Key parameters at a glance

A radius of 13.20 Earth radii
A mass of 810.46 Earth masses
Surface gravity around 4.65 g
An orbital period of 422.820 days
Semi-major axis 1.2025 AU
Distance from Earth 254.57 light-years
Earth Similarity Index 0.386
Travel time at Voyager 1 speed 4,489,278 years

1 sibling around HD 75898

HD 75898 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 75898 b this	Gas Giant	13.20	810.46	422.820	—	2007
HD 75898 c	Gas Giant	12.60	2,698.36	6,717.000	—	2024

HD 75898 b Planet Profile

Physical Specs

Radius

13.20 R⊕

Radius (Jupiter)

1.180 R♃

Mass

810.46 M⊕

Mass (Jupiter)

2.550 M♃

Density

1.94 g/cm³

Surface Gravity

4.65 g (Earth)

Classification

Planet Type

Gas Giant

ESI Score 0.386

HZ Position Unknown

Controversial No

Discovery

Year 2007

Method Radial Velocity

Facility W. M. Keck Observatory

Telescope 10 m Keck I Telescope

Size rank in cohort

Rank by radius

#847of 1771

top 47.8%

This planet

13.20R⊕

Gas Giant median

13.52R⊕

Nearest-size peers

HD 12661 c 13.20 R⊕ HD 37605 b 13.20 R⊕ MOA-2009-BLG-387L b 13.20 R⊕

Metric	Earth	HD 75898 b	Jupiter
Radius (R⊕)	1.00	13.20	11.21
Mass (M⊕)	1.00	810.46	317.83
Density (g/cm³)	5.51	1.94	1.33
Surface Gravity (g)	1.00	4.65	2.53
Insolation (S⊕)	1.00	—	0.037

Alternative Mass Estimates

Method	Value	Interpretation
Minimum mass (M sin i)	810.462 M⊕	Lower bound from radial-velocity fitting.

Star Catalogue Identifiers

HD 75898

HIP

HIP 43674

TIC

TIC 302580456

Gaia DR2

Gaia DR2 713135102814342656

Gaia DR3

Gaia DR3 713135102814770432

System

HD 75898

Percentile among Gas Giant cohort

Radius 13.200 R⊕ · percentile 49 / cohort 1771

Mass 810.462 M⊕ · percentile 62 / cohort 1747

Orbital period 422.82 d · percentile 65 / cohort 1533

Distance 78.05 pc · percentile 30 / cohort 1759

ESI 0.386 · percentile 81 / cohort 1771

Orbit & Habitability

Orbital Dynamics

Period

422.820 days

Semi-major axis

1.2025 AU

Eccentricity

0.105

Inclination

— °

Year Length

A year here lasts about 1.16 Earth years on a mildly elliptical path at a mean orbital distance of 1.2025 AU.

Extended Orbital Architecture

RV semi-amplitude (K)

58.400 m/s

Transit mid-time (BJD)

2,453,303.0000

Long. of periastron (ω)

-116.80°

Angular separation (arcsec)

15.40000

Eq. Temperature

—

Insolation (S⊕)

—

Earth = 1.00

Earth Similarity (ESI)

0.386

0 = alien, 1 = Earth-identical

Discovery Paper

Primary reference

Robinson et al. 2007

Instrument

HIRES Spectrometer

Publication

2007-12

Observation locale

Ground

Discovery cohort

Planets confirmed in 2007 at W. M. Keck Observatory (7 shown).

HD 11506 b · Gas Giant HD 125612 b · Gas Giant GJ 317 b · Gas Giant HD 5319 b · Gas Giant HD 231701 b · Gas Giant HD 170469 b · Gas Giant HD 175541 b · Gas Giant

Host System: HD 75898

Spectral Class

F-type yellow-white

Effective Temperature

6,122 K — hotter than the Sun (5,778 K)

Estimated Age

3.20 Gyr — younger than the Sun (4.6 Gyr)

Stellar Radius

1.550 R☉

Stellar Mass

1.295 M☉

Metallicity [Fe/H]

0.29

Extended Stellar Properties

Surface gravity (log g)

4.340 dex

Stellar density

0.339 g/cm³

Systemic radial velocity

21.79 km/s

Rotational v·sin i

4.20 km/s

Activity index (log R'HK)

-5.010

Metallicity ratio

[Fe/H]

Distance

78.05 parsec

Light-years 254.57 ly

V-band magnitude

8.03 mag

Voyager-speed travel 4,489,278 yr

Multi-band Host Photometry — 11 bands

Astrometric Data

Parallax

12.784 mas

Total Proper Motion

99.353 mas/yr

PM Right Ascension

-95.13 mas/yr

PM Declination

-28.67 mas/yr

Galactic Cartesian (pc)

x = -0.577 · y = 0.608 · z = 0.545

Equatorial (J2000)

RA 133.46120° · Dec 33.05669°

Galactic ℓ, b

190.970° · 38.936°

Ecliptic λ, β

126.637° · 14.979°

HTM-20 index

-1721451109

Observation Record

Photometric series

RV measurements

Stellar spectra