Kepler-416 d
Astrophysical Synthesis & Habitability Characterization
Kepler-416 d is a confirmed super-earth exoplanet orbiting the star Kepler-416, located approximately 2253.1 light-years (690.82 parsecs) from the Solar System. First announced in 2023 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.0209% across the stellar disk), this world measures 1.61 Earth radii and has a measured mass of 3.22 Earth masses. Combining its mass and radius yields a mean bulk density of 4.25 g/cm³ (a terrestrial silicate-iron composition comparable to Earth (5.51 g/cm³)), a surface gravity of 1.24 g⊕ (12.16 m/s²), and an escape velocity of 15.8 km/s.
In its orbital architecture around Kepler-416, Kepler-416 d completes one full revolution every 3.076 Earth days at a semi-major axis of 0.0407 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 143.9 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 1253 K (+980°C / +1796°F) and receiving 583.25 S⊕ (~793,803 W/m²), Kepler-416 d orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star Kepler-416 is classified as a stellar host with an effective photospheric temperature of 5,670 K, a radius of 1.022 R☉, a mass of 0.949 M☉, an estimated bolometric luminosity of 0.969 L☉. Stellar evolution modeling indicates an estimated stellar age of 2.69 Gyr and a metallicity of [Fe/H] = 0.06 dex (metal-rich relative to the Sun). From Earth, Kepler-416 shines at apparent V-band magnitude 14.166 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere. The Kepler-416 system is a multi-planet architecture hosting 3 confirmed worlds, with Kepler-416 d sharing its stellar neighborhood alongside Kepler-416 b, Kepler-416 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: Kepler · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | Kepler-416 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 5,670 K |
| Stellar Radius | 1.0220 R☉ |
| Stellar Mass | 0.9490 M☉ |
| Bolometric Luminosity | 0.969 L☉ |
| Metallicity [Fe/H] | 0.060 dex |
| Stellar Age | 2.690 Gyr |
| Apparent Magnitude | V: 14.166 · G: 14.020 |
| System Architecture | 1 Star, 3 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.040700 AU |
| Orbital Period | 3.076 days |
| Mean Orbital Velocity | 143.9 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 83.7800° |
| Mean Bulk Density | 4.25 g/cm³ (15.8 km/s vesc) |
| Insolation Flux | 583.2500 S⊕ (~793,803 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 2253.100 LY (690.819 pc) |