EPIC 201754305 d
Astrophysical Synthesis & Habitability Characterization
EPIC 201754305 d is a confirmed terrestrial exoplanet orbiting the star K2-16, located approximately 1092.5 light-years (334.97 parsecs) from the Solar System. First announced in 2019 by K2 using the Transit detection technique (producing an estimated primary transit depth of 0.0301% across the stellar disk), this world measures 1.03 Earth radii and has a measured mass of 1.08 Earth masses. Combining its mass and radius yields a mean bulk density of 5.45 g/cm³ (a terrestrial silicate-iron composition comparable to Earth (5.51 g/cm³)), a surface gravity of 1.02 g⊕ (10 m/s²), and an escape velocity of 11.5 km/s.
In its orbital architecture around K2-16, EPIC 201754305 d completes one full revolution every 2.716 Earth days.
ℹ️ Thermal & Atmospheric Regime: Current photometric and spectroscopic constraints for EPIC 201754305 d place it outside the conservative habitable zone definition pending further atmospheric characterization.
The host star K2-16 is classified as an orange K-type star of spectral type K3 V with an effective photospheric temperature of 4,761 K, a radius of 0.544 R☉, a mass of 0.67 M☉, an estimated bolometric luminosity of 0.136 L☉. Stellar evolution modeling indicates a metallicity of [Fe/H] = -0.33 dex (metal-poor relative to the Sun). From Earth, K2-16 shines at apparent V-band magnitude 14.668 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere. The K2-16 system is a multi-planet architecture hosting 3 confirmed worlds, with EPIC 201754305 d sharing its stellar neighborhood alongside K2-16 b, K2-16 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 | K2-16 |
| Spectral Type | K3 V |
| Effective Temp (Teff) | 4,761 K |
| Stellar Radius | 0.5440 R☉ |
| Stellar Mass | 0.6700 M☉ |
| Bolometric Luminosity | 0.136 L☉ |
| Metallicity [Fe/H] | -0.330 dex |
| Stellar Age | — |
| Apparent Magnitude | V: 14.668 · G: 14.323 |
| System Architecture | 1 Star, 3 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | — |
| Orbital Period | 2.716 days |
| Orbital Eccentricity (e) | Circular (0.00) |
| Orbital Inclination (i) | — |
| Mean Bulk Density | 5.45 g/cm³ (11.5 km/s vesc) |
| Insolation Flux | — |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 1092.500 LY (334.967 pc) |