TOI-1798.02
Astrophysical Synthesis & Habitability Characterization
TOI-1798.02 is a confirmed super-earth exoplanet orbiting the star TOI-1798, located approximately 369.1 light-years (113.18 parsecs) from the Solar System. First announced in 2024 by Transiting Exoplanet Survey Satellite (TESS) using the Transit detection technique (producing an estimated primary transit depth of 0.0296% across the stellar disk), this world measures 1.464 Earth radii and has a measured mass of 5.6 Earth masses. Combining its mass and radius yields a mean bulk density of 9.84 g/cm³ (an iron-enriched, high-compression rocky core), a surface gravity of 2.61 g⊕ (25.6 m/s²), and an escape velocity of 21.9 km/s.
In its orbital architecture around TOI-1798, TOI-1798.02 completes one full revolution every 0.438 Earth days at a semi-major axis of 0.010789 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 268.1 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 1936 K (+1663°C / +3025°F) and receiving 3,345.44 S⊕ (~4,553,144 W/m²), TOI-1798.02 orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star TOI-1798 is classified as a stellar host with an effective photospheric temperature of 5,165 K, a radius of 0.78 R☉, a mass of 0.87 M☉, an estimated bolometric luminosity of 0.388 L☉. Stellar evolution modeling indicates an estimated stellar age of 2.6 Gyr and a metallicity of [Fe/H] = 0.073 dex (metal-rich relative to the Sun). From Earth, TOI-1798 shines at apparent V-band magnitude 11.361 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere. The TOI-1798 system is a multi-planet architecture hosting 2 confirmed worlds, with TOI-1798.02 sharing its stellar neighborhood alongside TOI-1798.01.
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-1798 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 5,165 K |
| Stellar Radius | 0.7800 R☉ |
| Stellar Mass | 0.8700 M☉ |
| Bolometric Luminosity | 0.388 L☉ |
| Metallicity [Fe/H] | 0.073 dex |
| Stellar Age | 2.600 Gyr |
| Apparent Magnitude | V: 11.361 · G: 11.067 |
| System Architecture | 1 Star, 2 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.010789 AU |
| Orbital Period | 0.438 days |
| Mean Orbital Velocity | 268.1 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | — |
| Mean Bulk Density | 9.84 g/cm³ (21.9 km/s vesc) |
| Insolation Flux | 3345.4400 S⊕ (~4,553,144 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 369.100 LY (113.181 pc) |