HAT-P-49 b
Astrophysical Synthesis & Habitability Characterization
HAT-P-49 b is a confirmed gas giant exoplanet orbiting the star HAT-P-49, located approximately 1142.7 light-years (350.35 parsecs) from the Solar System. First announced in 2014 by HATNet using the Transit detection technique (producing an estimated primary transit depth of 0.6291% across the stellar disk), this world measures 17.822 Earth radii (1.59 Jupiter radii) and has a measured mass of 699.226 Earth masses (2.2 Jupiter masses). Combining its mass and radius yields a mean bulk density of 0.68 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 2.2 g⊕ (21.57 m/s²), and an escape velocity of 70.1 km/s.
In its orbital architecture around HAT-P-49, HAT-P-49 b completes one full revolution every 2.692 Earth days at a semi-major axis of 0.04378 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 177 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 2131 K (+1858°C / +3376°F) and receiving 4,392.03 S⊕ (~5,977,553 W/m²), HAT-P-49 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star HAT-P-49 is classified as a warm F-type star of spectral type F3 with an effective photospheric temperature of 6,820 K, a radius of 2.06 R☉, a mass of 2.22 M☉, an estimated bolometric luminosity of 8.237 L☉. Stellar evolution modeling indicates an estimated stellar age of 1.5 Gyr and a metallicity of [Fe/H] = 0.07 dex (metal-rich relative to the Sun). From Earth, HAT-P-49 shines at apparent V-band magnitude 10.205 (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-49 |
| Spectral Type | F3 |
| Effective Temp (Teff) | 6,820 K |
| Stellar Radius | 2.0600 R☉ |
| Stellar Mass | 2.2200 M☉ |
| Bolometric Luminosity | 8.237 L☉ |
| Metallicity [Fe/H] | 0.070 dex |
| Stellar Age | 1.500 Gyr |
| Apparent Magnitude | V: 10.205 · G: 10.207 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.043780 AU |
| Orbital Period | 2.692 days |
| Mean Orbital Velocity | 177 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 86.2000° |
| Mean Bulk Density | 0.68 g/cm³ (70.1 km/s vesc) |
| Insolation Flux | 4392.0300 S⊕ (~5,977,553 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 1142.700 LY (350.351 pc) |