TOI-3757 b
Astrophysical Synthesis & Habitability Characterization
TOI-3757 b is a confirmed gas giant exoplanet orbiting the star TOI-3757, located approximately 590.8 light-years (181.14 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 3.1486% across the stellar disk), this world measures 12 Earth radii (1.07 Jupiter radii) and has a measured mass of 85.3 Earth masses (0.27 Jupiter masses). Combining its mass and radius yields a mean bulk density of 0.27 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 0.59 g⊕ (5.79 m/s²), and an escape velocity of 29.8 km/s.
In its orbital architecture around TOI-3757, TOI-3757 b completes one full revolution every 3.439 Earth days at a semi-major axis of 0.03845 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 121.6 km/s (compared to Earth's 29.8 km/s). Its moderate orbital eccentricity of e = 0.14 carries the world between 0.0331 AU at periapsis and 0.0438 AU at apoapsis, driving measurable seasonal insolation cycles.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 759 K (+486°C / +907°F) and receiving 55.40 S⊕ (~75,399 W/m²), TOI-3757 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star TOI-3757 is classified as a low-mass red dwarf of spectral type M0 V with an effective photospheric temperature of 3,913 K, a radius of 0.62 R☉, a mass of 0.64 M☉, an estimated bolometric luminosity of 0.081 L☉. Stellar evolution modeling indicates an estimated stellar age of 7.1 Gyr and a metallicity of [Fe/H] = 0 dex (near-solar heavy-element abundance). From Earth, TOI-3757 shines at apparent V-band magnitude 14.812 (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-3757 |
| Spectral Type | M0 V |
| Effective Temp (Teff) | 3,913 K |
| Stellar Radius | 0.6200 R☉ |
| Stellar Mass | 0.6400 M☉ |
| Bolometric Luminosity | 0.081 L☉ |
| Metallicity [Fe/H] | 0.000 dex |
| Stellar Age | 7.100 Gyr |
| Apparent Magnitude | V: 14.812 · G: 14.132 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.038450 AU |
| Orbital Period | 3.439 days |
| Mean Orbital Velocity | 121.6 km/s |
| Orbital Eccentricity (e) | 0.14000 |
| Orbital Inclination (i) | 86.7600° |
| Mean Bulk Density | 0.27 g/cm³ (29.8 km/s vesc) |
| Insolation Flux | 55.4000 S⊕ (~75,399 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 590.800 LY (181.139 pc) |