TOI-1774.01
Astrophysical Synthesis & Habitability Characterization
TOI-1774.01 is a confirmed sub-neptune exoplanet orbiting the star TOI-1774, located approximately 176 light-years (53.97 parsecs) from the Solar System. First announced in 2021 by Transiting Exoplanet Survey Satellite (TESS) using the Transit detection technique (producing an estimated primary transit depth of 0.0508% across the stellar disk), this world measures 2.78 Earth radii and has a measured mass of 8.5 Earth masses. Combining its mass and radius yields a mean bulk density of 2.18 g/cm³ (an intermediate density indicative of a deep water-ice mantle or dense volatile envelope), a surface gravity of 1.1 g⊕ (10.79 m/s²), and an escape velocity of 19.6 km/s.
In its orbital architecture around TOI-1774, TOI-1774.01 completes one full revolution every 16.71 Earth days. Its moderate orbital eccentricity of e = 0.05 driving measurable seasonal insolation cycles.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 824 K (+551°C / +1024°F) and receiving 73.76 S⊕ (~100,389 W/m²), TOI-1774.01 orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star TOI-1774 is classified as a stellar host with an effective photospheric temperature of 5,746 K, a radius of 1.1303 R☉, a mass of 0.991 M☉, an estimated bolometric luminosity of 1.25 L☉. Stellar evolution modeling indicates an estimated stellar age of 7.4 Gyr and a metallicity of [Fe/H] = -0.02 dex (near-solar heavy-element abundance). From Earth, TOI-1774 shines at apparent V-band magnitude 8.25 (accessible to binoculars and small amateur telescopes) in the Northern celestial hemisphere. The TOI-1774 system is a multi-planet architecture hosting 2 confirmed worlds, with TOI-1774.01 sharing its stellar neighborhood alongside HD 85426 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-1774 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 5,746 K |
| Stellar Radius | 1.1303 R☉ |
| Stellar Mass | 0.9910 M☉ |
| Bolometric Luminosity | 1.25 L☉ |
| Metallicity [Fe/H] | -0.020 dex |
| Stellar Age | 7.400 Gyr |
| Apparent Magnitude | V: 8.250 · G: 8.082 |
| System Architecture | 1 Star, 2 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | — |
| Orbital Period | 16.71 days |
| Orbital Eccentricity (e) | 0.05000 |
| Orbital Inclination (i) | 89.4000° |
| Mean Bulk Density | 2.18 g/cm³ (19.6 km/s vesc) |
| Insolation Flux | 73.7609 S⊕ (~100,389 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 176.000 LY (53.974 pc) |