Kepler-451 d
Astrophysical Synthesis & Habitability Characterization
Kepler-451 d is a confirmed gas giant exoplanet orbiting the star 2MASS J19383260+4603591, located approximately 1292.7 light-years (396.33 parsecs) from the Solar System. First announced in 2022 by Multiple Observatories using the Eclipse Timing Variations detection technique, this world measures 13.5 Earth radii (1.2 Jupiter radii) and has a measured mass of 559.378 Earth masses (1.76 Jupiter masses). Combining its mass and radius yields a mean bulk density of 1.25 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 3.07 g⊕ (30.11 m/s²), and an escape velocity of 72 km/s.
In its orbital architecture around 2MASS J19383260+4603591, Kepler-451 d completes one full revolution every 43 Earth days. The orbit is modeled as circular (e = 0.00), maintaining a constant stellar distance throughout its year.
☁️ Atmospheric Regime (Volatile / Gas Envelope): With a radius of 13.500 R⊕, Kepler-451 d exceeds the empirical ~1.8–2.2 R⊕ Fulton radius valley threshold, indicating a substantial hydrogen-helium or supercritical volatile envelope without a conventional solid terrestrial surface.
The host star 2MASS J19383260+4603591 is classified as a stellar host with an effective photospheric temperature of 29,564 K, a radius of 0.203 R☉, a mass of 0.48 M☉, an estimated bolometric luminosity of 28.245 L☉. Stellar evolution modeling indicates a metallicity of [Fe/H] = -0.092 dex (near-solar heavy-element abundance). From Earth, 2MASS J19383260+4603591 shines at apparent V-band magnitude 12.651 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere. The 2MASS J19383260+4603591 system is a multi-planet architecture hosting 3 confirmed worlds, with Kepler-451 d sharing its stellar neighborhood alongside 2MASS J19383260+4603591 b, Kepler-451 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: Multiple Observatories · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | 2MASS J19383260+4603591 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 29,564 K |
| Stellar Radius | 0.2030 R☉ |
| Stellar Mass | 0.4800 M☉ |
| Bolometric Luminosity | 28.245 L☉ |
| Metallicity [Fe/H] | -0.092 dex |
| Stellar Age | — |
| Apparent Magnitude | V: 12.651 · G: 12.138 |
| System Architecture | 2 Stars, 3 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | — |
| Orbital Period | 43 days |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | — |
| Mean Bulk Density | 1.25 g/cm³ (72 km/s vesc) |
| Insolation Flux | — |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 1292.700 LY (396.332 pc) |