Kepler-799 b
Astrophysical Synthesis & Habitability Characterization
Kepler-799 b is a confirmed gas giant exoplanet orbiting the star Kepler-799, located approximately 4922 light-years (1509.08 parsecs) from the Solar System. First announced in 2016 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.46% across the stellar disk), this world measures 6.88 Earth radii (0.61 Jupiter radii) and has a measured mass of 37.9 Earth masses (0.12 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 0.8 g⊕ (7.85 m/s²), and an escape velocity of 26.3 km/s.
In its orbital architecture around Kepler-799, Kepler-799 b completes one full revolution every 133.461 Earth days at a semi-major axis of 0.5167 AU (situated at an orbital separation between Mercury's 0.39 AU and Venus's 0.72 AU). Its mean orbital velocity is approximately 42.1 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 433 K (+160°C / +320°F) and receiving 6.36 S⊕ (~8,651 W/m²), Kepler-799 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star Kepler-799 is classified as a stellar host with an effective photospheric temperature of 5,681 K, a radius of 0.93 R☉, a mass of 0.95 M☉, an estimated bolometric luminosity of 0.808 L☉. Stellar evolution modeling indicates an estimated stellar age of 3.98 Gyr and a metallicity of [Fe/H] = -0.07 dex (near-solar heavy-element abundance). From Earth, Kepler-799 shines at apparent V-band magnitude 15.166 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere. The Kepler-799 system is a multi-planet architecture hosting 2 confirmed worlds, with Kepler-799 b sharing its stellar neighborhood alongside Kepler-799 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: Kepler · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | Kepler-799 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 5,681 K |
| Stellar Radius | 0.9300 R☉ |
| Stellar Mass | 0.9500 M☉ |
| Bolometric Luminosity | 0.808 L☉ |
| Metallicity [Fe/H] | -0.070 dex |
| Stellar Age | 3.980 Gyr |
| Apparent Magnitude | V: 15.166 |
| System Architecture | 1 Star, 2 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.516700 AU |
| Orbital Period | 133.461 days |
| Mean Orbital Velocity | 42.1 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 89.8400° |
| Mean Bulk Density | 0.64 g/cm³ (26.3 km/s vesc) |
| Insolation Flux | 6.3560 S⊕ (~8,651 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 4922.000 LY (1509.084 pc) |