EPIC 201757695.02
Astrophysical Synthesis & Habitability Characterization
EPIC 201757695.02 is a confirmed terrestrial exoplanet orbiting the star EPIC 201757695, located approximately 1883.9 light-years (577.6 parsecs) from the Solar System. First announced in 2020 by K2 using the Transit detection technique (producing an estimated primary transit depth of 0.0162% across the stellar disk), this world measures 0.908 Earth radii and has a measured mass of 0.688 Earth masses. Combining its mass and radius yields a mean bulk density of 5.07 g/cm³ (a terrestrial silicate-iron composition comparable to Earth (5.51 g/cm³)), a surface gravity of 0.83 g⊕ (8.14 m/s²), and an escape velocity of 9.7 km/s.
In its orbital architecture around EPIC 201757695, EPIC 201757695.02 completes one full revolution every 2.048 Earth days at a semi-major axis of 0.0296 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 157.3 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 1025 K (+752°C / +1386°F) and receiving 494.20 S⊕ (~672,609 W/m²), EPIC 201757695.02 orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star EPIC 201757695 is classified as a stellar host with an effective photospheric temperature of 4,520 K, a radius of 0.655 R☉, a mass of 0.727 M☉, an estimated bolometric luminosity of 0.161 L☉. Stellar evolution modeling indicates a metallicity of [Fe/H] = -0.003 dex (near-solar heavy-element abundance). From Earth, EPIC 201757695 shines at apparent V-band magnitude 14.974 (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 | EPIC 201757695 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 4,520 K |
| Stellar Radius | 0.6550 R☉ |
| Stellar Mass | 0.7270 M☉ |
| Bolometric Luminosity | 0.161 L☉ |
| Metallicity [Fe/H] | -0.003 dex |
| Stellar Age | — |
| Apparent Magnitude | V: 14.974 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.029600 AU |
| Orbital Period | 2.048 days |
| Mean Orbital Velocity | 157.3 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 89.2757° |
| Mean Bulk Density | 5.07 g/cm³ (9.7 km/s vesc) |
| Insolation Flux | 494.2020 S⊕ (~672,609 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 1883.900 LY (577.600 pc) |