K2-342 b
Astrophysical Synthesis & Habitability Characterization
K2-342 b is a confirmed sub-neptune exoplanet orbiting the star K2-342, located approximately 679.6 light-years (208.36 parsecs) from the Solar System. First announced in 2021 by K2 using the Transit detection technique (producing an estimated primary transit depth of 0.0292% across the stellar disk), this world measures 2.03 Earth radii and has a measured mass of 4.78 Earth masses. Combining its mass and radius yields a mean bulk density of 3.15 g/cm³ (an intermediate density indicative of a deep water-ice mantle or dense volatile envelope), a surface gravity of 1.16 g⊕ (11.38 m/s²), and an escape velocity of 17.2 km/s.
In its orbital architecture around K2-342, K2-342 b completes one full revolution every 11.561 Earth days.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 861 K (+588°C / +1090°F), K2-342 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star K2-342 is classified as a stellar host with an effective photospheric temperature of 5,920 K, a radius of 1.09 R☉, a mass of 1.01 M☉, an estimated bolometric luminosity of 1.309 L☉. Stellar evolution modeling indicates a metallicity of [Fe/H] = -0.06 dex (near-solar heavy-element abundance). From Earth, K2-342 shines at apparent V-band magnitude 11.338 (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 | K2-342 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 5,920 K |
| Stellar Radius | 1.0900 R☉ |
| Stellar Mass | 1.0100 M☉ |
| Bolometric Luminosity | 1.309 L☉ |
| Metallicity [Fe/H] | -0.060 dex |
| Stellar Age | — |
| Apparent Magnitude | V: 11.338 · G: 11.070 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | — |
| Orbital Period | 11.561 days |
| Orbital Eccentricity (e) | Circular (0.00) |
| Orbital Inclination (i) | — |
| Mean Bulk Density | 3.15 g/cm³ (17.2 km/s vesc) |
| Insolation Flux | — |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 679.600 LY (208.357 pc) |