COCONUTS-2 b
Astrophysical Synthesis & Habitability Characterization
COCONUTS-2 b is a confirmed gas giant exoplanet orbiting the star COCONUTS-2 A, located approximately 35.5 light-years (10.89 parsecs) from the Solar System. First announced in 2021 by NASA Infrared Telescope Facility (IRTF) using the Imaging detection technique (resolved directly via high-contrast coronagraphic or interferometric imaging), this world measures 12.576 Earth radii (1.12 Jupiter radii) and has a measured mass of 2383.713 Earth masses (7.5 Jupiter masses). Combining its mass and radius yields a mean bulk density of 6.61 g/cm³ (an iron-enriched, high-compression rocky core), a surface gravity of 15.07 g⊕ (147.79 m/s²), and an escape velocity of 154 km/s.
In its orbital architecture around COCONUTS-2 A, COCONUTS-2 b completes one full revolution every 402000000 Earth days (1100616.02Julian years) at a semi-major axis of 7506 AU (a wide outer-system orbit beyond Jupiter's 5.20 AU distance in our Solar System). Its mean orbital velocity is approximately 0.2 km/s (compared to Earth's 29.8 km/s).
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 493 K (+220°C / +428°F), COCONUTS-2 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star COCONUTS-2 A is classified as a low-mass red dwarf of spectral type M3 V with an effective photospheric temperature of 3,552 K, a radius of 0.366 R☉, a mass of 0.4 M☉, an estimated bolometric luminosity of 0.019 L☉. Stellar evolution modeling indicates an estimated stellar age of 0.414 Gyr and a metallicity of [Fe/H] = 0 dex (near-solar heavy-element abundance). From Earth, COCONUTS-2 A shines at apparent V-band magnitude 11.298 (faint and requiring research-grade or CCD telescopic photometry) in the Southern 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: NASA Infrared Telescope Facility (IRTF) · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | COCONUTS-2 A |
| Spectral Type | M3 V |
| Effective Temp (Teff) | 3,552 K |
| Stellar Radius | 0.3660 R☉ |
| Stellar Mass | 0.4000 M☉ |
| Bolometric Luminosity | 0.019 L☉ |
| Metallicity [Fe/H] | 0.000 dex |
| Stellar Age | 0.414 Gyr |
| Apparent Magnitude | V: 11.298 · G: 10.146 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 7506.000000 AU |
| Orbital Period | 402000000 days |
| Mean Orbital Velocity | 0.2 km/s |
| Orbital Eccentricity (e) | Circular (0.00) |
| Orbital Inclination (i) | — |
| Mean Bulk Density | 6.61 g/cm³ (154 km/s vesc) |
| Insolation Flux | 0.0000 S⊕ |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 35.500 LY (10.886 pc) |