Kepler-472 b
Astrophysical Synthesis & Habitability Characterization
Kepler-472 b is a confirmed sub-neptune exoplanet orbiting the star Kepler-472, located approximately 1000 light-years (306.6 parsecs) from the Solar System. First announced in 2016 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.1432% across the stellar disk), this world measures 3.22 Earth radii (0.29 Jupiter radii) and has a measured mass of 10.5 Earth masses. Combining its mass and radius yields a mean bulk density of 1.73 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 1.01 g⊕ (9.9 m/s²), and an escape velocity of 20.2 km/s.
In its orbital architecture around Kepler-472, Kepler-472 b completes one full revolution every 4.176 Earth days at a semi-major axis of 0.04823 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 125.6 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 876 K (+603°C / +1117°F) and receiving 139.24 S⊕ (~189,500 W/m²), Kepler-472 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star Kepler-472 is classified as a stellar host with an effective photospheric temperature of 4,996 K, a radius of 0.78 R☉, a mass of 0.85 M☉, an estimated bolometric luminosity of 0.34 L☉. Stellar evolution modeling indicates an estimated stellar age of 2.69 Gyr and a metallicity of [Fe/H] = 0.16 dex (metal-rich relative to the Sun). From Earth, Kepler-472 shines at apparent V-band magnitude 13.898 (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: Kepler · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | Kepler-472 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 4,996 K |
| Stellar Radius | 0.7800 R☉ |
| Stellar Mass | 0.8500 M☉ |
| Bolometric Luminosity | 0.34 L☉ |
| Metallicity [Fe/H] | 0.160 dex |
| Stellar Age | 2.690 Gyr |
| Apparent Magnitude | V: 13.898 · G: 13.670 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.048230 AU |
| Orbital Period | 4.176 days |
| Mean Orbital Velocity | 125.6 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 83.7500° |
| Mean Bulk Density | 1.73 g/cm³ (20.2 km/s vesc) |
| Insolation Flux | 139.2360 S⊕ (~189,500 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 1000.000 LY (306.602 pc) |