NGTS-16 b
Astrophysical Synthesis & Habitability Characterization
NGTS-16 b is a confirmed gas giant exoplanet orbiting the star NGTS-16, located approximately 2929.4 light-years (898.17 parsecs) from the Solar System. First announced in 2021 by Next-Generation Transit Survey (NGTS) using the Transit detection technique (producing an estimated primary transit depth of 1.213% across the stellar disk), this world measures 14.572 Earth radii (1.3 Jupiter radii) and has a measured mass of 211.992 Earth masses (0.67 Jupiter masses). Combining its mass and radius yields a mean bulk density of 0.38 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 1 g⊕ (9.81 m/s²), and an escape velocity of 42.7 km/s.
In its orbital architecture around NGTS-16, NGTS-16 b completes one full revolution every 4.845 Earth days at a semi-major axis of 0.0523 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 117.4 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.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 1177 K (+904°C / +1659°F) and receiving 480.00 S⊕ (~653,280 W/m²), NGTS-16 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star NGTS-16 is classified as a solar-type yellow star of spectral type G7 V with an effective photospheric temperature of 5,550 K, a radius of 1.213 R☉, a mass of 1.002 M☉, an estimated bolometric luminosity of 1.253 L☉. Stellar evolution modeling indicates an estimated stellar age of 10.29 Gyr and a metallicity of [Fe/H] = 0.35 dex (metal-rich relative to the Sun). From Earth, NGTS-16 shines at apparent V-band magnitude 14.529 (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: Next-Generation Transit Survey (NGTS) · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | NGTS-16 |
| Spectral Type | G7 V |
| Effective Temp (Teff) | 5,550 K |
| Stellar Radius | 1.2130 R☉ |
| Stellar Mass | 1.0020 M☉ |
| Bolometric Luminosity | 1.253 L☉ |
| Metallicity [Fe/H] | 0.350 dex |
| Stellar Age | 10.290 Gyr |
| Apparent Magnitude | V: 14.529 · G: 14.231 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.052300 AU |
| Orbital Period | 4.845 days |
| Mean Orbital Velocity | 117.4 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | — |
| Mean Bulk Density | 0.38 g/cm³ (42.7 km/s vesc) |
| Insolation Flux | 480.0000 S⊕ (~653,280 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 2929.400 LY (898.168 pc) |