HD 37605 c
Astrophysical Synthesis & Habitability Characterization
HD 37605 c is a confirmed gas giant exoplanet orbiting the star HD 37605, located approximately 152.6 light-years (46.79 parsecs) from the Solar System. First announced in 2012 by Multiple Observatories using the Radial Velocity detection technique (measuring periodic Doppler reflex motion in the host star's spectrum), this world measures 13.1 Earth radii (1.17 Jupiter radii) and has a measured mass of 1013.878 Earth masses (3.19 Jupiter masses). Combining its mass and radius yields a mean bulk density of 2.49 g/cm³ (an intermediate density indicative of a deep water-ice mantle or dense volatile envelope), a surface gravity of 5.91 g⊕ (57.96 m/s²), and an escape velocity of 98.4 km/s.
In its orbital architecture around HD 37605, HD 37605 c completes one full revolution every 2720 Earth days (7.45Julian years) at a semi-major axis of 3.74 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 15 km/s (compared to Earth's 29.8 km/s). With a near-circular eccentricity of e = 0.03 (ranging from 3.6278 AU at periapsis to 3.8522 AU at apoapsis), the planet experiences minimal orbital distance variation.
❄️ Thermal Regime (Cryogenic Zone): With an equilibrium temperature of 127 K (-146°C / -231°F) and an incident flux of 0.04 S⊕ (~59 W/m²), surface water and volatile species on HD 37605 c would remain locked in cryogenic ice phases unless warmed by subsurface tidal or radiogenic heating.
The host star HD 37605 is classified as an orange K-type star of spectral type K0 with an effective photospheric temperature of 5,329 K, a radius of 0.91 R☉, a mass of 0.94 M☉, an estimated bolometric luminosity of 0.599 L☉. Stellar evolution modeling indicates an estimated stellar age of 5.65 Gyr and a metallicity of [Fe/H] = 0.27 dex (metal-rich relative to the Sun). From Earth, HD 37605 shines at apparent V-band magnitude 8.67 (accessible to binoculars and small amateur telescopes) in the Northern celestial hemisphere. The HD 37605 system is a multi-planet architecture hosting 2 confirmed worlds, with HD 37605 c sharing its stellar neighborhood alongside HD 37605 b.
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: Multiple Observatories · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | HD 37605 |
| Spectral Type | K0 |
| Effective Temp (Teff) | 5,329 K |
| Stellar Radius | 0.9100 R☉ |
| Stellar Mass | 0.9400 M☉ |
| Bolometric Luminosity | 0.599 L☉ |
| Metallicity [Fe/H] | 0.270 dex |
| Stellar Age | 5.650 Gyr |
| Apparent Magnitude | V: 8.670 · G: 8.462 |
| System Architecture | 1 Star, 2 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 3.740000 AU |
| Orbital Period | 2720 days |
| Mean Orbital Velocity | 15 km/s |
| Orbital Eccentricity (e) | 0.03000 |
| Orbital Inclination (i) | — |
| Mean Bulk Density | 2.49 g/cm³ (98.4 km/s vesc) |
| Insolation Flux | 0.0431 S⊕ (~59 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 152.600 LY (46.786 pc) |