4.71 R⊕ Kepler-318 b 4.71 R⊕ LP 714-47 b 4.70 R⊕

Metric	Earth	HD 213885 c	Jupiter
Radius (R⊕)	1.00	4.71	11.21
Mass (M⊕)	1.00	19.95	317.83
Density (g/cm³)	5.51	1.05	1.33
Surface Gravity (g)	1.00	0.90	2.53
Insolation (S⊕)	1.00	—	0.037

Alternative Mass Estimates

Method	Value	Interpretation
Minimum mass (M sin i)	19.950 M⊕	Lower bound from radial-velocity fitting.

Star Catalogue Identifiers

HD 213885

HIP

HIP 111553

TIC

TIC 403224672

Gaia DR2

Gaia DR2 6407428994690988928

Gaia DR3

Gaia DR3 6407428994690988928

System

HD 213885

Percentile among Neptune-like cohort

Radius 4.710 R⊕ · percentile 25 / cohort 574

Mass 19.950 M⊕ · percentile 28 / cohort 574

Orbital period 4.79 d · percentile 19 / cohort 524

Distance 48.09 pc · percentile 15 / cohort 572

ESI 0.148 · percentile 13 / cohort 574

Orbit & Habitability

Orbital Dynamics

Period

4.785 days

Semi-major axis

0.0568 AU

Eccentricity

0.000

Inclination

— °

Year Length

A year here lasts approximately 4.79 Earth days (1.3% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.0568 AU.

Eq. Temperature

1,265K

(992 °C)

Insolation (S⊕)

—

Earth = 1.00

Earth Similarity (ESI)

0.148

0 = alien, 1 = Earth-identical

Insufficient insolation data — the dayside is scorched.

Discovery Paper

Primary reference

Espinoza et al. 2020

Instrument

Multiple Instruments

Publication

2020-01

Observation locale

Ground

Discovery cohort

Planets confirmed in 2019 at Multiple Observatories (8 shown).

Gl 49 b · Sub-Neptune GJ 357 c · Super-Earth GJ 357 d · Sub-Neptune HR 5183 b · Gas Giant NSVS 14256825 b · Gas Giant 7 CMa c · Gas Giant USco1556 b · Gas Giant USco1621 b · Gas Giant

Host System: HD 213885

Spectral Class

G-type yellow (Sun-like)

Effective Temperature

5,978 K — hotter than the Sun (5,778 K)

Estimated Age

3.80 Gyr — younger than the Sun (4.6 Gyr)

Stellar Radius

1.101 R☉

Stellar Mass

1.068 M☉

Metallicity [Fe/H]

-0.04

Extended Stellar Properties

Surface gravity (log g)

4.383 dex

Stellar density

1.127 g/cm³

Systemic radial velocity

36.22 km/s

Rotational v·sin i

3.00 km/s

Rotation period

18.58 days

Activity index (log R'HK)

-4.900

Metallicity ratio

[Fe/H]

Distance

48.09 parsec

Light-years 156.84 ly

V-band magnitude

7.95 mag

Voyager-speed travel 2,765,924 yr

Multi-band Host Photometry — 14 bands

Astrometric Data

Parallax

20.766 mas

Total Proper Motion

137.384 mas/yr

PM Right Ascension

-108.39 mas/yr

PM Declination

-84.42 mas/yr

Galactic Cartesian (pc)

x = 0.469 · y = -0.180 · z = -0.865

Equatorial (J2000)

RA 338.98372° · Dec -59.86483°

Galactic ℓ, b

328.702° · -49.935°

Ecliptic λ, β

312.621° · -46.208°

HTM-20 index

-121636437