Kepler-437 b
Astrophysical Synthesis & Habitability Characterization
Kepler-437 b is a confirmed sub-neptune exoplanet orbiting the star Kepler-437, located approximately 991.5 light-years (304 parsecs) from the Solar System. First announced in 2015 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.0832% across the stellar disk), this world measures 2.14 Earth radii and has a measured mass of 5.22 Earth masses. Combining its mass and radius yields a mean bulk density of 2.94 g/cm³ (an intermediate density indicative of a deep water-ice mantle or dense volatile envelope), a surface gravity of 1.14 g⊕ (11.18 m/s²), and an escape velocity of 17.5 km/s.
In its orbital architecture around Kepler-437, Kepler-437 b completes one full revolution every 66.651 Earth days at a semi-major axis of 0.288 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 47 km/s (compared to Earth's 29.8 km/s). With a near-circular eccentricity of e = 0.02 (ranging from 0.2822 AU at periapsis to 0.2938 AU at apoapsis), the planet experiences minimal orbital distance variation.
✓ Classified as a Temperate Habitable Zone Candidate.
With an estimated equilibrium temperature of 308 K (+35°C / +95°F) and an incident stellar irradiance of 2.15 S⊕ (~2,926 W/m²), Kepler-437 b orbits within the empirical circumstellar habitable zone where a rocky surface under sufficient atmospheric pressure can maintain liquid surface water.
The host star Kepler-437 is classified as a stellar host with an effective photospheric temperature of 4,551 K, a radius of 0.68 R☉, a mass of 0.707 M☉, an estimated bolometric luminosity of 0.178 L☉. Stellar evolution modeling indicates an estimated stellar age of 2.9 Gyr and a metallicity of [Fe/H] = 0 dex (near-solar heavy-element abundance). From Earth, Kepler-437 shines at apparent V-band magnitude 14.628 (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: Kepler · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | Kepler-437 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 4,551 K |
| Stellar Radius | 0.6800 R☉ |
| Stellar Mass | 0.7070 M☉ |
| Bolometric Luminosity | 0.178 L☉ |
| Metallicity [Fe/H] | 0.000 dex |
| Stellar Age | 2.900 Gyr |
| Apparent Magnitude | V: 14.628 · G: 14.362 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.288000 AU |
| Orbital Period | 66.651 days |
| Mean Orbital Velocity | 47 km/s |
| Orbital Eccentricity (e) | 0.02000 |
| Orbital Inclination (i) | 89.9000° |
| Mean Bulk Density | 2.94 g/cm³ (17.5 km/s vesc) |
| Insolation Flux | 2.1500 S⊕ (~2,926 W/m²) |
| Habitable Zone Status | ★ Temperate Zone |
| Celestial Distance | 991.500 LY (304.000 pc) |