TOI-2447 b
Astrophysical Synthesis & Habitability Characterization
TOI-2447 b is a confirmed gas giant exoplanet orbiting the star TOI-2447, located approximately 485.9 light-years (148.99 parsecs) from the Solar System. First announced in 2024 by Transiting Exoplanet Survey Satellite (TESS) using the Transit detection technique (producing an estimated primary transit depth of 0.7664% across the stellar disk), this world measures 9.606 Earth radii (0.86 Jupiter radii) and has a measured mass of 124.907 Earth masses (0.39 Jupiter masses). Combining its mass and radius yields a mean bulk density of 0.78 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 1.35 g⊕ (13.24 m/s²), and an escape velocity of 40.3 km/s.
In its orbital architecture around TOI-2447, TOI-2447 b completes one full revolution every 69.337 Earth days at a semi-major axis of 0.347 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 54.4 km/s (compared to Earth's 29.8 km/s). Its moderate orbital eccentricity of e = 0.17 carries the world between 0.288 AU at periapsis and 0.406 AU at apoapsis, driving measurable seasonal insolation cycles.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 414 K (+141°C / +286°F) and receiving 44.59 S⊕ (~60,691 W/m²), TOI-2447 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star TOI-2447 is classified as a stellar host with an effective photospheric temperature of 5,730 K, a radius of 1.006 R☉, a mass of 1.034 M☉, an estimated bolometric luminosity of 0.979 L☉. Stellar evolution modeling indicates an estimated stellar age of 2.1 Gyr and a metallicity of [Fe/H] = 0.18 dex (metal-rich relative to the Sun). From Earth, TOI-2447 shines at apparent V-band magnitude 10.507 (faint and requiring research-grade or CCD telescopic photometry) 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-2447 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 5,730 K |
| Stellar Radius | 1.0060 R☉ |
| Stellar Mass | 1.0340 M☉ |
| Bolometric Luminosity | 0.979 L☉ |
| Metallicity [Fe/H] | 0.180 dex |
| Stellar Age | 2.100 Gyr |
| Apparent Magnitude | V: 10.507 · G: 10.440 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.347000 AU |
| Orbital Period | 69.337 days |
| Mean Orbital Velocity | 54.4 km/s |
| Orbital Eccentricity (e) | 0.17000 |
| Orbital Inclination (i) | — |
| Mean Bulk Density | 0.78 g/cm³ (40.3 km/s vesc) |
| Insolation Flux | 44.5933 S⊕ (~60,691 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 485.900 LY (148.987 pc) |