Key parameters at a glance

A radius of 1.75 Earth radii
A mass of 8.83 Earth masses
Surface gravity around 2.90 g
An orbital period of 1.008 days
Semi-major axis 0.0201 AU
Equilibrium temperature 2,128 K (1855 °C)
Distance from Earth 156.84 light-years
Earth Similarity Index 0.110
Travel time at Voyager 1 speed 2,765,924 years

1 sibling around HD 213885

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

HD 213885 b Planet Profile

Physical Specs

Radius

1.75 R⊕

Radius (Jupiter)

0.156 R♃

Mass

8.83 M⊕

Mass (Jupiter)

0.028 M♃

Density

9.15 g/cm³

Surface Gravity

2.90 g (Earth)

Classification

Planet Type

Super-Earth

ESI Score 0.110

HZ Position Inner

Controversial No

Discovery

Year 2019

Method Transit

Facility Transiting Exoplanet Survey Satellite (TESS)

Telescope 0.1 m TESS Telescope

Size rank in cohort

Rank by radius

#343of 1176

top 29.1%

This planet

1.75R⊕

Super-Earth median

1.60R⊕

Nearest-size peers

Kepler-1067 c 1.75 R⊕ TOI-1266 d 1.74 R⊕ Kepler-33 b 1.74 R⊕

Metric	Earth	HD 213885 b	Jupiter
Radius (R⊕)	1.00	1.75	11.21
Mass (M⊕)	1.00	8.83	317.83
Density (g/cm³)	5.51	9.15	1.33
Surface Gravity (g)	1.00	2.90	2.53
Insolation (S⊕)	1.00	1,882.94	0.037

Alternative Mass Estimates

Method	Value	Interpretation
Best measured mass	8.830 M⊕	Direct mass measurement (not derived).

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 Super-Earth cohort

Radius 1.745 R⊕ · percentile 71 / cohort 1176

Mass 8.830 M⊕ · percentile 96 / cohort 1176

Orbital period 1.01 d · percentile 5 / cohort 1164

Distance 48.09 pc · percentile 11 / cohort 1171

ESI 0.110 · percentile 1 / cohort 1176

Orbit & Habitability

Orbital Dynamics

Period

1.008 days

Semi-major axis

0.0201 AU

Eccentricity

0.000

Inclination

80.09 °

Year Length

A year here lasts approximately 1.01 Earth days (0.3% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.0201 AU.

Transit Fingerprint

Depth

0.020 %

Duration

1.410 h

Impact parameter b

0.675

Rp / R★

0.014530

Transit midpoint (BJD)

2,458,379.9704

Photometric dip

Transit produces a flux drop of 200 ppm lasting ≈ 1.41 h.

Extended Orbital Architecture

Planet / star radius ratio

0.014530

Semi-major axis / stellar radius

3.927

Impact parameter (b)

0.675

RV semi-amplitude (K)

5.300 m/s

Transit mid-time (BJD)

2,458,379.9704

Angular separation (arcsec)

0.41800

Eq. Temperature

2,128K

(1855 °C)

Insolation (S⊕)

1,882.94

Earth = 1.00

Earth Similarity (ESI)

0.110

0 = alien, 1 = Earth-identical

Inside the inner HZ boundary (too hot for liquid water) — the dayside is scorched.

Detection Signatures

Transit photometry

A transit dip has been observed from at least one telescope.

Radial velocity

Stellar wobble has been measured spectroscopically.

Discovery Paper

Primary reference

Espinoza et al. 2020

Instrument

TESS CCD Array

Publication

2020-01

Observation locale

Space

Discovery cohort

Planets confirmed in 2019 at Transiting Exoplanet Survey Satellite (TESS) (12 shown).

LP 791-18 c · Sub-Neptune LTT 1445 A b · Super-Earth TOI-270 d · Sub-Neptune L 98-59 d · Super-Earth GJ 357 b · Rocky Terrestrial GJ 143 b · Sub-Neptune HD 23472 c · Super-Earth L 98-59 c · Super-Earth LP 791-18 b · Rocky Terrestrial TOI-270 c · Sub-Neptune HD 23472 b · Sub-Neptune TOI-270 b · Super-Earth

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