WTS-2 b
Astrophysical Synthesis & Habitability Characterization
WTS-2 b is a confirmed gas giant exoplanet orbiting the star WTS-2, located approximately 3361.9 light-years (1030.77 parsecs) from the Solar System. First announced in 2014 by United Kingdom Infrared Telescope using the Transit detection technique (producing an estimated primary transit depth of 3.4693% across the stellar disk), this world measures 15.278 Earth radii (1.36 Jupiter radii) and has a measured mass of 355.97 Earth masses (1.12 Jupiter masses). Combining its mass and radius yields a mean bulk density of 0.55 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 1.53 g⊕ (15 m/s²), and an escape velocity of 54 km/s.
In its orbital architecture around WTS-2, WTS-2 b completes one full revolution every 1.019 Earth days at a semi-major axis of 0.01855 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 198.1 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 2000 K (+1727°C / +3141°F) and receiving 2,544.65 S⊕ (~3,463,270 W/m²), WTS-2 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star WTS-2 is classified as an orange K-type star of spectral type K2 V with an effective photospheric temperature of 5,000 K, a radius of 0.752 R☉, a mass of 0.82 M☉, an estimated bolometric luminosity of 0.317 L☉. Stellar evolution modeling indicates an estimated stellar age of 0.6 Gyr and a metallicity of [Fe/H] = 0.2 dex (metal-rich relative to the Sun). From Earth, WTS-2 shines at apparent V-band magnitude 15.954 (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: United Kingdom Infrared Telescope · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | WTS-2 |
| Spectral Type | K2 V |
| Effective Temp (Teff) | 5,000 K |
| Stellar Radius | 0.7520 R☉ |
| Stellar Mass | 0.8200 M☉ |
| Bolometric Luminosity | 0.317 L☉ |
| Metallicity [Fe/H] | 0.200 dex |
| Stellar Age | 0.600 Gyr |
| Apparent Magnitude | V: 15.954 · G: 15.597 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.018550 AU |
| Orbital Period | 1.019 days |
| Mean Orbital Velocity | 198.1 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 83.5500° |
| Mean Bulk Density | 0.55 g/cm³ (54 km/s vesc) |
| Insolation Flux | 2544.6509 S⊕ (~3,463,270 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 3361.900 LY (1030.768 pc) |