GJ 1132 c
Astrophysical Synthesis & Habitability Characterization
GJ 1132 c is a confirmed super-earth exoplanet orbiting the star GJ 1132, located approximately 41.1 light-years (12.61 parsecs) from the Solar System. First announced in 2018 by La Silla Observatory using the Radial Velocity detection technique (measuring periodic Doppler reflex motion in the host star's spectrum), this world measures 1.52 Earth radii and has a measured mass of 2.91 Earth masses. Combining its mass and radius yields a mean bulk density of 4.57 g/cm³ (a terrestrial silicate-iron composition comparable to Earth (5.51 g/cm³)), a surface gravity of 1.26 g⊕ (12.36 m/s²), and an escape velocity of 15.5 km/s.
In its orbital architecture around GJ 1132, GJ 1132 c completes one full revolution every 8.929 Earth days at a semi-major axis of 0.0476 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 58 km/s (compared to Earth's 29.8 km/s). Its moderate orbital eccentricity of e = 0.19 carries the world between 0.0386 AU at periapsis and 0.0566 AU at apoapsis, driving measurable seasonal insolation cycles.
✓ Classified as a Temperate Habitable Zone Candidate.
With an estimated equilibrium temperature of 300 K (+27°C / +81°F) and an incident stellar irradiance of 2.11 S⊕ (~2,865 W/m²), GJ 1132 c orbits within the empirical circumstellar habitable zone where a rocky surface under sufficient atmospheric pressure can maintain liquid surface water.
The host star GJ 1132 is classified as a low-mass red dwarf of spectral type M4.5 V with an effective photospheric temperature of 3,090 K, a radius of 0.226 R☉, a mass of 0.198 M☉, an estimated bolometric luminosity of 0.00418 L☉. Stellar evolution modeling indicates an estimated stellar age of 5 Gyr and a metallicity of [Fe/H] = -0.18 dex (metal-poor relative to the Sun). From Earth, GJ 1132 shines at apparent V-band magnitude 13.68 (faint and requiring research-grade or CCD telescopic photometry) in the Southern celestial hemisphere. The GJ 1132 system is a multi-planet architecture hosting 2 confirmed worlds, with GJ 1132 c sharing its stellar neighborhood alongside GJ 1132 b.
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: La Silla Observatory · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | GJ 1132 |
| Spectral Type | M4.5 V |
| Effective Temp (Teff) | 3,090 K |
| Stellar Radius | 0.2260 R☉ |
| Stellar Mass | 0.1980 M☉ |
| Bolometric Luminosity | 0.00418 L☉ |
| Metallicity [Fe/H] | -0.180 dex |
| Stellar Age | 5.000 Gyr |
| Apparent Magnitude | V: 13.680 · G: 12.138 |
| System Architecture | 1 Star, 2 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.047600 AU |
| Orbital Period | 8.929 days |
| Mean Orbital Velocity | 58 km/s |
| Orbital Eccentricity (e) | 0.19000 |
| Orbital Inclination (i) | — |
| Mean Bulk Density | 4.57 g/cm³ (15.5 km/s vesc) |
| Insolation Flux | 2.1053 S⊕ (~2,865 W/m²) |
| Habitable Zone Status | ★ Temperate Zone |
| Celestial Distance | 41.100 LY (12.613 pc) |