PH1 b
Astrophysical Synthesis & Habitability Characterization
PH1 b is a confirmed gas giant exoplanet orbiting the star PH1, located approximately 3369.7 light-years (1033.16 parsecs) from the Solar System. First announced in 2012 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.1068% across the stellar disk), this world measures 6.18 Earth radii (0.55 Jupiter radii) and has a measured mass of 169 Earth masses (0.53 Jupiter masses). Combining its mass and radius yields a mean bulk density of 3.95 g/cm³ (an intermediate density indicative of a deep water-ice mantle or dense volatile envelope), a surface gravity of 4.42 g⊕ (43.35 m/s²), and an escape velocity of 58.5 km/s.
In its orbital architecture around PH1, PH1 b completes one full revolution every 138.317 Earth days at a semi-major axis of 0.652 AU (situated at an orbital separation between Mercury's 0.39 AU and Venus's 0.72 AU). Its mean orbital velocity is approximately 51.3 km/s (compared to Earth's 29.8 km/s). Its moderate orbital eccentricity of e = 0.0702 carries the world between 0.6062 AU at periapsis and 0.6978 AU at apoapsis, driving measurable seasonal insolation cycles.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 481 K (+208°C / +406°F) and receiving 10.75 S⊕ (~14,634 W/m²), PH1 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star PH1 is classified as a warm F-type star of spectral type F with an effective photospheric temperature of 6,407 K, a radius of 1.734 R☉, a mass of 1.528 M☉, an estimated bolometric luminosity of 4.546 L☉. Stellar evolution modeling indicates an estimated stellar age of 2 Gyr and a metallicity of [Fe/H] = 0.21 dex (metal-rich relative to the Sun). From Earth, PH1 shines at apparent V-band magnitude 13.841 (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: Kepler · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | PH1 |
| Spectral Type | F |
| Effective Temp (Teff) | 6,407 K |
| Stellar Radius | 1.7340 R☉ |
| Stellar Mass | 1.5280 M☉ |
| Bolometric Luminosity | 4.546 L☉ |
| Metallicity [Fe/H] | 0.210 dex |
| Stellar Age | 2.000 Gyr |
| Apparent Magnitude | V: 13.841 · G: 13.699 |
| System Architecture | 4 Stars, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.652000 AU |
| Orbital Period | 138.317 days |
| Mean Orbital Velocity | 51.3 km/s |
| Orbital Eccentricity (e) | 0.07020 |
| Orbital Inclination (i) | 90.0500° |
| Mean Bulk Density | 3.95 g/cm³ (58.5 km/s vesc) |
| Insolation Flux | 10.7524 S⊕ (~14,634 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 3369.700 LY (1033.160 pc) |