Kepler-2001 b
Astrophysical Synthesis & Habitability Characterization
Kepler-2001 b is a confirmed terrestrial exoplanet orbiting the star Kepler-2001, located approximately 2532.8 light-years (776.55 parsecs) from the Solar System. First announced in 2023 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.0153% across the stellar disk), this world measures 1.04 Earth radii and has a measured mass of 1.12 Earth masses. Combining its mass and radius yields a mean bulk density of 5.49 g/cm³ (a terrestrial silicate-iron composition comparable to Earth (5.51 g/cm³)), a surface gravity of 1.04 g⊕ (10.2 m/s²), and an escape velocity of 11.6 km/s.
In its orbital architecture around Kepler-2001, Kepler-2001 b completes one full revolution every 1.09 Earth days at a semi-major axis of 0.0197 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 196.6 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 1402 K (+1129°C / +2064°F) and receiving 911.28 S⊕ (~1,240,252 W/m²), Kepler-2001 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star Kepler-2001 is classified as a stellar host with an effective photospheric temperature of 5,081 K, a radius of 0.77 R☉, a mass of 0.864 M☉, an estimated bolometric luminosity of 0.355 L☉. Stellar evolution modeling indicates an estimated stellar age of 4 Gyr and a metallicity of [Fe/H] = 0.12 dex (metal-rich relative to the Sun). From Earth, Kepler-2001 shines at apparent V-band magnitude 15.981 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere. The Kepler-2001 system is a multi-planet architecture hosting 2 confirmed worlds, with Kepler-2001 b sharing its stellar neighborhood alongside Kepler-2001 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-2001 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 5,081 K |
| Stellar Radius | 0.7700 R☉ |
| Stellar Mass | 0.8640 M☉ |
| Bolometric Luminosity | 0.355 L☉ |
| Metallicity [Fe/H] | 0.120 dex |
| Stellar Age | 4.000 Gyr |
| Apparent Magnitude | V: 15.981 · G: 15.773 |
| System Architecture | 1 Star, 2 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.019700 AU |
| Orbital Period | 1.09 days |
| Mean Orbital Velocity | 196.6 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 83.7100° |
| Mean Bulk Density | 5.49 g/cm³ (11.6 km/s vesc) |
| Insolation Flux | 911.2800 S⊕ (~1,240,252 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 2532.800 LY (776.550 pc) |