Qatar-6 b
Astrophysical Synthesis & Habitability Characterization
Qatar-6 b is a confirmed gas giant exoplanet orbiting the star Qatar-6, located approximately 328.9 light-years (100.85 parsecs) from the Solar System. First announced in 2017 by Qatar using the Transit detection technique (producing an estimated primary transit depth of 2.2848% across the stellar disk), this world measures 11.904 Earth radii (1.06 Jupiter radii) and has a measured mass of 212.31 Earth masses (0.67 Jupiter masses). Combining its mass and radius yields a mean bulk density of 0.69 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 1.5 g⊕ (14.71 m/s²), and an escape velocity of 47.2 km/s.
In its orbital architecture around Qatar-6, Qatar-6 b completes one full revolution every 3.506 Earth days at a semi-major axis of 0.0423 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 131.2 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 1006 K (+733°C / +1351°F) and receiving 174.90 S⊕ (~238,041 W/m²), Qatar-6 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star Qatar-6 is classified as an orange K-type star of spectral type K2 V with an effective photospheric temperature of 5,052 K, a radius of 0.722 R☉, a mass of 0.822 M☉, an estimated bolometric luminosity of 0.305 L☉. Stellar evolution modeling indicates an estimated stellar age of 1.02 Gyr and a metallicity of [Fe/H] = -0.025 dex (near-solar heavy-element abundance). From Earth, Qatar-6 shines at apparent V-band magnitude 11.496 (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: Qatar · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | Qatar-6 |
| Spectral Type | K2 V |
| Effective Temp (Teff) | 5,052 K |
| Stellar Radius | 0.7220 R☉ |
| Stellar Mass | 0.8220 M☉ |
| Bolometric Luminosity | 0.305 L☉ |
| Metallicity [Fe/H] | -0.025 dex |
| Stellar Age | 1.020 Gyr |
| Apparent Magnitude | V: 11.496 · G: 11.125 |
| System Architecture | 2 Stars, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.042300 AU |
| Orbital Period | 3.506 days |
| Mean Orbital Velocity | 131.2 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 86.0100° |
| Mean Bulk Density | 0.69 g/cm³ (47.2 km/s vesc) |
| Insolation Flux | 174.9015 S⊕ (~238,041 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 328.900 LY (100.848 pc) |