K2-395 b
Astrophysical Synthesis & Habitability Characterization
K2-395 b is a confirmed sub-neptune exoplanet orbiting the star K2-395, located approximately 935.2 light-years (286.73 parsecs) from the Solar System. First announced in 2022 by K2 using the Transit detection technique (producing an estimated primary transit depth of 0.0925% across the stellar disk), this world measures 2.597 Earth radii and has a measured mass of 7.26 Earth masses. Combining its mass and radius yields a mean bulk density of 2.29 g/cm³ (an intermediate density indicative of a deep water-ice mantle or dense volatile envelope), a surface gravity of 1.08 g⊕ (10.59 m/s²), and an escape velocity of 18.7 km/s.
In its orbital architecture around K2-395, K2-395 b completes one full revolution every 4.803 Earth days.
☁️ Atmospheric Regime (Volatile / Gas Envelope): With a radius of 2.597 R⊕, K2-395 b exceeds the empirical ~1.8–2.2 R⊕ Fulton radius valley threshold, indicating a substantial hydrogen-helium or supercritical volatile envelope without a conventional solid terrestrial surface.
The host star K2-395 is classified as an orange K-type star of spectral type K0 with an effective photospheric temperature of 5,007 K, a radius of 0.783 R☉, a mass of 0.952 M☉, an estimated bolometric luminosity of 0.346 L☉. Stellar evolution modeling indicates a metallicity of [Fe/H] = -0.033 dex (near-solar heavy-element abundance). From Earth, K2-395 shines at apparent V-band magnitude 15.131 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere. The K2-395 system is a multi-planet architecture hosting 2 confirmed worlds, with K2-395 b sharing its stellar neighborhood alongside K2-395 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: K2 · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | K2-395 |
| Spectral Type | K0 |
| Effective Temp (Teff) | 5,007 K |
| Stellar Radius | 0.7830 R☉ |
| Stellar Mass | 0.9520 M☉ |
| Bolometric Luminosity | 0.346 L☉ |
| Metallicity [Fe/H] | -0.033 dex |
| Stellar Age | — |
| Apparent Magnitude | V: 15.131 · G: 14.156 |
| System Architecture | 1 Star, 2 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | — |
| Orbital Period | 4.803 days |
| Orbital Eccentricity (e) | Circular (0.00) |
| Orbital Inclination (i) | — |
| Mean Bulk Density | 2.29 g/cm³ (18.7 km/s vesc) |
| Insolation Flux | — |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 935.200 LY (286.727 pc) |