HD 41004 B b
Astrophysical Synthesis & Habitability Characterization
HD 41004 B b is a confirmed gas giant exoplanet orbiting the star HD 41004 B, located approximately 135.5 light-years (41.55 parsecs) from the Solar System. First announced in 2003 by La Silla Observatory using the Radial Velocity detection technique (measuring periodic Doppler reflex motion in the host star's spectrum), this world measures 12.1 Earth radii (1.08 Jupiter radii) and has a measured mass of 5838.29 Earth masses (18.37 Jupiter masses). Combining its mass and radius yields a mean bulk density of 18.17 g/cm³ (an iron-enriched, high-compression rocky core), a surface gravity of 39.88 g⊕ (391.09 m/s²), and an escape velocity of 245.7 km/s.
In its orbital architecture around HD 41004 B, HD 41004 B b completes one full revolution every 1.328 Earth days. Its moderate orbital eccentricity of e = 0.081 driving measurable seasonal insolation cycles.
☁️ Atmospheric Regime (Volatile / Gas Envelope): With a radius of 12.100 R⊕, HD 41004 B 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 41004 B is classified as a low-mass red dwarf of spectral type M2 V with an effective photospheric temperature of 5,036 K, a radius of 1.0414 R☉, a mass of 0.4 M☉, an estimated bolometric luminosity of 0.626 L☉. From Earth, HD 41004 B shines at apparent V-band magnitude 8.608 (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 41004 B |
| Spectral Type | M2 V |
| Effective Temp (Teff) | 5,036 K |
| Stellar Radius | 1.0414 R☉ |
| Stellar Mass | 0.4000 M☉ |
| Bolometric Luminosity | 0.626 L☉ |
| Metallicity [Fe/H] | — |
| Stellar Age | — |
| Apparent Magnitude | V: 8.608 · G: 8.376 |
| System Architecture | 2 Stars, 2 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | — |
| Orbital Period | 1.328 days |
| Orbital Eccentricity (e) | 0.08100 |
| Orbital Inclination (i) | — |
| Mean Bulk Density | 18.17 g/cm³ (245.7 km/s vesc) |
| Insolation Flux | — |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 135.500 LY (41.550 pc) |