Kepler-1761 b
Astrophysical Synthesis & Habitability Characterization
Kepler-1761 b is a confirmed super-earth exoplanet orbiting the star Kepler-1761, located approximately 721.4 light-years (221.19 parsecs) from the Solar System. First announced in 2021 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.0575% across the stellar disk), this world measures 1.391 Earth radii and has a measured mass of 2.51 Earth masses. Combining its mass and radius yields a mean bulk density of 5.14 g/cm³ (a terrestrial silicate-iron composition comparable to Earth (5.51 g/cm³)), a surface gravity of 1.3 g⊕ (12.75 m/s²), and an escape velocity of 15 km/s.
In its orbital architecture around Kepler-1761, Kepler-1761 b completes one full revolution every 4.044 Earth days at a semi-major axis of 0.0413 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 111.1 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 613 K (+340°C / +644°F) and receiving 33.34 S⊕ (~45,376 W/m²), Kepler-1761 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star Kepler-1761 is classified as a stellar host with an effective photospheric temperature of 3,871 K, a radius of 0.532 R☉, a mass of 0.573 M☉, an estimated bolometric luminosity of 0.057 L☉. Stellar evolution modeling indicates an estimated stellar age of 3.9 Gyr and a metallicity of [Fe/H] = 0.07 dex (metal-rich relative to the Sun). From Earth, Kepler-1761 shines at apparent V-band magnitude 15.619 (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-1761 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 3,871 K |
| Stellar Radius | 0.5320 R☉ |
| Stellar Mass | 0.5730 M☉ |
| Bolometric Luminosity | 0.057 L☉ |
| Metallicity [Fe/H] | 0.070 dex |
| Stellar Age | 3.900 Gyr |
| Apparent Magnitude | V: 15.619 · G: 14.898 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.041300 AU |
| Orbital Period | 4.044 days |
| Mean Orbital Velocity | 111.1 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 78.4200° |
| Mean Bulk Density | 5.14 g/cm³ (15 km/s vesc) |
| Insolation Flux | 33.3400 S⊕ (~45,376 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 721.400 LY (221.186 pc) |