TOI-1224 b
Astrophysical Synthesis & Habitability Characterization
TOI-1224 b 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 0.228% across the stellar disk), this world measures 2.104 Earth radii and has a measured mass of 5.08 Earth masses. Combining its mass and radius yields a mean bulk density of 3.01 g/cm³ (an intermediate density indicative of a deep water-ice mantle or dense volatile envelope), a surface gravity of 1.15 g⊕ (11.28 m/s²), and an escape velocity of 17.4 km/s.
In its orbital architecture around TOI-1224, TOI-1224 b completes one full revolution every 4.178 Earth days at a semi-major axis of 0.0355 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 92.4 km/s (compared to Earth's 29.8 km/s).
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 541 K (+268°C / +514°F) and receiving 13.93 S⊕ (~18,958 W/m²), TOI-1224 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
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 b sharing its stellar neighborhood alongside TOI-1224 c.
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) | 0.035500 AU |
| Orbital Period | 4.178 days |
| Mean Orbital Velocity | 92.4 km/s |
| Orbital Eccentricity (e) | Circular (0.00) |
| Orbital Inclination (i) | 89.1900° |
| Mean Bulk Density | 3.01 g/cm³ (17.4 km/s vesc) |
| Insolation Flux | 13.9295 S⊕ (~18,958 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 121.800 LY (37.331 pc) |