TOI-481 b
Astrophysical Synthesis & Habitability Characterization
TOI-481 b is a confirmed gas giant exoplanet orbiting the star TOI-481, located approximately 585 light-years (179.37 parsecs) from the Solar System. First announced in 2020 by Transiting Exoplanet Survey Satellite (TESS) using the Transit detection technique (producing an estimated primary transit depth of 0.3756% across the stellar disk), this world measures 11.097 Earth radii (0.99 Jupiter radii) and has a measured mass of 486.28 Earth masses (1.53 Jupiter masses). Combining its mass and radius yields a mean bulk density of 1.96 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 3.95 g⊕ (38.74 m/s²), and an escape velocity of 74 km/s.
In its orbital architecture around TOI-481, TOI-481 b completes one full revolution every 10.331 Earth days at a semi-major axis of 0.097 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 102.1 km/s (compared to Earth's 29.8 km/s). Its moderate orbital eccentricity of e = 0.153 carries the world between 0.0822 AU at periapsis and 0.1118 AU at apoapsis, driving measurable seasonal insolation cycles.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 1370 K (+1097°C / +2007°F) and receiving 253.13 S⊕ (~344,504 W/m²), TOI-481 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star TOI-481 is classified as a solar-type yellow star of spectral type G with an effective photospheric temperature of 5,735 K, a radius of 1.66 R☉, a mass of 1.14 M☉, an estimated bolometric luminosity of 2.674 L☉. Stellar evolution modeling indicates an estimated stellar age of 6.7 Gyr and a metallicity of [Fe/H] = 0.26 dex (metal-rich relative to the Sun). From Earth, TOI-481 shines at apparent V-band magnitude 9.972 (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: Transiting Exoplanet Survey Satellite (TESS) · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | TOI-481 |
| Spectral Type | G |
| Effective Temp (Teff) | 5,735 K |
| Stellar Radius | 1.6600 R☉ |
| Stellar Mass | 1.1400 M☉ |
| Bolometric Luminosity | 2.674 L☉ |
| Metallicity [Fe/H] | 0.260 dex |
| Stellar Age | 6.700 Gyr |
| Apparent Magnitude | V: 9.972 · G: 9.847 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.097000 AU |
| Orbital Period | 10.331 days |
| Mean Orbital Velocity | 102.1 km/s |
| Orbital Eccentricity (e) | 0.15300 |
| Orbital Inclination (i) | 89.2000° |
| Mean Bulk Density | 1.96 g/cm³ (74 km/s vesc) |
| Insolation Flux | 253.1260 S⊕ (~344,504 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 585.000 LY (179.366 pc) |