TOI-1269 b
Astrophysical Synthesis & Habitability Characterization
TOI-1269 b is a confirmed sub-neptune exoplanet orbiting the star TOI-1269, located approximately 561.4 light-years (172.14 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 0.0667% across the stellar disk), this world measures 2.401 Earth radii and has a measured mass of 6.4 Earth masses. Combining its mass and radius yields a mean bulk density of 2.55 g/cm³ (an intermediate density indicative of a deep water-ice mantle or dense volatile envelope), a surface gravity of 1.11 g⊕ (10.89 m/s²), and an escape velocity of 18.3 km/s.
In its orbital architecture around TOI-1269, TOI-1269 b completes one full revolution every 4.253 Earth days at a semi-major axis of 0.0496 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 126.9 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 1005 K (+732°C / +1350°F) and receiving 231.20 S⊕ (~314,668 W/m²), TOI-1269 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star TOI-1269 is classified as a stellar host with an effective photospheric temperature of 5,499 K, a radius of 0.8521 R☉, a mass of 0.9027 M☉, an estimated bolometric luminosity of 0.596 L☉. Stellar evolution modeling indicates an estimated stellar age of 3.1 Gyr and a metallicity of [Fe/H] = -0.049 dex (near-solar heavy-element abundance). From Earth, TOI-1269 shines at apparent V-band magnitude 11.618 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere. The TOI-1269 system is a multi-planet architecture hosting 2 confirmed worlds, with TOI-1269 b sharing its stellar neighborhood alongside TOI-1269 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-1269 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 5,499 K |
| Stellar Radius | 0.8521 R☉ |
| Stellar Mass | 0.9027 M☉ |
| Bolometric Luminosity | 0.596 L☉ |
| Metallicity [Fe/H] | -0.049 dex |
| Stellar Age | 3.100 Gyr |
| Apparent Magnitude | V: 11.618 · G: 11.471 |
| System Architecture | 1 Star, 2 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.049600 AU |
| Orbital Period | 4.253 days |
| Mean Orbital Velocity | 126.9 km/s |
| Orbital Eccentricity (e) | 0.00000 |
| Orbital Inclination (i) | — |
| Mean Bulk Density | 2.55 g/cm³ (18.3 km/s vesc) |
| Insolation Flux | 231.2034 S⊕ (~314,668 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 561.400 LY (172.138 pc) |