NGTS-14 A b
Astrophysical Synthesis & Habitability Characterization
NGTS-14 A b is a confirmed sub-neptune exoplanet orbiting the star NGTS-14 A, located approximately 1050.7 light-years (322.15 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 0.2937% across the stellar disk), this world measures 4.977 Earth radii (0.44 Jupiter radii) and has a measured mass of 29.24 Earth masses. Combining its mass and radius yields a mean bulk density of 1.31 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 1.18 g⊕ (11.57 m/s²), and an escape velocity of 27.1 km/s.
In its orbital architecture around NGTS-14 A, NGTS-14 A b completes one full revolution every 3.536 Earth days at a semi-major axis of 0.0403 AU (an ultra-close orbit less than one-seventh of Mercury's 0.387 AU distance from the Sun, where strong stellar tidal forces typically induce synchronous rotation). Its mean orbital velocity is approximately 124 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 1143 K (+870°C / +1598°F) and receiving 191.78 S⊕ (~261,015 W/m²), NGTS-14 A b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star NGTS-14 A is classified as an orange K-type star of spectral type K1 V with an effective photospheric temperature of 5,187 K, a radius of 0.842 R☉, a mass of 0.898 M☉, an estimated bolometric luminosity of 0.46 L☉. Stellar evolution modeling indicates an estimated stellar age of 5.9 Gyr and a metallicity of [Fe/H] = 0.1 dex (metal-rich relative to the Sun). From Earth, NGTS-14 A shines at apparent V-band magnitude 13.268 (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-14 A |
| Spectral Type | K1 V |
| Effective Temp (Teff) | 5,187 K |
| Stellar Radius | 0.8420 R☉ |
| Stellar Mass | 0.8980 M☉ |
| Bolometric Luminosity | 0.46 L☉ |
| Metallicity [Fe/H] | 0.100 dex |
| Stellar Age | 5.900 Gyr |
| Apparent Magnitude | V: 13.268 · G: 13.099 |
| System Architecture | 2 Stars, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.040300 AU |
| Orbital Period | 3.536 days |
| Mean Orbital Velocity | 124 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | 86.7000° |
| Mean Bulk Density | 1.31 g/cm³ (27.1 km/s vesc) |
| Insolation Flux | 191.7820 S⊕ (~261,015 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 1050.700 LY (322.148 pc) |