HD 73344 b
Astrophysical Synthesis & Habitability Characterization
HD 73344 b is a confirmed sub-neptune exoplanet orbiting the star HD 73344, located approximately 115 light-years (35.26 parsecs) from the Solar System. First announced in 2024 by K2 using the Transit detection technique (producing an estimated primary transit depth of 0.047% across the stellar disk), this world measures 2.884 Earth radii and has a measured mass of 10.48 Earth masses. Combining its mass and radius yields a mean bulk density of 2.41 g/cm³ (an intermediate density indicative of a deep water-ice mantle or dense volatile envelope), a surface gravity of 1.26 g⊕ (12.36 m/s²), and an escape velocity of 21.3 km/s.
In its orbital architecture around HD 73344, HD 73344 b completes one full revolution every 15.611 Earth days at a semi-major axis of 0.131 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 91.3 km/s (compared to Earth's 29.8 km/s). With a near-circular eccentricity of e = 0.03 (ranging from 0.1271 AU at periapsis to 0.1349 AU at apoapsis), the planet experiences minimal orbital distance variation.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 911 K (+638°C / +1180°F) and receiving 111.97 S⊕ (~152,395 W/m²), HD 73344 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star HD 73344 is classified as a warm F-type star of spectral type F6 V with an effective photospheric temperature of 6,253 K, a radius of 1.22 R☉, a mass of 1.2 M☉, an estimated bolometric luminosity of 2.042 L☉. Stellar evolution modeling indicates an estimated stellar age of 1.15 Gyr and a metallicity of [Fe/H] = 0.143 dex (metal-rich relative to the Sun). From Earth, HD 73344 shines at apparent V-band magnitude 6.894 (accessible to binoculars and small amateur telescopes) in the Northern celestial hemisphere. The HD 73344 system is a multi-planet architecture hosting 3 confirmed worlds, with HD 73344 b sharing its stellar neighborhood alongside HD 73344 c, HD 73344 d.
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: K2 · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | HD 73344 |
| Spectral Type | F6 V |
| Effective Temp (Teff) | 6,253 K |
| Stellar Radius | 1.2200 R☉ |
| Stellar Mass | 1.2000 M☉ |
| Bolometric Luminosity | 2.042 L☉ |
| Metallicity [Fe/H] | 0.143 dex |
| Stellar Age | 1.150 Gyr |
| Apparent Magnitude | V: 6.894 · G: 6.747 |
| System Architecture | 1 Star, 3 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.131000 AU |
| Orbital Period | 15.611 days |
| Mean Orbital Velocity | 91.3 km/s |
| Orbital Eccentricity (e) | 0.03000 |
| Orbital Inclination (i) | 88.0820° |
| Mean Bulk Density | 2.41 g/cm³ (21.3 km/s vesc) |
| Insolation Flux | 111.9729 S⊕ (~152,395 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 115.000 LY (35.260 pc) |