HD 94890 b
Astrophysical Synthesis & Habitability Characterization
HD 94890 b is a confirmed gas giant exoplanet orbiting the star HD 94890, located approximately 201.2 light-years (61.7 parsecs) from the Solar System. First announced in 2025 by La Silla Observatory using the Radial Velocity detection technique (measuring periodic Doppler reflex motion in the host star's spectrum), this world measures 13.3 Earth radii (1.19 Jupiter radii) and has a measured mass of 676.975 Earth masses (2.13 Jupiter masses). Combining its mass and radius yields a mean bulk density of 1.59 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 3.83 g⊕ (37.56 m/s²), and an escape velocity of 79.8 km/s.
In its orbital architecture around HD 94890, HD 94890 b completes one full revolution every 824.61 Earth days (2.26Julian 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 27.3 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.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 534 K (+261°C / +502°F) and receiving 13.54 S⊕ (~18,425 W/m²), HD 94890 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star HD 94890 is classified as an orange K-type star of spectral type K0 III with an effective photospheric temperature of 4,867 K, a radius of 10.71 R☉, a mass of 1.74 M☉, an estimated bolometric luminosity of 57.745 L☉. Stellar evolution modeling indicates a metallicity of [Fe/H] = -0.02 dex (near-solar heavy-element abundance). From Earth, HD 94890 shines at apparent V-band magnitude 4.6 (visible to the unaided human eye under dark skies) in the Southern celestial hemisphere. The HD 94890 system is a multi-planet architecture hosting 2 confirmed worlds, with HD 94890 b sharing its stellar neighborhood alongside HD 94890 c.
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 94890 |
| Spectral Type | K0 III |
| Effective Temp (Teff) | 4,867 K |
| Stellar Radius | 10.7100 R☉ |
| Stellar Mass | 1.7400 M☉ |
| Bolometric Luminosity | 57.745 L☉ |
| Metallicity [Fe/H] | -0.020 dex |
| Stellar Age | — |
| Apparent Magnitude | V: 4.600 · G: 4.326 |
| System Architecture | 1 Star, 2 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 2.070000 AU |
| Orbital Period | 824.61 days |
| Mean Orbital Velocity | 27.3 km/s |
| Orbital Eccentricity (e) | 0.22000 |
| Orbital Inclination (i) | — |
| Mean Bulk Density | 1.59 g/cm³ (79.8 km/s vesc) |
| Insolation Flux | 13.5382 S⊕ (~18,425 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 201.200 LY (61.701 pc) |