HD 7449 b
Astrophysical Synthesis & Habitability Characterization
HD 7449 b is a confirmed gas giant exoplanet orbiting the star HD 7449, located approximately 126.1 light-years (38.66 parsecs) from the Solar System. First announced in 2011 by La Silla Observatory using the Radial Velocity detection technique (measuring periodic Doppler reflex motion in the host star's spectrum), this world measures 12.6 Earth radii (1.12 Jupiter radii) and has a measured mass of 2597.929 Earth masses (8.17 Jupiter masses). Combining its mass and radius yields a mean bulk density of 7.16 g/cm³ (an iron-enriched, high-compression rocky core), a surface gravity of 16.36 g⊕ (160.44 m/s²), and an escape velocity of 160.6 km/s.
In its orbital architecture around HD 7449, HD 7449 b completes one full revolution every 1270.552 Earth days (3.48Julian years) at a semi-major axis of 2.438 AU (corresponding to the middle-system regime between Mars at 1.52 AU and Jupiter at 5.20 AU). Its mean orbital velocity is approximately 20.9 km/s (compared to Earth's 29.8 km/s). The planet follows a highly eccentric trajectory (e = 0.752, swinging from 0.6046 AU at periapsis out to 4.2714 AU at apoapsis), pointing to past dynamical scattering or secular gravitational perturbations.
☁️ Atmospheric Regime (Volatile / Gas Envelope): With a radius of 12.600 R⊕, HD 7449 b exceeds the empirical ~1.8–2.2 R⊕ Fulton radius valley threshold, indicating a substantial hydrogen-helium or supercritical volatile envelope without a conventional solid terrestrial surface.
The host star HD 7449 is classified as a warm F-type star of spectral type F8 V with an effective photospheric temperature of 6,024 K, a radius of 0.97 R☉, a mass of 1.196 M☉, an estimated bolometric luminosity of 1.112 L☉. Stellar evolution modeling indicates an estimated stellar age of 2.1 Gyr and a metallicity of [Fe/H] = -0.105 dex (metal-poor relative to the Sun). From Earth, HD 7449 shines at apparent V-band magnitude 7.5 (accessible to binoculars and small amateur telescopes) in the Southern 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: La Silla Observatory · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | HD 7449 |
| Spectral Type | F8 V |
| Effective Temp (Teff) | 6,024 K |
| Stellar Radius | 0.9700 R☉ |
| Stellar Mass | 1.1960 M☉ |
| Bolometric Luminosity | 1.112 L☉ |
| Metallicity [Fe/H] | -0.105 dex |
| Stellar Age | 2.100 Gyr |
| Apparent Magnitude | V: 7.500 · G: 7.350 |
| System Architecture | 2 Stars, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 2.438000 AU |
| Orbital Period | 1270.552 days |
| Mean Orbital Velocity | 20.9 km/s |
| Orbital Eccentricity (e) | 0.75200 |
| Orbital Inclination (i) | 171.6310° |
| Mean Bulk Density | 7.16 g/cm³ (160.6 km/s vesc) |
| Insolation Flux | 0.2125 S⊕ (~289 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 126.100 LY (38.662 pc) |