TIC 198190129 b
Astrophysical Synthesis & Habitability Characterization
TIC 198190129 b is a confirmed sub-neptune exoplanet orbiting the star TIC 198190129, located approximately 424.1 light-years (130.04 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 0.1749% across the stellar disk), this world measures 2.923 Earth radii and has a measured mass of 8.87 Earth masses. Combining its mass and radius yields a mean bulk density of 1.96 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 1.04 g⊕ (10.2 m/s²), and an escape velocity of 19.5 km/s.
In its orbital architecture around TIC 198190129, TIC 198190129 b completes one full revolution every 7.948 Earth days.
☁️ Atmospheric Regime (Volatile / Gas Envelope): With a radius of 2.923 R⊕, TIC 198190129 b exceeds the empirical ~1.8–2.2 R⊕ Fulton radius valley threshold, indicating a substantial hydrogen-helium or supercritical volatile envelope without a conventional solid terrestrial surface.
The host star TIC 198190129 is classified as a stellar host with an effective photospheric temperature of 4,378 K, a radius of 0.6407 R☉, a mass of 0.638 M☉, an estimated bolometric luminosity of 0.135 L☉. From Earth, TIC 198190129 shines at apparent V-band magnitude 13.704 (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 | TIC 198190129 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 4,378 K |
| Stellar Radius | 0.6407 R☉ |
| Stellar Mass | 0.6380 M☉ |
| Bolometric Luminosity | 0.135 L☉ |
| Metallicity [Fe/H] | — |
| Stellar Age | — |
| Apparent Magnitude | V: 13.704 · G: 13.253 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | — |
| Orbital Period | 7.948 days |
| Orbital Eccentricity (e) | Circular (0.00) |
| Orbital Inclination (i) | 88.9679° |
| Mean Bulk Density | 1.96 g/cm³ (19.5 km/s vesc) |
| Insolation Flux | — |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 424.100 LY (130.035 pc) |