Key parameters at a glance

A radius of 12.80 Earth radii
A mass of 1,808.44 Earth masses
Surface gravity around 11.04 g
An orbital period of 252.060 days
Semi-major axis 1.0500 AU
Distance from Earth 412.54 light-years
Earth Similarity Index 0.436
Travel time at Voyager 1 speed 7,275,057 years

HD 102888 b Planet Profile

Physical Specs

Radius

12.80 R⊕

Radius (Jupiter)

1.140 R♃

Mass

1,808.44 M⊕

Mass (Jupiter)

5.690 M♃

Density

4.74 g/cm³

Surface Gravity

11.04 g (Earth)

Classification

Planet Type

Gas Giant

ESI Score 0.436

HZ Position Unknown

Controversial No

Discovery

Year 2025

Method Radial Velocity

Facility La Silla Observatory

Telescope 1.2 m Leonhard Euler Telescope

Size rank in cohort

Rank by radius

#1063of 1771

top 60.0%

This planet

12.80R⊕

Gas Giant median

13.52R⊕

Nearest-size peers

HD 240210 b 12.80 R⊕ HD 29985 b 12.80 R⊕ HD 148164 c 12.80 R⊕

Metric	Earth	HD 102888 b	Jupiter
Radius (R⊕)	1.00	12.80	11.21
Mass (M⊕)	1.00	1,808.44	317.83
Density (g/cm³)	5.51	4.74	1.33
Surface Gravity (g)	1.00	11.04	2.53
Insolation (S⊕)	1.00	—	0.037

Alternative Mass Estimates

Method	Value	Interpretation
Minimum mass (M sin i)	1,808.444 M⊕	Lower bound from radial-velocity fitting.

Star Catalogue Identifiers

HD 102888

HIP

HIP 57749

TIC

TIC 397394991

Gaia DR2

Gaia DR2 3487277912642549248

Gaia DR3

Gaia DR3 3487277912642549248

System

HD 102888

Percentile among Gas Giant cohort

Radius 12.800 R⊕ · percentile 37 / cohort 1771

Mass 1,808.444 M⊕ · percentile 78 / cohort 1747

Orbital period 252.06 d · percentile 59 / cohort 1533

Distance 126.48 pc · percentile 40 / cohort 1759

ESI 0.436 · percentile 96 / cohort 1771

Orbit & Habitability

Orbital Dynamics

Period

252.060 days

Semi-major axis

1.0500 AU

Eccentricity

0.110

Inclination

— °

Year Length

A year here lasts approximately 252.06 Earth days (69.0% of a terrestrial year) on a mildly elliptical path at a mean orbital distance of 1.0500 AU.

Eq. Temperature

—

Insolation (S⊕)

—

Earth = 1.00

Earth Similarity (ESI)

0.436

0 = alien, 1 = Earth-identical

Discovery Paper

Primary reference

Fontanet et al. 2025

Instrument

CORALIE Spectrograph

Publication

2025-05

Observation locale

Ground

Discovery cohort

Planets confirmed in 2025 at La Silla Observatory (12 shown).

Proxima Cen d · Rocky Terrestrial TOI-1203 c · Sub-Neptune HD 23079 c · Sub-Neptune HD 196067 c · Sub-Neptune HD 87816 b · Gas Giant HD 94890 c · Gas Giant TOI-756 c · Gas Giant TOI-1203 e · Neptune-like HD 94890 b · Gas Giant HD 87816 c · Gas Giant GJ 2126 b · Gas Giant HD 28471 d · Sub-Neptune

Host System: HD 102888

Spectral Class

G-type yellow (Sun-like)

Effective Temperature

4,990 K — cooler than the Sun (5,778 K)

Estimated Age

—

Stellar Radius

8.600 R☉

Stellar Mass

2.420 M☉

Metallicity [Fe/H]

0.07

Distance

126.48 parsec

Light-years 412.54 ly

V-band magnitude

6.48 mag

Voyager-speed travel 7,275,057 yr

Multi-band Host Photometry — 11 bands

Astrometric Data

Parallax

7.878 mas

Total Proper Motion

82.893 mas/yr

PM Right Ascension

-82.62 mas/yr

PM Declination

6.69 mas/yr

Galactic Cartesian (pc)

x = -0.888 · y = 0.036 · z = -0.458

Equatorial (J2000)

RA 177.65453° · Dec -27.27791°

Galactic ℓ, b

286.667° · 33.666°

Ecliptic λ, β

189.516° · -25.783°

HTM-20 index

2111551958