Mini-Neptune · GJ 1214

GJ 1214 b

ExoplanetsDiscovered 2009

Scientific overview

GJ 1214 b is a mini-neptune orbiting GJ 1214, completing an orbit every 1.5804 days, about 48 light-years from Earth. It was discovered in 2009 using the transit method.

Host star

Onkaria

Spectral type

M4 V

Temperature

3,101 K

Mass

0.182 M☉

Discovery and detection

Detection method

Transit Method

Discovery year

2009

Knowledge connections

OrbitsOnkaria
Discovered by methodTransit Method
Catalogued inNASA Exoplanet Archive
Similar toMini-Neptune

Quick facts

Class: Mini-Neptune
Host star: Onkaria
Discovery method: Transit Method
Discovery year: 2009
Orbital period: 1.5804 d
Semi-major axis: 0.0151 AU
Eccentricity: 0.006
Radius: 2.73 R⊕
Mass: 8.41 M⊕
Density: 2.28 g/cm³ · derived
Equilibrium temp.: 567 K
Insolation: 17.2 S⊕
Distance: 48 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 density2.28 g/cm³derived
Formula & inputs
Formula: ρ = M / (4⁄3·π·r³) (v1.0.0, impl v1.0.0)
Inputs:
- massEarth = 8.41 M⊕ · NASA
- radiusEarth = 2.73 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.