K2-260 b
Astrophysical Synthesis & Habitability Characterization
K2-260 b is a confirmed gas giant exoplanet orbiting the star K2-260, located approximately 2165.1 light-years (663.83 parsecs) from the Solar System. First announced in 2018 by K2 using the Transit detection technique (producing an estimated primary transit depth of 0.9255% across the stellar disk), this world measures 18.416 Earth radii (1.64 Jupiter radii) and has a measured mass of 546.665 Earth masses (1.72 Jupiter masses). Combining its mass and radius yields a mean bulk density of 0.48 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 1.61 g⊕ (15.79 m/s²), and an escape velocity of 60.9 km/s.
In its orbital architecture around K2-260, K2-260 b completes one full revolution every 2.627 Earth days at a semi-major axis of 0.04392 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 181.9 km/s (compared to Earth's 29.8 km/s). Its moderate orbital eccentricity of e = 0.053 carries the world between 0.0416 AU at periapsis and 0.0462 AU at apoapsis, driving measurable seasonal insolation cycles.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 2090 K (+1817°C / +3303°F) and receiving 2,520.03 S⊕ (~3,429,761 W/m²), K2-260 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star K2-260 is classified as a warm F-type star of spectral type F6 V with an effective photospheric temperature of 6,860 K, a radius of 1.755 R☉, a mass of 1.637 M☉, an estimated bolometric luminosity of 6.12 L☉. Stellar evolution modeling indicates an estimated stellar age of 0.65 Gyr and a metallicity of [Fe/H] = 0.334 dex (metal-rich relative to the Sun). From Earth, K2-260 shines at apparent V-band magnitude 12.624 (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: K2 · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | K2-260 |
| Spectral Type | F6 V |
| Effective Temp (Teff) | 6,860 K |
| Stellar Radius | 1.7550 R☉ |
| Stellar Mass | 1.6370 M☉ |
| Bolometric Luminosity | 6.12 L☉ |
| Metallicity [Fe/H] | 0.334 dex |
| Stellar Age | 0.650 Gyr |
| Apparent Magnitude | V: 12.624 · G: 12.467 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.043920 AU |
| Orbital Period | 2.627 days |
| Mean Orbital Velocity | 181.9 km/s |
| Orbital Eccentricity (e) | 0.05300 |
| Orbital Inclination (i) | 89.1800° |
| Mean Bulk Density | 0.48 g/cm³ (60.9 km/s vesc) |
| Insolation Flux | 2520.0300 S⊕ (~3,429,761 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 2165.100 LY (663.834 pc) |