Kepler-1740 b
Astrophysical Synthesis & Habitability Characterization
Kepler-1740 b is a confirmed sub-neptune exoplanet orbiting the star Kepler-1740, located approximately 3463 light-years (1061.77 parsecs) from the Solar System. First announced in 2021 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.1133% across the stellar disk), this world measures 3.323 Earth radii (0.3 Jupiter radii) and has a measured mass of 11 Earth masses. Combining its mass and radius yields a mean bulk density of 1.65 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 1 g⊕ (9.81 m/s²), and an escape velocity of 20.4 km/s.
In its orbital architecture around Kepler-1740, Kepler-1740 b completes one full revolution every 8.172 Earth days at a semi-major axis of 0.0779 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 103.7 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 858 K (+585°C / +1085°F) and receiving 127.95 S⊕ (~174,140 W/m²), Kepler-1740 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star Kepler-1740 is classified as a stellar host with an effective photospheric temperature of 5,705 K, a radius of 0.905 R☉, a mass of 0.943 M☉, an estimated bolometric luminosity of 0.778 L☉. Stellar evolution modeling indicates a metallicity of [Fe/H] = -0.06 dex (near-solar heavy-element abundance). From Earth, Kepler-1740 shines at apparent V-band magnitude 15.454 (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-1740 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 5,705 K |
| Stellar Radius | 0.9050 R☉ |
| Stellar Mass | 0.9430 M☉ |
| Bolometric Luminosity | 0.778 L☉ |
| Metallicity [Fe/H] | -0.060 dex |
| Stellar Age | — |
| Apparent Magnitude | V: 15.454 · G: 15.286 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.077900 AU |
| Orbital Period | 8.172 days |
| Mean Orbital Velocity | 103.7 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 82.8000° |
| Mean Bulk Density | 1.65 g/cm³ (20.4 km/s vesc) |
| Insolation Flux | 127.9500 S⊕ (~174,140 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 3463.000 LY (1061.770 pc) |