GJ 900 b
Astrophysical Synthesis & Habitability Characterization
GJ 900 b is a confirmed gas giant exoplanet orbiting the star GJ 900 A, located approximately 67.9 light-years (20.81 parsecs) from the Solar System. First announced in 2024 by Multiple Observatories using the Imaging detection technique (resolved directly via high-contrast coronagraphic or interferometric imaging), this world measures 12.4 Earth radii (1.11 Jupiter radii) and has a measured mass of 3496.112 Earth masses (11 Jupiter masses). Combining its mass and radius yields a mean bulk density of 10.11 g/cm³ (an iron-enriched, high-compression rocky core), a surface gravity of 22.74 g⊕ (223 m/s²), and an escape velocity of 187.8 km/s.
❄️ Thermal Regime (Cryogenic Zone): With an equilibrium temperature of 1 K (-272°C / -458°F), surface water and volatile species on GJ 900 b would remain locked in cryogenic ice phases unless warmed by subsurface tidal or radiogenic heating.
The host star GJ 900 A is classified as an orange K-type star of spectral type K7 with an effective photospheric temperature of 3,976 K, a radius of 0.7162 R☉, a mass of 1.08 M☉, an estimated bolometric luminosity of 0.115 L☉. Stellar evolution modeling indicates an estimated stellar age of 0.2 Gyr and a metallicity of [Fe/H] = -0.63 dex (metal-poor relative to the Sun). From Earth, GJ 900 A shines at apparent V-band magnitude 9.59 (accessible to binoculars and small amateur telescopes) in the Northern celestial hemisphere.
Methodology: Computed using the Schulze-Makuch et al. (2011) weighted metric comparing physical interior (radius, estimated density) and surface thermal regime (escape velocity, equilibrium temperature).
Discovery Facility: Multiple Observatories · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | GJ 900 A |
| Spectral Type | K7 |
| Effective Temp (Teff) | 3,976 K |
| Stellar Radius | 0.7162 R☉ |
| Stellar Mass | 1.0800 M☉ |
| Bolometric Luminosity | 0.115 L☉ |
| Metallicity [Fe/H] | -0.630 dex |
| Stellar Age | 0.200 Gyr |
| Apparent Magnitude | V: 9.590 · G: 9.026 |
| System Architecture | 3 Stars, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 12000.000000 AU |
| Orbital Period | — |
| Orbital Eccentricity (e) | Circular (0.00) |
| Orbital Inclination (i) | — |
| Mean Bulk Density | 10.11 g/cm³ (187.8 km/s vesc) |
| Insolation Flux | 0.0000 S⊕ |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 67.900 LY (20.807 pc) |