WASP-29 b
Astrophysical Synthesis & Habitability Characterization
WASP-29 b is a confirmed gas giant exoplanet orbiting the star WASP-29, located approximately 285.7 light-years (87.6 parsecs) from the Solar System. First announced in 2010 by SuperWASP using the Transit detection technique (producing an estimated primary transit depth of 1.0033% across the stellar disk), this world measures 8.631 Earth radii (0.77 Jupiter radii) and has a measured mass of 73.101 Earth masses (0.23 Jupiter masses). Combining its mass and radius yields a mean bulk density of 0.63 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 0.98 g⊕ (9.61 m/s²), and an escape velocity of 32.6 km/s.
In its orbital architecture around WASP-29, WASP-29 b completes one full revolution every 3.923 Earth days at a semi-major axis of 0.0457 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 126.7 km/s (compared to Earth's 29.8 km/s). With a near-circular eccentricity of e = 0.03 (ranging from 0.0443 AU at periapsis to 0.0471 AU at apoapsis), the planet experiences minimal orbital distance variation.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 970 K (+697°C / +1287°F) and receiving 121.77 S⊕ (~165,732 W/m²), WASP-29 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star WASP-29 is classified as a stellar host with an effective photospheric temperature of 4,800 K, a radius of 0.79 R☉, a mass of 0.77 M☉, an estimated bolometric luminosity of 0.297 L☉. Stellar evolution modeling indicates an estimated stellar age of 14 Gyr and a metallicity of [Fe/H] = 0.11 dex (metal-rich relative to the Sun). From Earth, WASP-29 shines at apparent V-band magnitude 11.331 (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: SuperWASP · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | WASP-29 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 4,800 K |
| Stellar Radius | 0.7900 R☉ |
| Stellar Mass | 0.7700 M☉ |
| Bolometric Luminosity | 0.297 L☉ |
| Metallicity [Fe/H] | 0.110 dex |
| Stellar Age | 14.000 Gyr |
| Apparent Magnitude | V: 11.331 · G: 10.893 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.045700 AU |
| Orbital Period | 3.923 days |
| Mean Orbital Velocity | 126.7 km/s |
| Orbital Eccentricity (e) | 0.03000 |
| Orbital Inclination (i) | 88.8000° |
| Mean Bulk Density | 0.63 g/cm³ (32.6 km/s vesc) |
| Insolation Flux | 121.7724 S⊕ (~165,732 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 285.700 LY (87.595 pc) |