TOI-2081 b
Astrophysical Synthesis & Habitability Characterization
TOI-2081 b is a confirmed sub-neptune exoplanet orbiting the star TOI-2081, located approximately 203.3 light-years (62.35 parsecs) from the Solar System. First announced in 2022 by Transiting Exoplanet Survey Satellite (TESS) using the Transit detection technique (producing an estimated primary transit depth of 0.1227% across the stellar disk), this world measures 2.04 Earth radii and has a measured mass of 4.82 Earth masses. Combining its mass and radius yields a mean bulk density of 3.13 g/cm³ (an intermediate density indicative of a deep water-ice mantle or dense volatile envelope), a surface gravity of 1.16 g⊕ (11.38 m/s²), and an escape velocity of 17.2 km/s.
In its orbital architecture around TOI-2081, TOI-2081 b completes one full revolution every 10.505 Earth days at a semi-major axis of 0.0752 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 77.9 km/s (compared to Earth's 29.8 km/s).
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 488 K (+215°C / +419°F) and receiving 8.10 S⊕ (~11,024 W/m²), TOI-2081 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star TOI-2081 is classified as a low-mass red dwarf of spectral type M1.0 with an effective photospheric temperature of 3,800 K, a radius of 0.534 R☉, a mass of 0.54 M☉, an estimated bolometric luminosity of 0.053 L☉. Stellar evolution modeling indicates a metallicity of [Fe/H] = -0.5 dex (metal-poor relative to the Sun). From Earth, TOI-2081 shines at apparent V-band magnitude 13.369 (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-2081 |
| Spectral Type | M1.0 |
| Effective Temp (Teff) | 3,800 K |
| Stellar Radius | 0.5340 R☉ |
| Stellar Mass | 0.5400 M☉ |
| Bolometric Luminosity | 0.053 L☉ |
| Metallicity [Fe/H] | -0.500 dex |
| Stellar Age | — |
| Apparent Magnitude | V: 13.369 · G: 12.659 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.075200 AU |
| Orbital Period | 10.505 days |
| Mean Orbital Velocity | 77.9 km/s |
| Orbital Eccentricity (e) | Circular (0.00) |
| Orbital Inclination (i) | 89.3400° |
| Mean Bulk Density | 3.13 g/cm³ (17.2 km/s vesc) |
| Insolation Flux | 8.1000 S⊕ (~11,024 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 203.300 LY (62.345 pc) |