WASP-53 b
Astrophysical Synthesis & Habitability Characterization
WASP-53 b is a confirmed gas giant exoplanet orbiting the star WASP-53, located approximately 656.7 light-years (201.34 parsecs) from the Solar System. First announced in 2017 by Multiple Facilities using the Transit detection technique (producing an estimated primary transit depth of 1.9127% across the stellar disk), this world measures 12.038 Earth radii (1.07 Jupiter radii) and has a measured mass of 677.614 Earth masses (2.13 Jupiter masses). Combining its mass and radius yields a mean bulk density of 2.14 g/cm³ (an intermediate density indicative of a deep water-ice mantle or dense volatile envelope), a surface gravity of 4.68 g⊕ (45.9 m/s²), and an escape velocity of 83.9 km/s.
In its orbital architecture around WASP-53, WASP-53 b completes one full revolution every 3.31 Earth days at a semi-major axis of 0.04101 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 134.8 km/s (compared to Earth's 29.8 km/s). With a near-circular eccentricity of e = 0.03 (ranging from 0.0398 AU at periapsis to 0.0422 AU at apoapsis), the planet experiences minimal orbital distance variation.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 1053 K (+780°C / +1436°F) and receiving 241.67 S⊕ (~328,907 W/m²), WASP-53 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star WASP-53 is classified as a stellar host with an effective photospheric temperature of 4,953 K, a radius of 0.798 R☉, a mass of 0.839 M☉, an estimated bolometric luminosity of 0.344 L☉. Stellar evolution modeling indicates a metallicity of [Fe/H] = 0.22 dex (metal-rich relative to the Sun). From Earth, WASP-53 shines at apparent V-band magnitude 12.591 (faint and requiring research-grade or CCD telescopic photometry) in the Southern celestial hemisphere. The WASP-53 system is a multi-planet architecture hosting 2 confirmed worlds, with WASP-53 b sharing its stellar neighborhood alongside WASP-53 c.
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: Multiple Facilities · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | WASP-53 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 4,953 K |
| Stellar Radius | 0.7980 R☉ |
| Stellar Mass | 0.8390 M☉ |
| Bolometric Luminosity | 0.344 L☉ |
| Metallicity [Fe/H] | 0.220 dex |
| Stellar Age | — |
| Apparent Magnitude | V: 12.591 · G: 12.347 |
| System Architecture | 1 Star, 2 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.041010 AU |
| Orbital Period | 3.31 days |
| Mean Orbital Velocity | 134.8 km/s |
| Orbital Eccentricity (e) | 0.03000 |
| Orbital Inclination (i) | 87.0800° |
| Mean Bulk Density | 2.14 g/cm³ (83.9 km/s vesc) |
| Insolation Flux | 241.6656 S⊕ (~328,907 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 656.700 LY (201.338 pc) |