GJ 536 c
Astrophysical Synthesis & Habitability Characterization
GJ 536 c is a confirmed sub-neptune exoplanet orbiting the star GJ 536, located approximately 34 light-years (10.41 parsecs) from the Solar System. First announced in 2025 by Multiple Facilities using the Radial Velocity detection technique (measuring periodic Doppler reflex motion in the host star's spectrum), this world measures 2.3 Earth radii and has a measured mass of 5.89 Earth masses. Combining its mass and radius yields a mean bulk density of 2.67 g/cm³ (an intermediate density indicative of a deep water-ice mantle or dense volatile envelope), a surface gravity of 1.11 g⊕ (10.89 m/s²), and an escape velocity of 17.9 km/s.
In its orbital architecture around GJ 536, GJ 536 c completes one full revolution every 32.761 Earth days at a semi-major axis of 0.1617 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 53.7 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.
☁️ Atmospheric Regime (Volatile / Gas Envelope): With a radius of 2.300 R⊕, GJ 536 c exceeds the empirical ~1.8–2.2 R⊕ Fulton radius valley threshold, indicating a substantial hydrogen-helium or supercritical volatile envelope without a conventional solid terrestrial surface.
The host star GJ 536 is classified as a low-mass red dwarf of spectral type M1 V with an effective photospheric temperature of 3,641 K, a radius of 0.529 R☉, a mass of 0.528 M☉, an estimated bolometric luminosity of 0.044 L☉. Stellar evolution modeling indicates an estimated stellar age of 4.2 Gyr and a metallicity of [Fe/H] = -0.08 dex (near-solar heavy-element abundance). From Earth, GJ 536 shines at apparent V-band magnitude 9.71 (accessible to binoculars and small amateur telescopes) in the Southern celestial hemisphere. The GJ 536 system is a multi-planet architecture hosting 2 confirmed worlds, with GJ 536 c sharing its stellar neighborhood alongside GJ 536 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: Multiple Facilities · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | GJ 536 |
| Spectral Type | M1 V |
| Effective Temp (Teff) | 3,641 K |
| Stellar Radius | 0.5290 R☉ |
| Stellar Mass | 0.5280 M☉ |
| Bolometric Luminosity | 0.044 L☉ |
| Metallicity [Fe/H] | -0.080 dex |
| Stellar Age | 4.200 Gyr |
| Apparent Magnitude | V: 9.710 · G: 8.859 |
| System Architecture | 1 Star, 2 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.161700 AU |
| Orbital Period | 32.761 days |
| Mean Orbital Velocity | 53.7 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | — |
| Mean Bulk Density | 2.67 g/cm³ (17.9 km/s vesc) |
| Insolation Flux | 1.6920 S⊕ (~2,303 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 34.000 LY (10.409 pc) |