KELT-1 b
Astrophysical Synthesis & Habitability Characterization
KELT-1 b is a confirmed gas giant exoplanet orbiting the star KELT-1, located approximately 875.5 light-years (268.43 parsecs) from the Solar System. First announced in 2012 by KELT using the Transit detection technique (producing an estimated primary transit depth of 0.6013% across the stellar disk), this world measures 12.442 Earth radii (1.11 Jupiter radii) and has a measured mass of 8654.15 Earth masses (27.23 Jupiter masses). Combining its mass and radius yields a mean bulk density of 24.78 g/cm³ (an iron-enriched, high-compression rocky core), a surface gravity of 55.9 g⊕ (548.19 m/s²), and an escape velocity of 295 km/s.
In its orbital architecture around KELT-1, KELT-1 b completes one full revolution every 1.218 Earth days at a semi-major axis of 0.02466 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 220.3 km/s (compared to Earth's 29.8 km/s). With a near-circular eccentricity of e = 0.0099 (ranging from 0.0244 AU at periapsis to 0.0249 AU at apoapsis), the planet experiences minimal orbital distance variation.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 2361 K (+2088°C / +3790°F) and receiving 5,165.92 S⊕ (~7,030,817 W/m²), KELT-1 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star KELT-1 is classified as a stellar host with an effective photospheric temperature of 6,516 K, a radius of 1.471 R☉, a mass of 1.335 M☉, an estimated bolometric luminosity of 3.5 L☉. Stellar evolution modeling indicates a metallicity of [Fe/H] = 0.052 dex (metal-rich relative to the Sun). From Earth, KELT-1 shines at apparent V-band magnitude 10.632 (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: KELT · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | KELT-1 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 6,516 K |
| Stellar Radius | 1.4710 R☉ |
| Stellar Mass | 1.3350 M☉ |
| Bolometric Luminosity | 3.5 L☉ |
| Metallicity [Fe/H] | 0.052 dex |
| Stellar Age | — |
| Apparent Magnitude | V: 10.632 · G: 10.591 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.024660 AU |
| Orbital Period | 1.218 days |
| Mean Orbital Velocity | 220.3 km/s |
| Orbital Eccentricity (e) | 0.00990 |
| Orbital Inclination (i) | 87.8000° |
| Mean Bulk Density | 24.78 g/cm³ (295 km/s vesc) |
| Insolation Flux | 5165.9200 S⊕ (~7,030,817 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 875.500 LY (268.430 pc) |