Kepler-1660 AB b
Astrophysical Synthesis & Habitability Characterization
Kepler-1660 AB b is a confirmed gas giant exoplanet orbiting the star Kepler-1660 A, located approximately 3876.5 light-years (1188.54 parsecs) from the Solar System. First announced in 2023 by Kepler using the Eclipse Timing Variations detection technique, this world measures 12.9 Earth radii (1.15 Jupiter radii) and has a measured mass of 1586.599 Earth masses (4.99 Jupiter masses). Combining its mass and radius yields a mean bulk density of 4.08 g/cm³ (a terrestrial silicate-iron composition comparable to Earth (5.51 g/cm³)), a surface gravity of 9.53 g⊕ (93.46 m/s²), and an escape velocity of 124.1 km/s.
In its orbital architecture around Kepler-1660 A, Kepler-1660 AB b completes one full revolution every 239.504 Earth days at a semi-major axis of 0.8 AU (comparable to the inner terrestrial zone between Venus, Earth at 1.00 AU, and Mars at 1.52 AU). Its mean orbital velocity is approximately 36.3 km/s (compared to Earth's 29.8 km/s). Its moderate orbital eccentricity of e = 0.05541 carries the world between 0.7557 AU at periapsis and 0.8443 AU at apoapsis, driving measurable seasonal insolation cycles.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 415 K (+142°C / +288°F) and receiving 7.28 S⊕ (~9,906 W/m²), Kepler-1660 AB b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star Kepler-1660 A is classified as a warm F-type star of spectral type F7 V with an effective photospheric temperature of 6,305 K, a radius of 1.491 R☉, a mass of 1.1366 M☉, an estimated bolometric luminosity of 3.152 L☉. Stellar evolution modeling indicates a metallicity of [Fe/H] = -0.36 dex (metal-poor relative to the Sun). From Earth, Kepler-1660 A shines at apparent V-band magnitude 13.595 (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-1660 A |
| Spectral Type | F7 V |
| Effective Temp (Teff) | 6,305 K |
| Stellar Radius | 1.4910 R☉ |
| Stellar Mass | 1.1366 M☉ |
| Bolometric Luminosity | 3.152 L☉ |
| Metallicity [Fe/H] | -0.360 dex |
| Stellar Age | — |
| Apparent Magnitude | V: 13.595 · G: 13.439 |
| System Architecture | 2 Stars, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.800000 AU |
| Orbital Period | 239.504 days |
| Mean Orbital Velocity | 36.3 km/s |
| Orbital Eccentricity (e) | 0.05541 |
| Orbital Inclination (i) | 86.3100° |
| Mean Bulk Density | 4.08 g/cm³ (124.1 km/s vesc) |
| Insolation Flux | 7.2787 S⊕ (~9,906 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 3876.500 LY (1188.540 pc) |