TOI-3980 b
Astrophysical Synthesis & Habitability Characterization
TOI-3980 b is a confirmed gas giant exoplanet orbiting the star TOI-3980, located approximately 1587.5 light-years (486.72 parsecs) from the Solar System. First announced in 2025 by Transiting Exoplanet Survey Satellite (TESS) using the Transit detection technique (producing an estimated primary transit depth of 0.6647% across the stellar disk), this world measures 14.46 Earth radii (1.29 Jupiter radii) and has a measured mass of 187.519 Earth masses (0.59 Jupiter masses). Combining its mass and radius yields a mean bulk density of 0.34 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 0.9 g⊕ (8.83 m/s²), and an escape velocity of 40.3 km/s.
In its orbital architecture around TOI-3980, TOI-3980 b completes one full revolution every 3.609 Earth days at a semi-major axis of 0.0494 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 148.9 km/s (compared to Earth's 29.8 km/s). Its moderate orbital eccentricity of e = 0.16 carries the world between 0.0415 AU at periapsis and 0.0573 AU at apoapsis, driving measurable seasonal insolation cycles.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 1621 K (+1348°C / +2458°F) and receiving 1,153.00 S⊕ (~1,569,233 W/m²), TOI-3980 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star TOI-3980 is classified as a stellar host with an effective photospheric temperature of 5,840 K, a radius of 1.626 R☉, a mass of 1.24 M☉, an estimated bolometric luminosity of 2.759 L☉. Stellar evolution modeling indicates an estimated stellar age of 4.7 Gyr and a metallicity of [Fe/H] = 0.188 dex (metal-rich relative to the Sun). From Earth, TOI-3980 shines at apparent V-band magnitude 12.549 (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-3980 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 5,840 K |
| Stellar Radius | 1.6260 R☉ |
| Stellar Mass | 1.2400 M☉ |
| Bolometric Luminosity | 2.759 L☉ |
| Metallicity [Fe/H] | 0.188 dex |
| Stellar Age | 4.700 Gyr |
| Apparent Magnitude | V: 12.549 · G: 12.375 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.049400 AU |
| Orbital Period | 3.609 days |
| Mean Orbital Velocity | 148.9 km/s |
| Orbital Eccentricity (e) | 0.16000 |
| Orbital Inclination (i) | 81.9500° |
| Mean Bulk Density | 0.34 g/cm³ (40.3 km/s vesc) |
| Insolation Flux | 1153.0000 S⊕ (~1,569,233 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 1587.500 LY (486.721 pc) |