HAT-P-30 b
Astrophysical Synthesis & Habitability Characterization
HAT-P-30 b is a confirmed gas giant exoplanet orbiting the star HAT-P-30, located approximately 697.9 light-years (213.99 parsecs) from the Solar System. First announced in 2011 by HATNet using the Transit detection technique (producing an estimated primary transit depth of 1.276% across the stellar disk), this world measures 16.141 Earth radii (1.44 Jupiter radii) and has a measured mass of 263.799 Earth masses (0.83 Jupiter masses). Combining its mass and radius yields a mean bulk density of 0.35 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 1.01 g⊕ (9.9 m/s²), and an escape velocity of 45.2 km/s.
In its orbital architecture around HAT-P-30, HAT-P-30 b completes one full revolution every 2.811 Earth days at a semi-major axis of 0.0419 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 162.2 km/s (compared to Earth's 29.8 km/s). With a near-circular eccentricity of e = 0.04 (ranging from 0.0402 AU at periapsis to 0.0436 AU at apoapsis), the planet experiences minimal orbital distance variation.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 1630 K (+1357°C / +2475°F) and receiving 1,467.96 S⊕ (~1,997,890 W/m²), HAT-P-30 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star HAT-P-30 is classified as a warm F-type star of spectral type F7 with an effective photospheric temperature of 6,304 K, a radius of 1.31 R☉, a mass of 1.55 M☉, an estimated bolometric luminosity of 2.432 L☉. Stellar evolution modeling indicates an estimated stellar age of 1 Gyr and a metallicity of [Fe/H] = 0.13 dex (metal-rich relative to the Sun). From Earth, HAT-P-30 shines at apparent V-band magnitude 10.352 (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: HATNet · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | HAT-P-30 |
| Spectral Type | F7 |
| Effective Temp (Teff) | 6,304 K |
| Stellar Radius | 1.3100 R☉ |
| Stellar Mass | 1.5500 M☉ |
| Bolometric Luminosity | 2.432 L☉ |
| Metallicity [Fe/H] | 0.130 dex |
| Stellar Age | 1.000 Gyr |
| Apparent Magnitude | V: 10.352 · G: 10.300 |
| System Architecture | 2 Stars, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.041900 AU |
| Orbital Period | 2.811 days |
| Mean Orbital Velocity | 162.2 km/s |
| Orbital Eccentricity (e) | 0.04000 |
| Orbital Inclination (i) | 83.6000° |
| Mean Bulk Density | 0.35 g/cm³ (45.2 km/s vesc) |
| Insolation Flux | 1467.9573 S⊕ (~1,997,890 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 697.900 LY (213.985 pc) |