TOI-5301 b
Astrophysical Synthesis & Habitability Characterization
TOI-5301 b is a confirmed gas giant exoplanet orbiting the star TOI-5301, located approximately 2052 light-years (629.16 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 0.3031% across the stellar disk), this world measures 13.092 Earth radii (1.17 Jupiter radii) and has a measured mass of 1182.322 Earth masses (3.72 Jupiter masses). Combining its mass and radius yields a mean bulk density of 2.91 g/cm³ (an intermediate density indicative of a deep water-ice mantle or dense volatile envelope), a surface gravity of 6.9 g⊕ (67.67 m/s²), and an escape velocity of 106.3 km/s.
In its orbital architecture around TOI-5301, TOI-5301 b completes one full revolution every 5.859 Earth days at a semi-major axis of 0.073 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 135.6 km/s (compared to Earth's 29.8 km/s). The planet follows a highly eccentric trajectory (e = 0.33, swinging from 0.0489 AU at periapsis out to 0.0971 AU at apoapsis), pointing to past dynamical scattering or secular gravitational perturbations.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 1648 K (+1375°C / +2507°F) and receiving 429.79 S⊕ (~584,950 W/m²), TOI-5301 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star TOI-5301 is classified as a stellar host with an effective photospheric temperature of 6,260 K, a radius of 2.18 R☉, a mass of 1.507 M☉, an estimated bolometric luminosity of 6.548 L☉. Stellar evolution modeling indicates an estimated stellar age of 2.29 Gyr and a metallicity of [Fe/H] = 0.05 dex (near-solar heavy-element abundance). From Earth, TOI-5301 shines at apparent V-band magnitude 11.738 (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-5301 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 6,260 K |
| Stellar Radius | 2.1800 R☉ |
| Stellar Mass | 1.5070 M☉ |
| Bolometric Luminosity | 6.548 L☉ |
| Metallicity [Fe/H] | 0.050 dex |
| Stellar Age | 2.290 Gyr |
| Apparent Magnitude | V: 11.738 · G: 11.570 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.073000 AU |
| Orbital Period | 5.859 days |
| Mean Orbital Velocity | 135.6 km/s |
| Orbital Eccentricity (e) | 0.33000 |
| Orbital Inclination (i) | 83.3000° |
| Mean Bulk Density | 2.91 g/cm³ (106.3 km/s vesc) |
| Insolation Flux | 429.7940 S⊕ (~584,950 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 2052.000 LY (629.161 pc) |