Gl 725 A b
Astrophysical Synthesis & Habitability Characterization
Gl 725 A b is a confirmed super-earth exoplanet orbiting the star Gl 725 A, located approximately 11.5 light-years (3.52 parsecs) from the Solar System. First announced in 2025 by Multiple Observatories using the Radial Velocity detection technique (measuring periodic Doppler reflex motion in the host star's spectrum), this world measures 1.48 Earth radii and has a measured mass of 2.78 Earth masses. Combining its mass and radius yields a mean bulk density of 4.73 g/cm³ (a terrestrial silicate-iron composition comparable to Earth (5.51 g/cm³)), a surface gravity of 1.27 g⊕ (12.45 m/s²), and an escape velocity of 15.3 km/s.
In its orbital architecture around Gl 725 A, Gl 725 A b completes one full revolution every 11.22 Earth days at a semi-major axis of 0.068 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 65.9 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 376 K (+103°C / +217°F) and receiving 3.36 S⊕ (~4,569 W/m²), Gl 725 A b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star Gl 725 A is classified as a low-mass red dwarf of spectral type M3 with an effective photospheric temperature of 3,433 K, a radius of 0.351 R☉, a mass of 0.33 M☉, an estimated bolometric luminosity of 0.015 L☉. Stellar evolution modeling indicates an estimated stellar age of 6.2 Gyr and a metallicity of [Fe/H] = -0.19 dex (metal-poor relative to the Sun). From Earth, Gl 725 A shines at apparent V-band magnitude 8.94 (accessible to binoculars and small amateur telescopes) 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: Multiple Observatories · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | Gl 725 A |
| Spectral Type | M3 |
| Effective Temp (Teff) | 3,433 K |
| Stellar Radius | 0.3510 R☉ |
| Stellar Mass | 0.3300 M☉ |
| Bolometric Luminosity | 0.015 L☉ |
| Metallicity [Fe/H] | -0.190 dex |
| Stellar Age | 6.200 Gyr |
| Apparent Magnitude | V: 8.940 · G: 7.849 |
| System Architecture | 2 Stars, 2 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.068000 AU |
| Orbital Period | 11.22 days |
| Mean Orbital Velocity | 65.9 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | — |
| Mean Bulk Density | 4.73 g/cm³ (15.3 km/s vesc) |
| Insolation Flux | 3.3572 S⊕ (~4,569 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 11.500 LY (3.521 pc) |