TOI-1680 b
Astrophysical Synthesis & Habitability Characterization
TOI-1680 b is a confirmed super-earth exoplanet orbiting the star TOI-1680, located approximately 121.4 light-years (37.22 parsecs) from the Solar System. First announced in 2023 by Transiting Exoplanet Survey Satellite (TESS) using the Transit detection technique (producing an estimated primary transit depth of 0.4073% across the stellar disk), this world measures 1.466 Earth radii and has a measured mass of 2.75 Earth masses. Combining its mass and radius yields a mean bulk density of 4.81 g/cm³ (a terrestrial silicate-iron composition comparable to Earth (5.51 g/cm³)), a surface gravity of 1.28 g⊕ (12.55 m/s²), and an escape velocity of 15.3 km/s.
In its orbital architecture around TOI-1680, TOI-1680 b completes one full revolution every 4.803 Earth days at a semi-major axis of 0.03144 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 71.2 km/s (compared to Earth's 29.8 km/s).
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 404 K (+131°C / +268°F) and receiving 4.41 S⊕ (~6,002 W/m²), TOI-1680 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star TOI-1680 is classified as a low-mass red dwarf of spectral type M4.5+/-0.5 with an effective photospheric temperature of 3,225 K, a radius of 0.2106 R☉, a mass of 0.1798 M☉, an estimated bolometric luminosity of 0.00430 L☉. Stellar evolution modeling indicates a metallicity of [Fe/H] = 0.04 dex (near-solar heavy-element abundance). From Earth, TOI-1680 shines at apparent V-band magnitude 15.87 (faint and requiring research-grade or CCD telescopic photometry) in the Northern 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-1680 |
| Spectral Type | M4.5+/-0.5 |
| Effective Temp (Teff) | 3,225 K |
| Stellar Radius | 0.2106 R☉ |
| Stellar Mass | 0.1798 M☉ |
| Bolometric Luminosity | 0.00430 L☉ |
| Metallicity [Fe/H] | 0.040 dex |
| Stellar Age | — |
| Apparent Magnitude | V: 15.870 · G: 14.646 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.031440 AU |
| Orbital Period | 4.803 days |
| Mean Orbital Velocity | 71.2 km/s |
| Orbital Eccentricity (e) | Circular (0.00) |
| Orbital Inclination (i) | 89.5800° |
| Mean Bulk Density | 4.81 g/cm³ (15.3 km/s vesc) |
| Insolation Flux | 4.4100 S⊕ (~6,002 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 121.400 LY (37.221 pc) |