Kepler-880 b
Astrophysical Synthesis & Habitability Characterization
Kepler-880 b is a confirmed sub-neptune exoplanet orbiting the star Kepler-880, located approximately 1961.3 light-years (601.32 parsecs) from the Solar System. First announced in 2016 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.0196% across the stellar disk), this world measures 2.66 Earth radii and has a measured mass of 7.56 Earth masses. Combining its mass and radius yields a mean bulk density of 2.21 g/cm³ (an intermediate density indicative of a deep water-ice mantle or dense volatile envelope), a surface gravity of 1.07 g⊕ (10.49 m/s²), and an escape velocity of 18.9 km/s.
In its orbital architecture around Kepler-880, Kepler-880 b completes one full revolution every 7.715 Earth days at a semi-major axis of 0.0915 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 129 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 1622 K (+1349°C / +2460°F) and receiving 586.17 S⊕ (~797,776 W/m²), Kepler-880 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star Kepler-880 is classified as a stellar host with an effective photospheric temperature of 6,761 K, a radius of 1.74 R☉, a mass of 1.46 M☉, an estimated bolometric luminosity of 5.676 L☉. Stellar evolution modeling indicates an estimated stellar age of 1.66 Gyr and a metallicity of [Fe/H] = 0.03 dex (near-solar heavy-element abundance). From Earth, Kepler-880 shines at apparent V-band magnitude 11.845 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere. The Kepler-880 system is a multi-planet architecture hosting 2 confirmed worlds, with Kepler-880 b sharing its stellar neighborhood alongside Kepler-880 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: Kepler · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | Kepler-880 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 6,761 K |
| Stellar Radius | 1.7400 R☉ |
| Stellar Mass | 1.4600 M☉ |
| Bolometric Luminosity | 5.676 L☉ |
| Metallicity [Fe/H] | 0.030 dex |
| Stellar Age | 1.660 Gyr |
| Apparent Magnitude | V: 11.845 · G: 11.964 |
| System Architecture | 1 Star, 2 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.091500 AU |
| Orbital Period | 7.715 days |
| Mean Orbital Velocity | 129 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 81.5900° |
| Mean Bulk Density | 2.21 g/cm³ (18.9 km/s vesc) |
| Insolation Flux | 586.1690 S⊕ (~797,776 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 1961.300 LY (601.324 pc) |