TOI-564 b
Astrophysical Synthesis & Habitability Characterization
TOI-564 b is a confirmed gas giant exoplanet orbiting the star TOI-564, located approximately 650.9 light-years (199.58 parsecs) from the Solar System. First announced in 2020 by Transiting Exoplanet Survey Satellite (TESS) using the Transit detection technique (producing an estimated primary transit depth of 0.9281% across the stellar disk), this world measures 11.433 Earth radii (1.02 Jupiter radii) and has a measured mass of 464.985 Earth masses (1.46 Jupiter masses). Combining its mass and radius yields a mean bulk density of 1.72 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 3.56 g⊕ (34.91 m/s²), and an escape velocity of 71.3 km/s.
In its orbital architecture around TOI-564, TOI-564 b completes one full revolution every 1.651 Earth days at a semi-major axis of 0.02734 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 180.1 km/s (compared to Earth's 29.8 km/s). Its moderate orbital eccentricity of e = 0.072 carries the world between 0.0254 AU at periapsis and 0.0293 AU at apoapsis, driving measurable seasonal insolation cycles.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 1714 K (+1441°C / +2626°F) and receiving 1,423.00 S⊕ (~1,936,703 W/m²), TOI-564 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star TOI-564 is classified as a stellar host with an effective photospheric temperature of 5,640 K, a radius of 1.088 R☉, a mass of 0.998 M☉, an estimated bolometric luminosity of 1.075 L☉. Stellar evolution modeling indicates an estimated stellar age of 7.3 Gyr and a metallicity of [Fe/H] = 0.143 dex (metal-rich relative to the Sun). From Earth, TOI-564 shines at apparent V-band magnitude 11.097 (faint and requiring research-grade or CCD telescopic photometry) in the Southern 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-564 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 5,640 K |
| Stellar Radius | 1.0880 R☉ |
| Stellar Mass | 0.9980 M☉ |
| Bolometric Luminosity | 1.075 L☉ |
| Metallicity [Fe/H] | 0.143 dex |
| Stellar Age | 7.300 Gyr |
| Apparent Magnitude | V: 11.097 · G: 11.142 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.027340 AU |
| Orbital Period | 1.651 days |
| Mean Orbital Velocity | 180.1 km/s |
| Orbital Eccentricity (e) | 0.07200 |
| Orbital Inclination (i) | 78.3800° |
| Mean Bulk Density | 1.72 g/cm³ (71.3 km/s vesc) |
| Insolation Flux | 1423.0000 S⊕ (~1,936,703 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 650.900 LY (199.581 pc) |