Kepler-849 b
Astrophysical Synthesis & Habitability Characterization
Kepler-849 b is a confirmed gas giant exoplanet orbiting the star Kepler-849, located approximately 2681.4 light-years (822.13 parsecs) from the Solar System. First announced in 2016 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.1654% across the stellar disk), this world measures 8.082 Earth radii (0.72 Jupiter radii) and has a measured mass of 298.759 Earth masses (0.94 Jupiter masses). Combining its mass and radius yields a mean bulk density of 3.12 g/cm³ (an intermediate density indicative of a deep water-ice mantle or dense volatile envelope), a surface gravity of 4.57 g⊕ (44.82 m/s²), and an escape velocity of 68 km/s.
In its orbital architecture around Kepler-849, Kepler-849 b completes one full revolution every 394.625 Earth days (1.08Julian years) at a semi-major axis of 1.137 AU (comparable to the inner terrestrial zone between Venus, Earth at 1.00 AU, and Mars at 1.52 AU). Its mean orbital velocity is approximately 31.3 km/s (compared to Earth's 29.8 km/s). Its moderate orbital eccentricity of e = 0.078 carries the world between 1.0483 AU at periapsis and 1.2257 AU at apoapsis, driving measurable seasonal insolation cycles.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 363 K (+90°C / +194°F) and receiving 2.86 S⊕ (~3,892 W/m²), Kepler-849 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star Kepler-849 is classified as a stellar host with an effective photospheric temperature of 5,950 K, a radius of 1.822 R☉, a mass of 1.259 M☉, an estimated bolometric luminosity of 3.733 L☉. Stellar evolution modeling indicates an estimated stellar age of 4.7 Gyr and a metallicity of [Fe/H] = 0.145 dex (metal-rich relative to the Sun). From Earth, Kepler-849 shines at apparent V-band magnitude 12.878 (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 | Kepler-849 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 5,950 K |
| Stellar Radius | 1.8220 R☉ |
| Stellar Mass | 1.2590 M☉ |
| Bolometric Luminosity | 3.733 L☉ |
| Metallicity [Fe/H] | 0.145 dex |
| Stellar Age | 4.700 Gyr |
| Apparent Magnitude | V: 12.878 · G: 12.836 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 1.137000 AU |
| Orbital Period | 394.625 days |
| Mean Orbital Velocity | 31.3 km/s |
| Orbital Eccentricity (e) | 0.07800 |
| Orbital Inclination (i) | 89.9230° |
| Mean Bulk Density | 3.12 g/cm³ (68 km/s vesc) |
| Insolation Flux | 2.8600 S⊕ (~3,892 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 2681.400 LY (822.134 pc) |