KPS-1 b
Astrophysical Synthesis & Habitability Characterization
KPS-1 b is a confirmed gas giant exoplanet orbiting the star KPS-1, located approximately 856.8 light-years (262.71 parsecs) from the Solar System. First announced in 2018 by Acton Sky Portal Observatory using the Transit detection technique (producing an estimated primary transit depth of 1.3618% across the stellar disk), this world measures 11.545 Earth radii (1.03 Jupiter radii) and has a measured mass of 346.435 Earth masses (1.09 Jupiter masses). Combining its mass and radius yields a mean bulk density of 1.24 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 2.6 g⊕ (25.5 m/s²), and an escape velocity of 61.3 km/s.
In its orbital architecture around KPS-1, KPS-1 b completes one full revolution every 1.706 Earth days at a semi-major axis of 0.0269 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 171.5 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 1459 K (+1186°C / +2167°F) and receiving 729.00 S⊕ (~992,169 W/m²), KPS-1 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star KPS-1 is classified as an orange K-type star of spectral type K1 V with an effective photospheric temperature of 5,165 K, a radius of 0.907 R☉, a mass of 0.892 M☉, an estimated bolometric luminosity of 0.525 L☉. Stellar evolution modeling indicates a metallicity of [Fe/H] = 0.22 dex (metal-rich relative to the Sun). From Earth, KPS-1 shines at apparent V-band magnitude 12.97 (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: Acton Sky Portal Observatory · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | KPS-1 |
| Spectral Type | K1 V |
| Effective Temp (Teff) | 5,165 K |
| Stellar Radius | 0.9070 R☉ |
| Stellar Mass | 0.8920 M☉ |
| Bolometric Luminosity | 0.525 L☉ |
| Metallicity [Fe/H] | 0.220 dex |
| Stellar Age | — |
| Apparent Magnitude | V: 12.970 · G: 12.793 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.026900 AU |
| Orbital Period | 1.706 days |
| Mean Orbital Velocity | 171.5 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 83.2000° |
| Mean Bulk Density | 1.24 g/cm³ (61.3 km/s vesc) |
| Insolation Flux | 729.0000 S⊕ (~992,169 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 856.800 LY (262.706 pc) |