TOI-3884 b
Astrophysical Synthesis & Habitability Characterization
TOI-3884 b is a confirmed gas giant exoplanet orbiting the star TOI-3884, located approximately 140.7 light-years (43.15 parsecs) from the Solar System. First announced in 2022 by Transiting Exoplanet Survey Satellite (TESS) using the Transit detection technique (producing an estimated primary transit depth of 3.8102% across the stellar disk), this world measures 6.43 Earth radii (0.57 Jupiter radii) and has a measured mass of 32.59 Earth masses (0.1 Jupiter masses). Combining its mass and radius yields a mean bulk density of 0.68 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 0.79 g⊕ (7.75 m/s²), and an escape velocity of 25.2 km/s.
In its orbital architecture around TOI-3884, TOI-3884 b completes one full revolution every 4.545 Earth days at a semi-major axis of 0.0361 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 86.4 km/s (compared to Earth's 29.8 km/s). Its moderate orbital eccentricity of e = 0.06 carries the world between 0.0339 AU at periapsis and 0.0383 AU at apoapsis, driving measurable seasonal insolation cycles.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 441 K (+168°C / +334°F) and receiving 6.29 S⊕ (~8,561 W/m²), TOI-3884 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star TOI-3884 is classified as a low-mass red dwarf of spectral type M4 with an effective photospheric temperature of 3,180 K, a radius of 0.302 R☉, a mass of 0.298 M☉, an estimated bolometric luminosity of 0.00837 L☉. Stellar evolution modeling indicates a metallicity of [Fe/H] = 0.04 dex (near-solar heavy-element abundance). From Earth, TOI-3884 shines at apparent V-band magnitude 15.744 (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-3884 |
| Spectral Type | M4 |
| Effective Temp (Teff) | 3,180 K |
| Stellar Radius | 0.3020 R☉ |
| Stellar Mass | 0.2980 M☉ |
| Bolometric Luminosity | 0.00837 L☉ |
| Metallicity [Fe/H] | 0.040 dex |
| Stellar Age | — |
| Apparent Magnitude | V: 15.744 · G: 14.275 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.036100 AU |
| Orbital Period | 4.545 days |
| Mean Orbital Velocity | 86.4 km/s |
| Orbital Eccentricity (e) | 0.06000 |
| Orbital Inclination (i) | 89.8100° |
| Mean Bulk Density | 0.68 g/cm³ (25.2 km/s vesc) |
| Insolation Flux | 6.2900 S⊕ (~8,561 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 140.700 LY (43.145 pc) |