TOI-1420 b
Astrophysical Synthesis & Habitability Characterization
TOI-1420 b is a confirmed gas giant exoplanet orbiting the star TOI-1420, located approximately 658.6 light-years (201.92 parsecs) from the Solar System. First announced in 2023 by Transiting Exoplanet Survey Satellite (TESS) using the Transit detection technique (producing an estimated primary transit depth of 1.3948% across the stellar disk), this world measures 11.89 Earth radii (1.06 Jupiter radii) and has a measured mass of 25.1 Earth 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 0.18 g⊕ (1.77 m/s²), and an escape velocity of 16.3 km/s.
In its orbital architecture around TOI-1420, TOI-1420 b completes one full revolution every 6.956 Earth days at a semi-major axis of 0.071 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 111 km/s (compared to Earth's 29.8 km/s). Its moderate orbital eccentricity of e = 0.17 carries the world between 0.0589 AU at periapsis and 0.0831 AU at apoapsis, driving measurable seasonal insolation cycles.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 957 K (+684°C / +1263°F) and receiving 139.00 S⊕ (~189,179 W/m²), TOI-1420 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star TOI-1420 is classified as a stellar host with an effective photospheric temperature of 5,510 K, a radius of 0.923 R☉, a mass of 0.987 M☉, an estimated bolometric luminosity of 0.705 L☉. Stellar evolution modeling indicates an estimated stellar age of 10.7 Gyr and a metallicity of [Fe/H] = 0.28 dex (metal-rich relative to the Sun). From Earth, TOI-1420 shines at apparent V-band magnitude 11.655 (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-1420 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 5,510 K |
| Stellar Radius | 0.9230 R☉ |
| Stellar Mass | 0.9870 M☉ |
| Bolometric Luminosity | 0.705 L☉ |
| Metallicity [Fe/H] | 0.280 dex |
| Stellar Age | 10.700 Gyr |
| Apparent Magnitude | V: 11.655 · G: 11.738 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.071000 AU |
| Orbital Period | 6.956 days |
| Mean Orbital Velocity | 111 km/s |
| Orbital Eccentricity (e) | 0.17000 |
| Orbital Inclination (i) | 88.5800° |
| Mean Bulk Density | 0.08 g/cm³ (16.3 km/s vesc) |
| Insolation Flux | 139.0000 S⊕ (~189,179 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 658.600 LY (201.918 pc) |