PZ Tel b
Astrophysical Synthesis & Habitability Characterization
PZ Tel b is a confirmed gas giant exoplanet orbiting the star PZ Tel, located approximately 153.5 light-years (47.07 parsecs) from the Solar System. First announced in 2023 by W. M. Keck Observatory using the Imaging detection technique (resolved directly via high-contrast coronagraphic or interferometric imaging), this world measures 11.9 Earth radii (1.06 Jupiter radii) and has a measured mass of 8581.367 Earth masses (27 Jupiter masses). Combining its mass and radius yields a mean bulk density of 28.08 g/cm³ (an iron-enriched, high-compression rocky core), a surface gravity of 60.6 g⊕ (594.28 m/s²), and an escape velocity of 300.4 km/s.
In its orbital architecture around PZ Tel, PZ Tel b completes one full revolution every 44000 Earth days (120.47Julian years) at a semi-major axis of 27 AU (a wide outer-system orbit beyond Jupiter's 5.20 AU distance in our Solar System). Its mean orbital velocity is approximately 6.7 km/s (compared to Earth's 29.8 km/s). The planet follows a highly eccentric trajectory (e = 0.52, swinging from 12.96 AU at periapsis out to 41.04 AU at apoapsis), pointing to past dynamical scattering or secular gravitational perturbations.
❄️ Thermal Regime (Cryogenic Zone): With an equilibrium temperature of 54 K (-219°C / -362°F) and an incident flux of 0.00 S⊕ (~2 W/m²), surface water and volatile species on PZ Tel b would remain locked in cryogenic ice phases unless warmed by subsurface tidal or radiogenic heating.
The host star PZ Tel is classified as a solar-type yellow star of spectral type G9 IV with an effective photospheric temperature of 5,169 K, a radius of 1.2565 R☉, a mass of 1.36 M☉, an estimated bolometric luminosity of 1.011 L☉. Stellar evolution modeling indicates an estimated stellar age of 0.2 Gyr. From Earth, PZ Tel shines at apparent V-band magnitude 8.43 (accessible to binoculars and small amateur telescopes) 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: W. M. Keck Observatory · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | PZ Tel |
| Spectral Type | G9 IV |
| Effective Temp (Teff) | 5,169 K |
| Stellar Radius | 1.2565 R☉ |
| Stellar Mass | 1.3600 M☉ |
| Bolometric Luminosity | 1.011 L☉ |
| Metallicity [Fe/H] | — |
| Stellar Age | 0.200 Gyr |
| Apparent Magnitude | V: 8.430 · G: 8.099 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 27.000000 AU |
| Orbital Period | 44000 days |
| Mean Orbital Velocity | 6.7 km/s |
| Orbital Eccentricity (e) | 0.52000 |
| Orbital Inclination (i) | 91.7300° |
| Mean Bulk Density | 28.08 g/cm³ (300.4 km/s vesc) |
| Insolation Flux | 0.0014 S⊕ (~2 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 153.500 LY (47.065 pc) |