EPIC 228836835 b
Astrophysical Synthesis & Habitability Characterization
EPIC 228836835 b is a confirmed terrestrial exoplanet orbiting the star EPIC 228836835, located approximately 489.6 light-years (150.12 parsecs) from the Solar System. First announced in 2021 by K2 using the Transit detection technique (producing an estimated primary transit depth of 0.0993% across the stellar disk), this world measures 1.1 Earth radii and has a measured mass of 1.37 Earth masses. Combining its mass and radius yields a mean bulk density of 5.68 g/cm³ (a terrestrial silicate-iron composition comparable to Earth (5.51 g/cm³)), a surface gravity of 1.13 g⊕ (11.08 m/s²), and an escape velocity of 12.5 km/s.
In its orbital architecture around EPIC 228836835, EPIC 228836835 b completes one full revolution every 0.728 Earth days.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 932 K (+659°C / +1218°F), EPIC 228836835 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star EPIC 228836835 is classified as a stellar host with an effective photospheric temperature of 3,782 K, a radius of 0.32 R☉, a mass of 0.4182 M☉, an estimated bolometric luminosity of 0.019 L☉. Stellar evolution modeling indicates a metallicity of [Fe/H] = -0.18 dex (metal-poor relative to the Sun). From Earth, EPIC 228836835 shines at apparent V-band magnitude 16.77 (faint and requiring research-grade or CCD telescopic photometry) in the Southern 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 228836835 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 3,782 K |
| Stellar Radius | 0.3200 R☉ |
| Stellar Mass | 0.4182 M☉ |
| Bolometric Luminosity | 0.019 L☉ |
| Metallicity [Fe/H] | -0.180 dex |
| Stellar Age | — |
| Apparent Magnitude | V: 16.770 · G: 15.419 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | — |
| Orbital Period | 0.728 days |
| Orbital Eccentricity (e) | Circular (0.00) |
| Orbital Inclination (i) | 89.7000° |
| Mean Bulk Density | 5.68 g/cm³ (12.5 km/s vesc) |
| Insolation Flux | — |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 489.600 LY (150.124 pc) |