TOI-5340 b
Astrophysical Synthesis & Habitability Characterization
TOI-5340 b is a confirmed gas giant exoplanet orbiting the star TOI-5340, located approximately 1737.2 light-years (532.63 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 0.563% across the stellar disk), this world measures 15.076 Earth radii (1.34 Jupiter radii) and has a measured mass of 270.154 Earth masses (0.85 Jupiter masses). Combining its mass and radius yields a mean bulk density of 0.43 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 1.19 g⊕ (11.67 m/s²), and an escape velocity of 47.4 km/s.
In its orbital architecture around TOI-5340, TOI-5340 b completes one full revolution every 4.939 Earth days at a semi-major axis of 0.0628 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 138.3 km/s (compared to Earth's 29.8 km/s). Its moderate orbital eccentricity of e = 0.13 carries the world between 0.0546 AU at periapsis and 0.071 AU at apoapsis, driving measurable seasonal insolation cycles.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 1566 K (+1293°C / +2359°F) and receiving 1,004.00 S⊕ (~1,366,444 W/m²), TOI-5340 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star TOI-5340 is classified as a stellar host with an effective photospheric temperature of 5,990 K, a radius of 1.842 R☉, a mass of 1.35 M☉, an estimated bolometric luminosity of 3.919 L☉. Stellar evolution modeling indicates an estimated stellar age of 3.5 Gyr and a metallicity of [Fe/H] = 0.208 dex (metal-rich relative to the Sun). From Earth, TOI-5340 shines at apparent V-band magnitude 12.399 (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-5340 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 5,990 K |
| Stellar Radius | 1.8420 R☉ |
| Stellar Mass | 1.3500 M☉ |
| Bolometric Luminosity | 3.919 L☉ |
| Metallicity [Fe/H] | 0.208 dex |
| Stellar Age | 3.500 Gyr |
| Apparent Magnitude | V: 12.399 · G: 12.207 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.062800 AU |
| Orbital Period | 4.939 days |
| Mean Orbital Velocity | 138.3 km/s |
| Orbital Eccentricity (e) | 0.13000 |
| Orbital Inclination (i) | 86.1700° |
| Mean Bulk Density | 0.43 g/cm³ (47.4 km/s vesc) |
| Insolation Flux | 1004.0000 S⊕ (~1,366,444 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 1737.200 LY (532.629 pc) |