TOI-1224 c
Astrophysical Synthesis & Habitability Characterization
TOI-1224 c is a confirmed sub-neptune exoplanet orbiting the star TOI-1224, located approximately 121.8 light-years (37.33 parsecs) from the Solar System. First announced in 2024 by Transiting Exoplanet Survey Satellite (TESS) using the Transit detection technique (producing an estimated primary transit depth of 0.4283% across the stellar disk), this world measures 2.884 Earth radii and has a measured mass of 8.67 Earth masses. Combining its mass and radius yields a mean bulk density of 1.99 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 1.04 g⊕ (10.2 m/s²), and an escape velocity of 19.4 km/s.
In its orbital architecture around TOI-1224, TOI-1224 c completes one full revolution every 17.945 Earth days. The orbit is modeled as circular (e = 0.00), maintaining a constant stellar distance throughout its year.
☁️ Atmospheric Regime (Volatile / Gas Envelope): With a radius of 2.884 R⊕, TOI-1224 c exceeds the empirical ~1.8–2.2 R⊕ Fulton radius valley threshold, indicating a substantial hydrogen-helium or supercritical volatile envelope without a conventional solid terrestrial surface.
The host star TOI-1224 is classified as a stellar host with an effective photospheric temperature of 3,326 K, a radius of 0.404 R☉, a mass of 0.4 M☉, an estimated bolometric luminosity of 0.018 L☉. Stellar evolution modeling indicates an estimated stellar age of 0.21 Gyr. From Earth, TOI-1224 shines at apparent V-band magnitude 13.95 (faint and requiring research-grade or CCD telescopic photometry) in the Southern celestial hemisphere. The TOI-1224 system is a multi-planet architecture hosting 2 confirmed worlds, with TOI-1224 c sharing its stellar neighborhood alongside TOI-1224 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: Transiting Exoplanet Survey Satellite (TESS) · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | TOI-1224 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 3,326 K |
| Stellar Radius | 0.4040 R☉ |
| Stellar Mass | 0.4000 M☉ |
| Bolometric Luminosity | 0.018 L☉ |
| Metallicity [Fe/H] | — |
| Stellar Age | 0.210 Gyr |
| Apparent Magnitude | V: 13.950 · G: 12.782 |
| System Architecture | 1 Star, 2 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | — |
| Orbital Period | 17.945 days |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | — |
| Mean Bulk Density | 1.99 g/cm³ (19.4 km/s vesc) |
| Insolation Flux | 1.9952 S⊕ (~2,715 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 121.800 LY (37.331 pc) |