TOI-1422 c
Astrophysical Synthesis & Habitability Characterization
TOI-1422 c is a confirmed sub-neptune exoplanet orbiting the star TOI-1422, located approximately 506 light-years (155.14 parsecs) from the Solar System. First announced in 2025 by Roque de los Muchachos Observatory using the Radial Velocity detection technique (measuring periodic Doppler reflex motion in the host star's spectrum), this world measures 2.61 Earth radii and has a measured mass of 14 Earth masses. Combining its mass and radius yields a mean bulk density of 4.34 g/cm³ (a terrestrial silicate-iron composition comparable to Earth (5.51 g/cm³)), a surface gravity of 2.06 g⊕ (20.2 m/s²), and an escape velocity of 25.9 km/s.
In its orbital architecture around TOI-1422, TOI-1422 c completes one full revolution every 34.563 Earth days at a semi-major axis of 0.205 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 64.5 km/s (compared to Earth's 29.8 km/s). Its moderate orbital eccentricity of e = 0.2 carries the world between 0.164 AU at periapsis and 0.246 AU at apoapsis, driving measurable seasonal insolation cycles.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 628 K (+355°C / +671°F) and receiving 26.56 S⊕ (~36,142 W/m²), TOI-1422 c orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star TOI-1422 is classified as a solar-type yellow star of spectral type G2 V with an effective photospheric temperature of 5,840 K, a radius of 1.019 R☉, a mass of 0.9903 M☉, an estimated bolometric luminosity of 1.084 L☉. Stellar evolution modeling indicates an estimated stellar age of 4.6 Gyr and a metallicity of [Fe/H] = -0.028 dex (near-solar heavy-element abundance). From Earth, TOI-1422 shines at apparent V-band magnitude 10.622 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere. The TOI-1422 system is a multi-planet architecture hosting 2 confirmed worlds, with TOI-1422 c sharing its stellar neighborhood alongside TOI-1422 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: Roque de los Muchachos Observatory · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | TOI-1422 |
| Spectral Type | G2 V |
| Effective Temp (Teff) | 5,840 K |
| Stellar Radius | 1.0190 R☉ |
| Stellar Mass | 0.9903 M☉ |
| Bolometric Luminosity | 1.084 L☉ |
| Metallicity [Fe/H] | -0.028 dex |
| Stellar Age | 4.600 Gyr |
| Apparent Magnitude | V: 10.622 · G: 10.552 |
| System Architecture | 1 Star, 2 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.205000 AU |
| Orbital Period | 34.563 days |
| Mean Orbital Velocity | 64.5 km/s |
| Orbital Eccentricity (e) | 0.20000 |
| Orbital Inclination (i) | 89.7700° |
| Mean Bulk Density | 4.34 g/cm³ (25.9 km/s vesc) |
| Insolation Flux | 26.5556 S⊕ (~36,142 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 506.000 LY (155.141 pc) |