TOI-6677 b
Astrophysical Synthesis & Habitability Characterization
TOI-6677 b is a confirmed sub-neptune exoplanet orbiting the star TOI-6677, located approximately 1110.6 light-years (340.52 parsecs) from the Solar System. First announced in 2026 by Transiting Exoplanet Survey Satellite (TESS) using the Transit detection technique (producing an estimated primary transit depth of 0.1158% across the stellar disk), this world measures 5.835 Earth radii (0.52 Jupiter radii) and has a measured mass of 28.7 Earth masses. Combining its mass and radius yields a mean bulk density of 0.8 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 0.84 g⊕ (8.24 m/s²), and an escape velocity of 24.8 km/s.
In its orbital architecture around TOI-6677, TOI-6677 b completes one full revolution every 5.451 Earth days.
☁️ Atmospheric Regime (Volatile / Gas Envelope): With a radius of 5.835 R⊕, TOI-6677 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-6677 is classified as a stellar host with an effective photospheric temperature of 6,572 K, a radius of 1.5717 R☉, a mass of 1.45 M☉, an estimated bolometric luminosity of 4.134 L☉. From Earth, TOI-6677 shines at apparent V-band magnitude 10.765 (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-6677 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 6,572 K |
| Stellar Radius | 1.5717 R☉ |
| Stellar Mass | 1.4500 M☉ |
| Bolometric Luminosity | 4.134 L☉ |
| Metallicity [Fe/H] | — |
| Stellar Age | — |
| Apparent Magnitude | V: 10.765 · G: 10.779 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | — |
| Orbital Period | 5.451 days |
| Orbital Eccentricity (e) | Circular (0.00) |
| Orbital Inclination (i) | 86.8039° |
| Mean Bulk Density | 0.8 g/cm³ (24.8 km/s vesc) |
| Insolation Flux | 2.0900 S⊕ (~2,844 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 1110.600 LY (340.520 pc) |