Kepler-1742 b
Astrophysical Synthesis & Habitability Characterization
Kepler-1742 b is a confirmed sub-neptune exoplanet orbiting the star Kepler-1742, located approximately 2183.9 light-years (669.57 parsecs) from the Solar System. First announced in 2021 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.0553% across the stellar disk), this world measures 2.178 Earth radii and has a measured mass of 5.38 Earth masses. Combining its mass and radius yields a mean bulk density of 2.87 g/cm³ (an intermediate density indicative of a deep water-ice mantle or dense volatile envelope), a surface gravity of 1.13 g⊕ (11.08 m/s²), and an escape velocity of 17.6 km/s.
In its orbital architecture around Kepler-1742, Kepler-1742 b completes one full revolution every 49.478 Earth days at a semi-major axis of 0.2587 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 56.9 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 462 K (+189°C / +372°F) and receiving 10.73 S⊕ (~14,604 W/m²), Kepler-1742 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star Kepler-1742 is classified as a stellar host with an effective photospheric temperature of 5,776 K, a radius of 0.849 R☉, a mass of 0.939 M☉, an estimated bolometric luminosity of 0.72 L☉. Stellar evolution modeling indicates an estimated stellar age of 0.5 Gyr and a metallicity of [Fe/H] = -0.18 dex (metal-poor relative to the Sun). From Earth, Kepler-1742 shines at apparent V-band magnitude 14.512 (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-1742 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 5,776 K |
| Stellar Radius | 0.8490 R☉ |
| Stellar Mass | 0.9390 M☉ |
| Bolometric Luminosity | 0.72 L☉ |
| Metallicity [Fe/H] | -0.180 dex |
| Stellar Age | 0.500 Gyr |
| Apparent Magnitude | V: 14.512 · G: 14.374 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.258700 AU |
| Orbital Period | 49.478 days |
| Mean Orbital Velocity | 56.9 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 89.9800° |
| Mean Bulk Density | 2.87 g/cm³ (17.6 km/s vesc) |
| Insolation Flux | 10.7300 S⊕ (~14,604 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 2183.900 LY (669.573 pc) |