GJ 3082 b

Astrophysical Synthesis & Habitability Characterization

GJ 3082 b is a confirmed sub-neptune exoplanet orbiting the star GJ 3082, located approximately 54.2 light-years (16.62 parsecs) from the Solar System. First announced in 2020 by Multiple Facilities using the Radial Velocity detection technique (measuring periodic Doppler reflex motion in the host star's spectrum), this world measures 2.79 Earth radii and has a measured mass of 8.2 Earth masses. Combining its mass and radius yields a mean bulk density of 2.08 g/cm³ (an intermediate density indicative of a deep water-ice mantle or dense volatile envelope), a surface gravity of 1.05 g⊕ (10.3 m/s²), and an escape velocity of 19.2 km/s.

In its orbital architecture around GJ 3082, GJ 3082 b completes one full revolution every 11.949 Earth days at a semi-major axis of 0.079 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 71.9 km/s (compared to Earth's 29.8 km/s). Its moderate orbital eccentricity of e = 0.22 carries the world between 0.0616 AU at periapsis and 0.0964 AU at apoapsis, driving measurable seasonal insolation cycles.

⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 458 K (+185°C / +365°F) and receiving 5.52 S⊕ (~7,514 W/m²), GJ 3082 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.

The host star GJ 3082 is classified as a low-mass red dwarf of spectral type M4 with an effective photospheric temperature of 3,910 K, a radius of 0.4652 R☉, a mass of 0.47 M☉, an estimated bolometric luminosity of 0.045 L☉. From Earth, GJ 3082 shines at apparent V-band magnitude 11.041 (faint and requiring research-grade or CCD telescopic photometry) in the Southern celestial hemisphere.

Discovery Facility: Multiple Facilities · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).