Kepler-585 b
Astrophysical Synthesis & Habitability Characterization
Kepler-585 b is a confirmed sub-neptune exoplanet orbiting the star Kepler-585, located approximately 1908.6 light-years (585.19 parsecs) from the Solar System. First announced in 2016 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.0778% across the stellar disk), this world measures 2.83 Earth radii and has a measured mass of 8.4 Earth masses. Combining its mass and radius yields a mean bulk density of 2.04 g/cm³ (an intermediate density indicative of a deep water-ice mantle or dense volatile envelope), a surface gravity of 1.05 g⊕ (10.3 m/s²), and an escape velocity of 19.3 km/s.
In its orbital architecture around Kepler-585, Kepler-585 b completes one full revolution every 2.752 Earth days at a semi-major axis of 0.03841 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 151.8 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 1178 K (+905°C / +1661°F) and receiving 489.15 S⊕ (~665,732 W/m²), Kepler-585 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star Kepler-585 is classified as a stellar host with an effective photospheric temperature of 5,593 K, a radius of 0.93 R☉, a mass of 0.96 M☉, an estimated bolometric luminosity of 0.759 L☉. Stellar evolution modeling indicates an estimated stellar age of 3.63 Gyr and a metallicity of [Fe/H] = 0.03 dex (near-solar heavy-element abundance). From Earth, Kepler-585 shines at apparent V-band magnitude 14.188 (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-585 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 5,593 K |
| Stellar Radius | 0.9300 R☉ |
| Stellar Mass | 0.9600 M☉ |
| Bolometric Luminosity | 0.759 L☉ |
| Metallicity [Fe/H] | 0.030 dex |
| Stellar Age | 3.630 Gyr |
| Apparent Magnitude | V: 14.188 · G: 14.017 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.038410 AU |
| Orbital Period | 2.752 days |
| Mean Orbital Velocity | 151.8 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 87.3600° |
| Mean Bulk Density | 2.04 g/cm³ (19.3 km/s vesc) |
| Insolation Flux | 489.1490 S⊕ (~665,732 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 1908.600 LY (585.187 pc) |