HIP 8152 b
Astrophysical Synthesis & Habitability Characterization
HIP 8152 b is a confirmed sub-neptune exoplanet orbiting the star HIP 8152, located approximately 331.7 light-years (101.69 parsecs) from the Solar System. First announced in 2023 by Transiting Exoplanet Survey Satellite (TESS) using the Transit detection technique (producing an estimated primary transit depth of 0.0586% across the stellar disk), this world measures 2.536 Earth radii and has a measured mass of 8.9 Earth masses. Combining its mass and radius yields a mean bulk density of 3.01 g/cm³ (an intermediate density indicative of a deep water-ice mantle or dense volatile envelope), a surface gravity of 1.38 g⊕ (13.53 m/s²), and an escape velocity of 21 km/s.
In its orbital architecture around HIP 8152, HIP 8152 b completes one full revolution every 10.751 Earth days at a semi-major axis of 0.093 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 94.1 km/s (compared to Earth's 29.8 km/s). The orbit is modeled as circular (e = 0.00), maintaining a constant stellar distance throughout its year.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 795 K (+522°C / +972°F) and receiving 88.90 S⊕ (~120,993 W/m²), HIP 8152 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star HIP 8152 is classified as a stellar host with an effective photospheric temperature of 5,618 K, a radius of 0.9603 R☉, a mass of 0.9373 M☉, an estimated bolometric luminosity of 0.824 L☉. Stellar evolution modeling indicates an estimated stellar age of 6 Gyr and a metallicity of [Fe/H] = 0.007 dex (near-solar heavy-element abundance). From Earth, HIP 8152 shines at apparent V-band magnitude 10.07 (faint and requiring research-grade or CCD telescopic photometry) in the Southern celestial hemisphere. The HIP 8152 system is a multi-planet architecture hosting 2 confirmed worlds, with HIP 8152 b sharing its stellar neighborhood alongside HIP 8152 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: Transiting Exoplanet Survey Satellite (TESS) · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | HIP 8152 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 5,618 K |
| Stellar Radius | 0.9603 R☉ |
| Stellar Mass | 0.9373 M☉ |
| Bolometric Luminosity | 0.824 L☉ |
| Metallicity [Fe/H] | 0.007 dex |
| Stellar Age | 6.000 Gyr |
| Apparent Magnitude | V: 10.070 · G: 9.907 |
| System Architecture | 1 Star, 2 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.093000 AU |
| Orbital Period | 10.751 days |
| Mean Orbital Velocity | 94.1 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | — |
| Mean Bulk Density | 3.01 g/cm³ (21 km/s vesc) |
| Insolation Flux | 88.9000 S⊕ (~120,993 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 331.700 LY (101.694 pc) |