TOI-1227 b
Astrophysical Synthesis & Habitability Characterization
TOI-1227 b is a confirmed gas giant exoplanet orbiting the star TOI-1227, located approximately 328.2 light-years (100.64 parsecs) from the Solar System. First announced in 2022 by Transiting Exoplanet Survey Satellite (TESS) using the Transit detection technique (producing an estimated primary transit depth of 2.4557% across the stellar disk), this world measures 9.572 Earth radii (0.85 Jupiter radii) and has a measured mass of 66.5 Earth masses (0.21 Jupiter masses). Combining its mass and radius yields a mean bulk density of 0.42 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 0.73 g⊕ (7.16 m/s²), and an escape velocity of 29.5 km/s.
In its orbital architecture around TOI-1227, TOI-1227 b completes one full revolution every 27.364 Earth days at a semi-major axis of 0.0886 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 35.2 km/s (compared to Earth's 29.8 km/s).
☁️ Atmospheric Regime (Volatile / Gas Envelope): With a radius of 9.572 R⊕, TOI-1227 b 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-1227 is classified as a low-mass red dwarf of spectral type M4.5V-M5V with an effective photospheric temperature of 3,072 K, a radius of 0.56 R☉, a mass of 0.17 M☉, an estimated bolometric luminosity of 0.025 L☉. Stellar evolution modeling indicates an estimated stellar age of 0.011 Gyr. From Earth, TOI-1227 shines at apparent V-band magnitude 16.999 (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: Transiting Exoplanet Survey Satellite (TESS) · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | TOI-1227 |
| Spectral Type | M4.5V-M5V |
| Effective Temp (Teff) | 3,072 K |
| Stellar Radius | 0.5600 R☉ |
| Stellar Mass | 0.1700 M☉ |
| Bolometric Luminosity | 0.025 L☉ |
| Metallicity [Fe/H] | — |
| Stellar Age | 0.011 Gyr |
| Apparent Magnitude | V: 16.999 · G: 15.251 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.088600 AU |
| Orbital Period | 27.364 days |
| Mean Orbital Velocity | 35.2 km/s |
| Orbital Eccentricity (e) | Circular (0.00) |
| Orbital Inclination (i) | 88.5710° |
| Mean Bulk Density | 0.42 g/cm³ (29.5 km/s vesc) |
| Insolation Flux | 3.2100 S⊕ (~4,369 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 328.200 LY (100.641 pc) |