GJ 4274 c
Astrophysical Synthesis & Habitability Characterization
GJ 4274 c is a confirmed sub-neptune exoplanet orbiting the star GJ 4274, located approximately 23.6 light-years (7.24 parsecs) from the Solar System. First announced in 2026 by Mauna Kea Observatory using the Radial Velocity detection technique (measuring periodic Doppler reflex motion in the host star's spectrum), this world measures 2.83 Earth radii and has a measured mass of 8.39 Earth masses. Combining its mass and radius yields a mean bulk density of 2.04 g/cm³ (an intermediate density indicative of a deep water-ice mantle or dense volatile envelope), a surface gravity of 1.05 g⊕ (10.3 m/s²), and an escape velocity of 19.3 km/s.
In its orbital architecture around GJ 4274, GJ 4274 c completes one full revolution every 69.57 Earth days at a semi-major axis of 0.186 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 29.1 km/s (compared to Earth's 29.8 km/s).
❄️ Thermal Regime (Cryogenic Zone): With an equilibrium temperature of 157 K (-116°C / -177°F) and an incident flux of 0.10 S⊕ (~136 W/m²), surface water and volatile species on GJ 4274 c would remain locked in cryogenic ice phases unless warmed by subsurface tidal or radiogenic heating.
The host star GJ 4274 is classified as a low-mass red dwarf of spectral type M4.5 V with an effective photospheric temperature of 3,228 K, a radius of 0.19 R☉, a mass of 0.18 M☉, an estimated bolometric luminosity of 0.00352 L☉. Stellar evolution modeling indicates an estimated stellar age of 0.12 Gyr and a metallicity of [Fe/H] = -0.19 dex (metal-poor relative to the Sun). From Earth, GJ 4274 shines at apparent V-band magnitude 13.31 (faint and requiring research-grade or CCD telescopic photometry) in the Southern celestial hemisphere. The GJ 4274 system is a multi-planet architecture hosting 2 confirmed worlds, with GJ 4274 c sharing its stellar neighborhood alongside GJ 4274 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: Mauna Kea Observatory · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | GJ 4274 |
| Spectral Type | M4.5 V |
| Effective Temp (Teff) | 3,228 K |
| Stellar Radius | 0.1900 R☉ |
| Stellar Mass | 0.1800 M☉ |
| Bolometric Luminosity | 0.00352 L☉ |
| Metallicity [Fe/H] | -0.190 dex |
| Stellar Age | 0.120 Gyr |
| Apparent Magnitude | V: 13.310 · G: 11.554 |
| System Architecture | 1 Star, 2 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.186000 AU |
| Orbital Period | 69.57 days |
| Mean Orbital Velocity | 29.1 km/s |
| Orbital Eccentricity (e) | Circular (0.00) |
| Orbital Inclination (i) | — |
| Mean Bulk Density | 2.04 g/cm³ (19.3 km/s vesc) |
| Insolation Flux | 0.1000 S⊕ (~136 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 23.600 LY (7.236 pc) |