K2-316 b
Astrophysical Synthesis & Habitability Characterization
K2-316 b is a confirmed super-earth exoplanet orbiting the star K2-316, located approximately 366.9 light-years (112.49 parsecs) from the Solar System. First announced in 2020 by K2 using the Transit detection technique (producing an estimated primary transit depth of 0.1035% across the stellar disk), this world measures 1.33 Earth radii and has a measured mass of 2.33 Earth masses. Combining its mass and radius yields a mean bulk density of 5.46 g/cm³ (a terrestrial silicate-iron composition comparable to Earth (5.51 g/cm³)), a surface gravity of 1.32 g⊕ (12.94 m/s²), and an escape velocity of 14.8 km/s.
In its orbital architecture around K2-316, K2-316 b completes one full revolution every 1.133 Earth days at a semi-major axis of 0.0147 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 141.1 km/s (compared to Earth's 29.8 km/s).
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 841 K (+568°C / +1054°F) and receiving 68.51 S⊕ (~93,236 W/m²), K2-316 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star K2-316 is classified as a stellar host with an effective photospheric temperature of 3,436 K, a radius of 0.379 R☉, a mass of 0.408 M☉, an estimated bolometric luminosity of 0.018 L☉. From Earth, K2-316 shines at apparent V-band magnitude 17.14 (faint and requiring research-grade or CCD telescopic photometry) in the Southern celestial hemisphere. The K2-316 system is a multi-planet architecture hosting 2 confirmed worlds, with K2-316 b sharing its stellar neighborhood alongside K2-316 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 | K2-316 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 3,436 K |
| Stellar Radius | 0.3790 R☉ |
| Stellar Mass | 0.4080 M☉ |
| Bolometric Luminosity | 0.018 L☉ |
| Metallicity [Fe/H] | — |
| Stellar Age | — |
| Apparent Magnitude | V: 17.140 · G: 15.514 |
| System Architecture | 1 Star, 2 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.014700 AU |
| Orbital Period | 1.133 days |
| Mean Orbital Velocity | 141.1 km/s |
| Orbital Eccentricity (e) | Circular (0.00) |
| Orbital Inclination (i) | 87.0200° |
| Mean Bulk Density | 5.46 g/cm³ (14.8 km/s vesc) |
| Insolation Flux | 68.5057 S⊕ (~93,236 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 366.900 LY (112.486 pc) |