K2-295 b
Astrophysical Synthesis & Habitability Characterization
K2-295 b is a confirmed gas giant exoplanet orbiting the star K2-295, located approximately 759.3 light-years (232.8 parsecs) from the Solar System. First announced in 2018 by K2 using the Transit detection technique (producing an estimated primary transit depth of 1.7339% across the stellar disk), this world measures 10.054 Earth radii (0.9 Jupiter radii) and has a measured mass of 106.473 Earth masses (0.33 Jupiter masses). Combining its mass and radius yields a mean bulk density of 0.58 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 1.05 g⊕ (10.3 m/s²), and an escape velocity of 36.4 km/s.
In its orbital architecture around K2-295, K2-295 b completes one full revolution every 4.025 Earth days at a semi-major axis of 0.0451 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 121.9 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 852 K (+579°C / +1074°F) and receiving 97.86 S⊕ (~133,187 W/m²), K2-295 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star K2-295 is classified as an orange K-type star of spectral type K5 V with an effective photospheric temperature of 4,444 K, a radius of 0.7 R☉, a mass of 0.74 M☉, an estimated bolometric luminosity of 0.171 L☉. Stellar evolution modeling indicates a metallicity of [Fe/H] = 0.14 dex (metal-rich relative to the Sun). From Earth, K2-295 shines at apparent V-band magnitude 13.894 (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 | K2-295 |
| Spectral Type | K5 V |
| Effective Temp (Teff) | 4,444 K |
| Stellar Radius | 0.7000 R☉ |
| Stellar Mass | 0.7400 M☉ |
| Bolometric Luminosity | 0.171 L☉ |
| Metallicity [Fe/H] | 0.140 dex |
| Stellar Age | — |
| Apparent Magnitude | V: 13.894 · G: 13.518 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.045100 AU |
| Orbital Period | 4.025 days |
| Mean Orbital Velocity | 121.9 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 89.3000° |
| Mean Bulk Density | 0.58 g/cm³ (36.4 km/s vesc) |
| Insolation Flux | 97.8595 S⊕ (~133,187 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 759.300 LY (232.801 pc) |