TOI-3894 b
Astrophysical Synthesis & Habitability Characterization
TOI-3894 b is a confirmed gas giant exoplanet orbiting the star TOI-3894, located approximately 1361.3 light-years (417.37 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 0.865% across the stellar disk), this world measures 15.278 Earth radii (1.36 Jupiter radii) and has a measured mass of 260.619 Earth masses (0.82 Jupiter masses). Combining its mass and radius yields a mean bulk density of 0.4 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 1.12 g⊕ (10.98 m/s²), and an escape velocity of 46.2 km/s.
In its orbital architecture around TOI-3894, TOI-3894 b completes one full revolution every 4.335 Earth days at a semi-major axis of 0.05354 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 134.4 km/s (compared to Earth's 29.8 km/s). Its moderate orbital eccentricity of e = 0.05 carries the world between 0.0509 AU at periapsis and 0.0562 AU at apoapsis, driving measurable seasonal insolation cycles.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 1531 K (+1258°C / +2296°F) and receiving 546.90 S⊕ (~744,335 W/m²), TOI-3894 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star TOI-3894 is classified as a stellar host with an effective photospheric temperature of 5,990 K, a radius of 1.506 R☉, a mass of 1.089 M☉, an estimated bolometric luminosity of 2.62 L☉. Stellar evolution modeling indicates an estimated stellar age of 7.2 Gyr and a metallicity of [Fe/H] = 0.01 dex (near-solar heavy-element abundance). From Earth, TOI-3894 shines at apparent V-band magnitude 11.992 (faint and requiring research-grade or CCD telescopic photometry) in the Northern 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-3894 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 5,990 K |
| Stellar Radius | 1.5060 R☉ |
| Stellar Mass | 1.0890 M☉ |
| Bolometric Luminosity | 2.62 L☉ |
| Metallicity [Fe/H] | 0.010 dex |
| Stellar Age | 7.200 Gyr |
| Apparent Magnitude | V: 11.992 · G: 11.694 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.053540 AU |
| Orbital Period | 4.335 days |
| Mean Orbital Velocity | 134.4 km/s |
| Orbital Eccentricity (e) | 0.05000 |
| Orbital Inclination (i) | 84.6300° |
| Mean Bulk Density | 0.4 g/cm³ (46.2 km/s vesc) |
| Insolation Flux | 546.9030 S⊕ (~744,335 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 1361.300 LY (417.365 pc) |