Key parameters at a glance

A radius of 12.90 Earth radii
A mass of 1,420.69 Earth masses
Surface gravity around 8.54 g
An orbital period of 1,365.000 days
Semi-major axis 2.2940 AU
Distance from Earth 101.09 light-years
Earth Similarity Index 0.424
Travel time at Voyager 1 speed 1,782,695 years

HD 29021 b Planet Profile

Physical Specs

Radius

12.90 R⊕

Radius (Jupiter)

1.150 R♃

Mass

1,420.69 M⊕

Mass (Jupiter)

4.470 M♃

Density

3.64 g/cm³

Surface Gravity

8.54 g (Earth)

Classification

Planet Type

Gas Giant

ESI Score 0.424

HZ Position Unknown

Controversial No

Discovery

Year 2017

Method Radial Velocity

Facility Haute-Provence Observatory

Telescope 1.93 m Telescope

Size rank in cohort

Rank by radius

#1011of 1771

top 57.0%

This planet

12.90R⊕

Gas Giant median

13.52R⊕

Nearest-size peers

HD 55696 b 12.90 R⊕ HD 24040 b 12.90 R⊕ BD-210397 c 12.90 R⊕

Metric	Earth	HD 29021 b	Jupiter
Radius (R⊕)	1.00	12.90	11.21
Mass (M⊕)	1.00	1,420.69	317.83
Density (g/cm³)	5.51	3.64	1.33
Surface Gravity (g)	1.00	8.54	2.53
Insolation (S⊕)	1.00	—	0.037

Alternative Mass Estimates

Method	Value	Interpretation
Best measured mass	1,420.693 M⊕	Direct mass measurement (not derived).
Minimum mass (M sin i)	789.168 M⊕	Lower bound from radial-velocity fitting.

Star Catalogue Identifiers

HD 29021

HIP

HIP 21571

TIC

TIC 458350670

Gaia DR2

Gaia DR2 471536354830504448

Gaia DR3

Gaia DR3 471536354830504448

System

HD 29021

Percentile among Gas Giant cohort

Radius 12.900 R⊕ · percentile 41 / cohort 1771

Mass 1,420.693 M⊕ · percentile 73 / cohort 1747

Orbital period 1,365.00 d · percentile 81 / cohort 1533

Distance 30.99 pc · percentile 8 / cohort 1759

ESI 0.424 · percentile 92 / cohort 1771

Orbit & Habitability

Orbital Dynamics

Period

1,365.000 days

Semi-major axis

2.2940 AU

Eccentricity

0.453

Inclination

33.70 °

Year Length

A year here lasts about 3.74 Earth years on a highly eccentric trajectory at a mean orbital distance of 2.2940 AU.

Eq. Temperature

—

Insolation (S⊕)

—

Earth = 1.00

Earth Similarity (ESI)

0.424

0 = alien, 1 = Earth-identical

Detection Signatures

Radial velocity

Stellar wobble has been measured spectroscopically.

Astrometry

Positional wobble of the host star was measured.

Discovery Paper

Primary reference

Rey et al. 2017

Instrument

ELODIE Spectrograph

Publication

2017-05

Observation locale

Ground

Discovery cohort

Planets confirmed in 2017 at Haute-Provence Observatory (2 shown).

HD 42012 b · Gas Giant HD 17674 b · Gas Giant

Host System: HD 29021

Spectral Class

G-type yellow (Sun-like)

Effective Temperature

5,560 K — cooler than the Sun (5,778 K)

Estimated Age

5.50 Gyr — older than the Sun (4.6 Gyr)

Stellar Radius

0.850 R☉

Stellar Mass

0.860 M☉

Metallicity [Fe/H]

-0.30

Extended Stellar Properties

Surface gravity (log g)

4.440 dex

Stellar density

1.992 g/cm³

Systemic radial velocity

-0.20 km/s

Rotational v·sin i

2.70 km/s

Metallicity ratio

[Fe/H]

Distance

30.99 parsec

Light-years 101.09 ly

V-band magnitude

7.76 mag

Voyager-speed travel 1,782,695 yr

Multi-band Host Photometry — 11 bands

Astrometric Data

Parallax

32.236 mas

Total Proper Motion

66.540 mas/yr

PM Right Ascension

62.43 mas/yr

PM Declination

23.01 mas/yr

Galactic Cartesian (pc)

x = 0.172 · y = 0.459 · z = 0.872

Equatorial (J2000)

RA 69.46814° · Dec 60.67630°

Galactic ℓ, b

147.393° · 9.072°

Ecliptic λ, β

77.383° · 38.133°

HTM-20 index

-46841877