Wendelstein-1 b
Astrophysical Synthesis & Habitability Characterization
Wendelstein-1 b is a confirmed gas giant exoplanet orbiting the star Wendelstein-1, located approximately 995.8 light-years (305.3 parsecs) from the Solar System. First announced in 2020 by Haleakala Observatory using the Transit detection technique (producing an estimated primary transit depth of 3.0191% across the stellar disk), this world measures 11.561 Earth radii (1.03 Jupiter radii) and has a measured mass of 188.155 Earth masses (0.59 Jupiter masses). Combining its mass and radius yields a mean bulk density of 0.67 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 1.41 g⊕ (13.83 m/s²), and an escape velocity of 45.1 km/s.
In its orbital architecture around Wendelstein-1, Wendelstein-1 b completes one full revolution every 2.663 Earth days at a semi-major axis of 0.0282 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 115.2 km/s (compared to Earth's 29.8 km/s). With a near-circular eccentricity of e = 0.012 (ranging from 0.0279 AU at periapsis to 0.0285 AU at apoapsis), the planet experiences minimal orbital distance variation.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 2198 K (+1925°C / +3497°F) and receiving 113.61 S⊕ (~154,629 W/m²), Wendelstein-1 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star Wendelstein-1 is classified as an orange K-type star of spectral type K7 V with an effective photospheric temperature of 4,251 K, a radius of 0.61 R☉, a mass of 0.65 M☉, an estimated bolometric luminosity of 0.109 L☉. From Earth, Wendelstein-1 shines at apparent V-band magnitude 15.564 (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: Haleakala Observatory · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | Wendelstein-1 |
| Spectral Type | K7 V |
| Effective Temp (Teff) | 4,251 K |
| Stellar Radius | 0.6100 R☉ |
| Stellar Mass | 0.6500 M☉ |
| Bolometric Luminosity | 0.109 L☉ |
| Metallicity [Fe/H] | — |
| Stellar Age | — |
| Apparent Magnitude | V: 15.564 · G: 15.032 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.028200 AU |
| Orbital Period | 2.663 days |
| Mean Orbital Velocity | 115.2 km/s |
| Orbital Eccentricity (e) | 0.01200 |
| Orbital Inclination (i) | 86.1200° |
| Mean Bulk Density | 0.67 g/cm³ (45.1 km/s vesc) |
| Insolation Flux | 113.6142 S⊕ (~154,629 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 995.800 LY (305.300 pc) |