HD 110113 b
Astrophysical Synthesis & Habitability Characterization
HD 110113 b is a confirmed sub-neptune exoplanet orbiting the star HD 110113, located approximately 346.7 light-years (106.31 parsecs) from the Solar System. First announced in 2021 by Transiting Exoplanet Survey Satellite (TESS) using the Transit detection technique (producing an estimated primary transit depth of 0.0377% across the stellar disk), this world measures 2.05 Earth radii and has a measured mass of 4.55 Earth masses. Combining its mass and radius yields a mean bulk density of 2.91 g/cm³ (an intermediate density indicative of a deep water-ice mantle or dense volatile envelope), a surface gravity of 1.08 g⊕ (10.59 m/s²), and an escape velocity of 16.7 km/s.
In its orbital architecture around HD 110113, HD 110113 b completes one full revolution every 2.541 Earth days at a semi-major axis of 0.035 AU (an ultra-close orbit less than one-seventh of Mercury's 0.387 AU distance from the Sun, where strong stellar tidal forces typically induce synchronous rotation). Its mean orbital velocity is approximately 149.8 km/s (compared to Earth's 29.8 km/s). Its moderate orbital eccentricity of e = 0.093 carries the world between 0.0317 AU at periapsis and 0.0383 AU at apoapsis, driving measurable seasonal insolation cycles.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 1371 K (+1098°C / +2008°F) and receiving 735.49 S⊕ (~1,001,002 W/m²), HD 110113 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star HD 110113 is classified as a solar-type yellow star of spectral type G with an effective photospheric temperature of 5,732 K, a radius of 0.968 R☉, a mass of 0.997 M☉, an estimated bolometric luminosity of 0.908 L☉. Stellar evolution modeling indicates an estimated stellar age of 4 Gyr and a metallicity of [Fe/H] = 0.14 dex (metal-rich relative to the Sun). From Earth, HD 110113 shines at apparent V-band magnitude 10.09 (faint and requiring research-grade or CCD telescopic photometry) in the Southern celestial hemisphere. The HD 110113 system is a multi-planet architecture hosting 2 confirmed worlds, with HD 110113 b sharing its stellar neighborhood alongside HD 110113 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 | HD 110113 |
| Spectral Type | G |
| Effective Temp (Teff) | 5,732 K |
| Stellar Radius | 0.9680 R☉ |
| Stellar Mass | 0.9970 M☉ |
| Bolometric Luminosity | 0.908 L☉ |
| Metallicity [Fe/H] | 0.140 dex |
| Stellar Age | 4.000 Gyr |
| Apparent Magnitude | V: 10.090 · G: 9.910 |
| System Architecture | 1 Star, 2 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.035000 AU |
| Orbital Period | 2.541 days |
| Mean Orbital Velocity | 149.8 km/s |
| Orbital Eccentricity (e) | 0.09300 |
| Orbital Inclination (i) | 87.6900° |
| Mean Bulk Density | 2.91 g/cm³ (16.7 km/s vesc) |
| Insolation Flux | 735.4900 S⊕ (~1,001,002 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 346.700 LY (106.307 pc) |