Mini-Neptune · GJ 876

GJ 876 d

ExoplanetsDiscovered 2005

Scientific overview

GJ 876 d is a mini-neptune orbiting GJ 876, completing an orbit every 1.9378 days, about 15 light-years from Earth. It was discovered in 2005 using the radial velocity method.

Host star

GJ 876

Spectral type

M2.5V

Temperature

3,294 K

Mass

0.32 M☉

Planetary system — GJ 876 system

View the GJ 876 system (4 known planets).

Planet	Class	Radius (R⊕)	Period (d)	Distance (ly)
GJ 876 dRadial Velocity · 2005	Mini-Neptune	2.51	1.9378	15
GJ 876 cRadial Velocity · 2000	Gas giant	14	30.0881	15
GJ 876 bRadial Velocity · 1998	Gas giant	13.3	61.1166	15
GJ 876 eRadial Velocity · 2010	Mini-Neptune	3.92	124	15

Discovery and detection

Detection method

Radial Velocity Method

Discovery year

2005

Discovered at

W. M. Keck Observatory

Knowledge connections

OrbitsGJ 876
Member of systemGJ 876 system
Discovered by methodRadial Velocity Method
Discovered atW. M. Keck Observatory
Catalogued inNASA Exoplanet Archive

Quick facts

Class: Mini-Neptune
Host star: GJ 876
Discovery method: Radial Velocity Method
Discovery year: 2005
Orbital period: 1.9378 d
Semi-major axis: 0.0208 AU
Eccentricity: 0.207
Radius: 2.51 R⊕
Mass: 6.83 M⊕
Density: 2.38 g/cm³ · derived
Equilibrium temp.: 603 K
Insolation: 28.64 S⊕
Distance: 15 ly

Density is derived from the archive mass and radius via ρ = M / (4⁄3·π·r³); all other values are catalogued measurements.

Derived values

Computed from source-backed inputs via standard formulae — not observations. Every input and constant is traced below.

Bulk density2.38 g/cm³derived
Formula & inputs
Formula: ρ = M / (4⁄3·π·r³) (v1.0.0, impl v1.0.0)
Inputs:
- massEarth = 6.83 M⊕ · NASA
- radiusEarth = 2.51 R⊕ · NASA
Assumptions: M⊕ = 5.972e+24 kg, R⊕ = 6371000 m (IAU 2015 B3 nominal); Assumes a uniform sphere.
Limitations: Withheld above 30 g/cm³ (inconsistent mass/radius inputs).; Archive mass/radius carry no propagated uncertainty here.
Uncertainty: not propagated (inputs carry no catalogued uncertainty)
Computed as of 2026-06-29.

Quality & authority

Partial

Unreviewed

Description: Complete
Source coverage: Partial
Relationship coverage: Complete
Review coverage: None
Citation coverage: None
Image coverage: Not applicable

Data from the NASA Exoplanet Archive. See source quality.