HD 197037 b
Astrophysical Synthesis & Habitability Characterization
HD 197037 b is a confirmed gas giant exoplanet orbiting the star HD 197037, located approximately 108.3 light-years (33.19 parsecs) from the Solar System. First announced in 2012 by McDonald Observatory using the Radial Velocity detection technique (measuring periodic Doppler reflex motion in the host star's spectrum), this world measures 13.9 Earth radii (1.24 Jupiter radii) and has a measured mass of 251 Earth masses (0.79 Jupiter masses). Combining its mass and radius yields a mean bulk density of 0.52 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 1.3 g⊕ (12.75 m/s²), and an escape velocity of 47.5 km/s.
In its orbital architecture around HD 197037, HD 197037 b completes one full revolution every 1035.7 Earth days (2.84Julian years) at a semi-major axis of 2.07 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 21.7 km/s (compared to Earth's 29.8 km/s). Its moderate orbital eccentricity of e = 0.22 carries the world between 1.6146 AU at periapsis and 2.5254 AU at apoapsis, driving measurable seasonal insolation cycles.
☁️ Atmospheric Regime (Volatile / Gas Envelope): With a radius of 13.900 R⊕, HD 197037 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 197037 is classified as a warm F-type star of spectral type F7 V with an effective photospheric temperature of 6,150 K, a radius of 1.105 R☉, a mass of 1.11 M☉, an estimated bolometric luminosity of 1.567 L☉. Stellar evolution modeling indicates an estimated stellar age of 1.9 Gyr and a metallicity of [Fe/H] = -0.2 dex (metal-poor relative to the Sun). From Earth, HD 197037 shines at apparent V-band magnitude 6.823 (accessible to binoculars and small amateur telescopes) 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: McDonald Observatory · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | HD 197037 |
| Spectral Type | F7 V |
| Effective Temp (Teff) | 6,150 K |
| Stellar Radius | 1.1050 R☉ |
| Stellar Mass | 1.1100 M☉ |
| Bolometric Luminosity | 1.567 L☉ |
| Metallicity [Fe/H] | -0.200 dex |
| Stellar Age | 1.900 Gyr |
| Apparent Magnitude | V: 6.823 · G: 6.671 |
| System Architecture | 2 Stars, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 2.070000 AU |
| Orbital Period | 1035.7 days |
| Mean Orbital Velocity | 21.7 km/s |
| Orbital Eccentricity (e) | 0.22000 |
| Orbital Inclination (i) | — |
| Mean Bulk Density | 0.52 g/cm³ (47.5 km/s vesc) |
| Insolation Flux | 0.4042 S⊕ (~550 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 108.300 LY (33.194 pc) |