GJ 2030 b
Astrophysical Synthesis & Habitability Characterization
GJ 2030 b is a confirmed sub-neptune exoplanet orbiting the star GJ 2030, located approximately 120.9 light-years (37.08 parsecs) from the Solar System. First announced in 2022 by Multiple Observatories using the Radial Velocity detection technique (measuring periodic Doppler reflex motion in the host star's spectrum), this world measures 2.03 Earth radii and has a measured mass of 4.767 Earth masses. Combining its mass and radius yields a mean bulk density of 3.14 g/cm³ (an intermediate density indicative of a deep water-ice mantle or dense volatile envelope), a surface gravity of 1.16 g⊕ (11.38 m/s²), and an escape velocity of 17.1 km/s.
In its orbital architecture around GJ 2030, GJ 2030 b completes one full revolution every 2.381 Earth days at a semi-major axis of 0.034 AU (an ultra-close orbit less than one-seventh of Mercury's 0.387 AU distance from the Sun, where strong stellar tidal forces typically induce synchronous rotation). Its mean orbital velocity is approximately 155.3 km/s (compared to Earth's 29.8 km/s). Its moderate orbital eccentricity of e = 0.239 carries the world between 0.0259 AU at periapsis and 0.0421 AU at apoapsis, driving measurable seasonal insolation cycles.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 2147 K (+1874°C / +3405°F) and receiving 3,542.76 S⊕ (~4,821,695 W/m²), GJ 2030 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star GJ 2030 is classified as a stellar host with an effective photospheric temperature of 5,485 K, a radius of 2.241 R☉, a mass of 0.96 M☉, an estimated bolometric luminosity of 4.078 L☉. Stellar evolution modeling indicates a metallicity of [Fe/H] = -0.4 dex (metal-poor relative to the Sun). From Earth, GJ 2030 shines at apparent V-band magnitude 6.209 (accessible to binoculars and small amateur telescopes) in the Southern celestial hemisphere. The GJ 2030 system is a multi-planet architecture hosting 2 confirmed worlds, with GJ 2030 b sharing its stellar neighborhood alongside GJ 2030 c.
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 2030 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 5,485 K |
| Stellar Radius | 2.2410 R☉ |
| Stellar Mass | 0.9600 M☉ |
| Bolometric Luminosity | 4.078 L☉ |
| Metallicity [Fe/H] | -0.400 dex |
| Stellar Age | — |
| Apparent Magnitude | V: 6.209 · G: 6.021 |
| System Architecture | 1 Star, 2 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.034000 AU |
| Orbital Period | 2.381 days |
| Mean Orbital Velocity | 155.3 km/s |
| Orbital Eccentricity (e) | 0.23900 |
| Orbital Inclination (i) | — |
| Mean Bulk Density | 3.14 g/cm³ (17.1 km/s vesc) |
| Insolation Flux | 3542.7587 S⊕ (~4,821,695 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 120.900 LY (37.079 pc) |