TOI-2019 b
Astrophysical Synthesis & Habitability Characterization
TOI-2019 b is a confirmed sub-neptune exoplanet orbiting the star TOI-2019, located approximately 645.8 light-years (198.01 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 0.0784% across the stellar disk), this world measures 5.333 Earth radii (0.48 Jupiter radii) and has a measured mass of 34.4 Earth masses (0.11 Jupiter masses). Combining its mass and radius yields a mean bulk density of 1.25 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 1.21 g⊕ (11.87 m/s²), and an escape velocity of 28.4 km/s.
In its orbital architecture around TOI-2019, TOI-2019 b completes one full revolution every 15.344 Earth days at a semi-major axis of 0.128 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 90.8 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 917 K (+644°C / +1191°F) and receiving 126.05 S⊕ (~171,557 W/m²), TOI-2019 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star TOI-2019 is classified as a stellar host with an effective photospheric temperature of 5,626 K, a radius of 1.7457 R☉, a mass of 1.1832 M☉, an estimated bolometric luminosity of 2.739 L☉. Stellar evolution modeling indicates an estimated stellar age of 6.4 Gyr and a metallicity of [Fe/H] = 0.409 dex (metal-rich relative to the Sun). From Earth, TOI-2019 shines at apparent V-band magnitude 10.263 (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-2019 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 5,626 K |
| Stellar Radius | 1.7457 R☉ |
| Stellar Mass | 1.1832 M☉ |
| Bolometric Luminosity | 2.739 L☉ |
| Metallicity [Fe/H] | 0.409 dex |
| Stellar Age | 6.400 Gyr |
| Apparent Magnitude | V: 10.263 · G: 10.077 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.128000 AU |
| Orbital Period | 15.344 days |
| Mean Orbital Velocity | 90.8 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | — |
| Mean Bulk Density | 1.25 g/cm³ (28.4 km/s vesc) |
| Insolation Flux | 126.0520 S⊕ (~171,557 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 645.800 LY (198.007 pc) |