K2-30 b
Astrophysical Synthesis & Habitability Characterization
K2-30 b is a confirmed gas giant exoplanet orbiting the star K2-30, located approximately 1086.2 light-years (333.04 parsecs) from the Solar System. First announced in 2016 by K2 using the Transit detection technique (producing an estimated primary transit depth of 1.6003% across the stellar disk), this world measures 11.646 Earth radii (1.04 Jupiter radii) and has a measured mass of 184.024 Earth masses (0.58 Jupiter masses). Combining its mass and radius yields a mean bulk density of 0.64 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 1.36 g⊕ (13.34 m/s²), and an escape velocity of 44.5 km/s.
In its orbital architecture around K2-30, K2-30 b completes one full revolution every 4.099 Earth days at a semi-major axis of 0.04839 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 128.4 km/s (compared to Earth's 29.8 km/s). The orbit is modeled as circular (e = 0.00), maintaining a constant stellar distance throughout its year.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 1092 K (+819°C / +1506°F) and receiving 299.00 S⊕ (~406,939 W/m²), K2-30 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star K2-30 is classified as a solar-type yellow star of spectral type G6 V with an effective photospheric temperature of 5,425 K, a radius of 0.844 R☉, a mass of 0.9 M☉, an estimated bolometric luminosity of 0.554 L☉. Stellar evolution modeling indicates an estimated stellar age of 3.9 Gyr and a metallicity of [Fe/H] = -0.15 dex (metal-poor relative to the Sun). From Earth, K2-30 shines at apparent V-band magnitude 13.547 (faint and requiring research-grade or CCD telescopic photometry) 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: K2 · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | K2-30 |
| Spectral Type | G6 V |
| Effective Temp (Teff) | 5,425 K |
| Stellar Radius | 0.8440 R☉ |
| Stellar Mass | 0.9000 M☉ |
| Bolometric Luminosity | 0.554 L☉ |
| Metallicity [Fe/H] | -0.150 dex |
| Stellar Age | 3.900 Gyr |
| Apparent Magnitude | V: 13.547 · G: 13.206 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.048390 AU |
| Orbital Period | 4.099 days |
| Mean Orbital Velocity | 128.4 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 86.9200° |
| Mean Bulk Density | 0.64 g/cm³ (44.5 km/s vesc) |
| Insolation Flux | 299.0000 S⊕ (~406,939 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 1086.200 LY (333.042 pc) |