TOI-6842 A b
Astrophysical Synthesis & Habitability Characterization
TOI-6842 A b is a confirmed gas giant exoplanet orbiting the star TOI-6842, located approximately 1303.9 light-years (399.77 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 1.4762% across the stellar disk), this world measures 18.461 Earth radii (1.65 Jupiter radii) and has a measured mass of 95.984 Earth masses (0.3 Jupiter masses). Combining its mass and radius yields a mean bulk density of 0.08 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 0.28 g⊕ (2.75 m/s²), and an escape velocity of 25.5 km/s.
In its orbital architecture around TOI-6842, TOI-6842 A b completes one full revolution every 5.392 Earth days at a semi-major axis of 0.06023 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 121.5 km/s (compared to Earth's 29.8 km/s). The orbit is modeled as circular (e = 0.00), maintaining a constant stellar distance throughout its year.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 1327 K (+1054°C / +1929°F) and receiving 534.39 S⊕ (~727,308 W/m²), TOI-6842 A b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star TOI-6842 is classified as a stellar host with an effective photospheric temperature of 5,725 K, a radius of 1.393 R☉, a mass of 1.002 M☉, an estimated bolometric luminosity of 1.87 L☉. Stellar evolution modeling indicates an estimated stellar age of 9.6 Gyr and a metallicity of [Fe/H] = -0.02 dex (near-solar heavy-element abundance). From Earth, TOI-6842 shines at apparent V-band magnitude 12.165 (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-6842 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 5,725 K |
| Stellar Radius | 1.3930 R☉ |
| Stellar Mass | 1.0020 M☉ |
| Bolometric Luminosity | 1.87 L☉ |
| Metallicity [Fe/H] | -0.020 dex |
| Stellar Age | 9.600 Gyr |
| Apparent Magnitude | V: 12.165 · G: 12.052 |
| System Architecture | 2 Stars, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.060230 AU |
| Orbital Period | 5.392 days |
| Mean Orbital Velocity | 121.5 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 86.6700° |
| Mean Bulk Density | 0.08 g/cm³ (25.5 km/s vesc) |
| Insolation Flux | 534.3924 S⊕ (~727,308 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 1303.900 LY (399.765 pc) |