TIC 77319217 b

Astrophysical Synthesis & Habitability Characterization

TIC 77319217 b is a confirmed sub-neptune exoplanet orbiting the star TIC 77319217, located approximately 872.9 light-years (267.62 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 0.0579% across the stellar disk), this world measures 3.109 Earth radii (0.28 Jupiter radii) and has a measured mass of 9.85 Earth masses. Combining its mass and radius yields a mean bulk density of 1.81 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 1.02 g⊕ (10 m/s²), and an escape velocity of 19.9 km/s.

In its orbital architecture around TIC 77319217, TIC 77319217 b completes one full revolution every 7.548 Earth days.

☁️ Atmospheric Regime (Volatile / Gas Envelope): With a radius of 3.109 R⊕, TIC 77319217 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 TIC 77319217 is classified as a stellar host with an effective photospheric temperature of 5,962 K, a radius of 1.1844 R☉, a mass of 1.16 M☉, an estimated bolometric luminosity of 1.59 L☉. From Earth, TIC 77319217 shines at apparent V-band magnitude 11.497 (faint and requiring research-grade or CCD telescopic photometry) in the Southern celestial hemisphere.

Discovery Facility: Transiting Exoplanet Survey Satellite (TESS) · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).