Kepler-454 d
Astrophysical Synthesis & Habitability Characterization
Kepler-454 d is a confirmed gas giant exoplanet orbiting the star Kepler-454, located approximately 753 light-years (230.87 parsecs) from the Solar System. First announced in 2023 by Roque de los Muchachos Observatory using the Radial Velocity detection technique (measuring periodic Doppler reflex motion in the host star's spectrum), this world measures 13.3 Earth radii (1.19 Jupiter radii) and has a measured mass of 734.184 Earth masses (2.31 Jupiter masses). Combining its mass and radius yields a mean bulk density of 1.72 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 4.15 g⊕ (40.7 m/s²), and an escape velocity of 83.1 km/s.
In its orbital architecture around Kepler-454, Kepler-454 d completes one full revolution every 4073 Earth days (11.15Julian years) at a semi-major axis of 5.1 AU (corresponding to the middle-system regime between Mars at 1.52 AU and Jupiter at 5.20 AU). Its mean orbital velocity is approximately 13.6 km/s (compared to Earth's 29.8 km/s). Its moderate orbital eccentricity of e = 0.089 carries the world between 4.6461 AU at periapsis and 5.5539 AU at apoapsis, driving measurable seasonal insolation cycles.
❄️ Thermal Regime (Cryogenic Zone): With an equilibrium temperature of 125 K (-148°C / -234°F) and an incident flux of 0.04 S⊕ (~59 W/m²), surface water and volatile species on Kepler-454 d would remain locked in cryogenic ice phases unless warmed by subsurface tidal or radiogenic heating.
The host star Kepler-454 is classified as a stellar host with an effective photospheric temperature of 5,687 K, a radius of 1.066 R☉, a mass of 1.03 M☉, an estimated bolometric luminosity of 1.066 L☉. Stellar evolution modeling indicates an estimated stellar age of 5.25 Gyr and a metallicity of [Fe/H] = 0.32 dex (metal-rich relative to the Sun). From Earth, Kepler-454 shines at apparent V-band magnitude 11.567 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere. The Kepler-454 system is a multi-planet architecture hosting 3 confirmed worlds, with Kepler-454 d sharing its stellar neighborhood alongside Kepler-454 b, Kepler-454 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: Roque de los Muchachos Observatory · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | Kepler-454 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 5,687 K |
| Stellar Radius | 1.0660 R☉ |
| Stellar Mass | 1.0300 M☉ |
| Bolometric Luminosity | 1.066 L☉ |
| Metallicity [Fe/H] | 0.320 dex |
| Stellar Age | 5.250 Gyr |
| Apparent Magnitude | V: 11.567 · G: 11.440 |
| System Architecture | 2 Stars, 3 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 5.100000 AU |
| Orbital Period | 4073 days |
| Mean Orbital Velocity | 13.6 km/s |
| Orbital Eccentricity (e) | 0.08900 |
| Orbital Inclination (i) | — |
| Mean Bulk Density | 1.72 g/cm³ (83.1 km/s vesc) |
| Insolation Flux | 0.0434 S⊕ (~59 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 753.000 LY (230.869 pc) |