TOI-5349 b
Astrophysical Synthesis & Habitability Characterization
TOI-5349 b is a confirmed gas giant exoplanet orbiting the star TOI-5349, located approximately 614.3 light-years (188.34 parsecs) from the Solar System. First announced in 2026 by Transiting Exoplanet Survey Satellite (TESS) using the Transit detection technique (producing an estimated primary transit depth of 2.5995% across the stellar disk), this world measures 10.2 Earth radii (0.91 Jupiter radii) and has a measured mass of 127.4 Earth masses (0.4 Jupiter masses). Combining its mass and radius yields a mean bulk density of 0.66 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 1.22 g⊕ (11.96 m/s²), and an escape velocity of 39.5 km/s.
In its orbital architecture around TOI-5349, TOI-5349 b completes one full revolution every 3.318 Earth days at a semi-major axis of 0.0369 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 121 km/s (compared to Earth's 29.8 km/s). With a near-circular eccentricity of e = 0.03 (ranging from 0.0358 AU at periapsis to 0.038 AU at apoapsis), the planet experiences minimal orbital distance variation.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 719 K (+446°C / +835°F) and receiving 44.50 S⊕ (~60,565 W/m²), TOI-5349 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star TOI-5349 is classified as a low-mass red dwarf of spectral type M1+/-0.5 with an effective photospheric temperature of 3,751 K, a radius of 0.58 R☉, a mass of 0.61 M☉, an estimated bolometric luminosity of 0.06 L☉. Stellar evolution modeling indicates an estimated stellar age of 9 Gyr and a metallicity of [Fe/H] = 0.5 dex (metal-rich relative to the Sun). From Earth, TOI-5349 shines at apparent V-band magnitude 15.685 (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-5349 |
| Spectral Type | M1+/-0.5 |
| Effective Temp (Teff) | 3,751 K |
| Stellar Radius | 0.5800 R☉ |
| Stellar Mass | 0.6100 M☉ |
| Bolometric Luminosity | 0.06 L☉ |
| Metallicity [Fe/H] | 0.500 dex |
| Stellar Age | 9.000 Gyr |
| Apparent Magnitude | V: 15.685 · G: 14.891 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.036900 AU |
| Orbital Period | 3.318 days |
| Mean Orbital Velocity | 121 km/s |
| Orbital Eccentricity (e) | 0.03000 |
| Orbital Inclination (i) | 87.9000° |
| Mean Bulk Density | 0.66 g/cm³ (39.5 km/s vesc) |
| Insolation Flux | 44.5000 S⊕ (~60,565 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 614.300 LY (188.336 pc) |