HD 194490 b
Astrophysical Synthesis & Habitability Characterization
HD 194490 b is a confirmed gas giant exoplanet orbiting the star HD 194490, located approximately 261.7 light-years (80.24 parsecs) from the Solar System. First announced in 2022 by Multiple Observatories using the Radial Velocity detection technique (measuring periodic Doppler reflex motion in the host star's spectrum), this world measures 12.4 Earth radii (1.11 Jupiter radii) and has a measured mass of 3561.903 Earth masses (11.21 Jupiter masses). Combining its mass and radius yields a mean bulk density of 10.3 g/cm³ (an iron-enriched, high-compression rocky core), a surface gravity of 23.17 g⊕ (227.22 m/s²), and an escape velocity of 189.6 km/s.
In its orbital architecture around HD 194490, HD 194490 b completes one full revolution every 13092.183 Earth days (35.84Julian years) at a semi-major axis of 11.116 AU (a wide outer-system orbit beyond Jupiter's 5.20 AU distance in our Solar System). Its mean orbital velocity is approximately 9.2 km/s (compared to Earth's 29.8 km/s). The planet follows a highly eccentric trajectory (e = 0.251, swinging from 8.3259 AU at periapsis out to 13.9061 AU at apoapsis), pointing to past dynamical scattering or secular gravitational perturbations.
❄️ Thermal Regime (Cryogenic Zone): With an equilibrium temperature of 91 K (-182°C / -296°F) and an incident flux of 0.01 S⊕ (~16 W/m²), surface water and volatile species on HD 194490 b would remain locked in cryogenic ice phases unless warmed by subsurface tidal or radiogenic heating.
The host star HD 194490 is classified as a stellar host with an effective photospheric temperature of 5,861 K, a radius of 1.1491 R☉, a mass of 1.06 M☉, an estimated bolometric luminosity of 1.398 L☉. Stellar evolution modeling indicates a metallicity of [Fe/H] = 0.08 dex (metal-rich relative to the Sun). From Earth, HD 194490 shines at apparent V-band magnitude 8.99 (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: Multiple Observatories · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | HD 194490 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 5,861 K |
| Stellar Radius | 1.1491 R☉ |
| Stellar Mass | 1.0600 M☉ |
| Bolometric Luminosity | 1.398 L☉ |
| Metallicity [Fe/H] | 0.080 dex |
| Stellar Age | — |
| Apparent Magnitude | V: 8.990 · G: 8.827 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 11.116000 AU |
| Orbital Period | 13092.183 days |
| Mean Orbital Velocity | 9.2 km/s |
| Orbital Eccentricity (e) | 0.25100 |
| Orbital Inclination (i) | 57.9900° |
| Mean Bulk Density | 10.3 g/cm³ (189.6 km/s vesc) |
| Insolation Flux | 0.0114 S⊕ (~16 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 261.700 LY (80.235 pc) |