2MASS J19383260+4603591 b
Astrophysical Synthesis & Habitability Characterization
2MASS J19383260+4603591 b is a confirmed gas giant exoplanet orbiting the star 2MASS J19383260+4603591, located approximately 1292.7 light-years (396.33 parsecs) from the Solar System. First announced in 2015 by Kepler using the Eclipse Timing Variations detection technique, this world measures 13.4 Earth radii (1.2 Jupiter radii) and has a measured mass of 603.877 Earth masses (1.9 Jupiter masses). Combining its mass and radius yields a mean bulk density of 1.38 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 3.36 g⊕ (32.95 m/s²), and an escape velocity of 75.1 km/s.
In its orbital architecture around 2MASS J19383260+4603591, 2MASS J19383260+4603591 b completes one full revolution every 406 Earth days (1.11Julian years) at a semi-major axis of 0.92 AU (comparable to the inner terrestrial zone between Venus, Earth at 1.00 AU, and Mars at 1.52 AU). Its mean orbital velocity is approximately 24.7 km/s (compared to Earth's 29.8 km/s). The planet follows a highly eccentric trajectory (e = 0.33, swinging from 0.6164 AU at periapsis out to 1.2236 AU at apoapsis), pointing to past dynamical scattering or secular gravitational perturbations.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 670 K (+397°C / +747°F) and receiving 33.30 S⊕ (~45,319 W/m²), 2MASS J19383260+4603591 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star 2MASS J19383260+4603591 is classified as a stellar host with an effective photospheric temperature of 29,564 K, a radius of 0.203 R☉, a mass of 0.48 M☉, an estimated bolometric luminosity of 28.245 L☉. Stellar evolution modeling indicates a metallicity of [Fe/H] = -0.092 dex (near-solar heavy-element abundance). From Earth, 2MASS J19383260+4603591 shines at apparent V-band magnitude 12.651 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere. The 2MASS J19383260+4603591 system is a multi-planet architecture hosting 3 confirmed worlds, with 2MASS J19383260+4603591 b sharing its stellar neighborhood alongside Kepler-451 d, Kepler-451 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 | 2MASS J19383260+4603591 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 29,564 K |
| Stellar Radius | 0.2030 R☉ |
| Stellar Mass | 0.4800 M☉ |
| Bolometric Luminosity | 28.245 L☉ |
| Metallicity [Fe/H] | -0.092 dex |
| Stellar Age | — |
| Apparent Magnitude | V: 12.651 · G: 12.138 |
| System Architecture | 2 Stars, 3 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.920000 AU |
| Orbital Period | 406 days |
| Mean Orbital Velocity | 24.7 km/s |
| Orbital Eccentricity (e) | 0.33000 |
| Orbital Inclination (i) | — |
| Mean Bulk Density | 1.38 g/cm³ (75.1 km/s vesc) |
| Insolation Flux | 33.2985 S⊕ (~45,319 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 1292.700 LY (396.332 pc) |