TOI-6954 b
Astrophysical Synthesis & Habitability Characterization
TOI-6954 b is a confirmed sub-neptune exoplanet orbiting the star TOI-6954, located approximately 619.8 light-years (190.04 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 0.1238% across the stellar disk), this world measures 3.635 Earth radii (0.32 Jupiter radii) and has a measured mass of 12.8 Earth masses. Combining its mass and radius yields a mean bulk density of 1.47 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 0.97 g⊕ (9.51 m/s²), and an escape velocity of 21 km/s.
In its orbital architecture around TOI-6954, TOI-6954 b completes one full revolution every 4.021 Earth days.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 930 K (+657°C / +1215°F) and receiving 124.57 S⊕ (~169,538 W/m²), TOI-6954 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star TOI-6954 is classified as a stellar host with an effective photospheric temperature of 5,171 K, a radius of 0.9471 R☉, a mass of 0.834 M☉, an estimated bolometric luminosity of 0.575 L☉. Stellar evolution modeling indicates a metallicity of [Fe/H] = 0.03 dex (near-solar heavy-element abundance). From Earth, TOI-6954 shines at apparent V-band magnitude 12.262 (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-6954 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 5,171 K |
| Stellar Radius | 0.9471 R☉ |
| Stellar Mass | 0.8340 M☉ |
| Bolometric Luminosity | 0.575 L☉ |
| Metallicity [Fe/H] | 0.030 dex |
| Stellar Age | — |
| Apparent Magnitude | V: 12.262 · G: 11.991 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | — |
| Orbital Period | 4.021 days |
| Orbital Eccentricity (e) | Circular (0.00) |
| Orbital Inclination (i) | 88.3602° |
| Mean Bulk Density | 1.47 g/cm³ (21 km/s vesc) |
| Insolation Flux | 124.5690 S⊕ (~169,538 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 619.800 LY (190.042 pc) |