TOI-2040 b
Astrophysical Synthesis & Habitability Characterization
TOI-2040 b is a confirmed gas giant exoplanet orbiting the star TOI-2040, located approximately 472 light-years (144.72 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 1.1834% across the stellar disk), this world measures 10.323 Earth radii (0.92 Jupiter radii) and has a measured mass of 248.224 Earth masses (0.78 Jupiter masses). Combining its mass and radius yields a mean bulk density of 1.24 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 2.33 g⊕ (22.85 m/s²), and an escape velocity of 54.9 km/s.
In its orbital architecture around TOI-2040, TOI-2040 b completes one full revolution every 3.861 Earth days at a semi-major axis of 0.0473 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 133.3 km/s (compared to Earth's 29.8 km/s). Its moderate orbital eccentricity of e = 0.109 carries the world between 0.0421 AU at periapsis and 0.0525 AU at apoapsis, driving measurable seasonal insolation cycles.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 1070 K (+797°C / +1467°F) and receiving 216.00 S⊕ (~293,976 W/m²), TOI-2040 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star TOI-2040 is classified as a stellar host with an effective photospheric temperature of 5,132 K, a radius of 0.87 R☉, a mass of 0.92 M☉, an estimated bolometric luminosity of 0.471 L☉. Stellar evolution modeling indicates an estimated stellar age of 8.7 Gyr and a metallicity of [Fe/H] = 0.3 dex (metal-rich relative to the Sun). From Earth, TOI-2040 shines at apparent V-band magnitude 11.489 (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-2040 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 5,132 K |
| Stellar Radius | 0.8700 R☉ |
| Stellar Mass | 0.9200 M☉ |
| Bolometric Luminosity | 0.471 L☉ |
| Metallicity [Fe/H] | 0.300 dex |
| Stellar Age | 8.700 Gyr |
| Apparent Magnitude | V: 11.489 · G: 11.417 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.047300 AU |
| Orbital Period | 3.861 days |
| Mean Orbital Velocity | 133.3 km/s |
| Orbital Eccentricity (e) | 0.10900 |
| Orbital Inclination (i) | 88.4800° |
| Mean Bulk Density | 1.24 g/cm³ (54.9 km/s vesc) |
| Insolation Flux | 216.0000 S⊕ (~293,976 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 472.000 LY (144.717 pc) |