TOI-237 c
Astrophysical Synthesis & Habitability Characterization
TOI-237 c is a confirmed terrestrial exoplanet orbiting the star TOI-237, located approximately 124.2 light-years (38.08 parsecs) from the Solar System. First announced in 2026 by La Silla Observatory using the Transit detection technique (producing an estimated primary transit depth of 0.2892% across the stellar disk), this world measures 1.206 Earth radii and has a measured mass of 1.9 Earth masses. Combining its mass and radius yields a mean bulk density of 5.97 g/cm³ (a terrestrial silicate-iron composition comparable to Earth (5.51 g/cm³)), a surface gravity of 1.31 g⊕ (12.85 m/s²), and an escape velocity of 14 km/s.
In its orbital architecture around TOI-237, TOI-237 c completes one full revolution every 1.745 Earth days at a semi-major axis of 0.016 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 99.8 km/s (compared to Earth's 29.8 km/s).
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 515 K (+242°C / +468°F) and receiving 16.00 S⊕ (~21,776 W/m²), TOI-237 c orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star TOI-237 is classified as a low-mass red dwarf of spectral type M4.5 V with an effective photospheric temperature of 3,226 K, a radius of 0.2056 R☉, a mass of 0.1698 M☉, an estimated bolometric luminosity of 0.00411 L☉. Stellar evolution modeling indicates an estimated stellar age of 4.5 Gyr and a metallicity of [Fe/H] = -0.344 dex (metal-poor relative to the Sun). From Earth, TOI-237 shines at apparent V-band magnitude 16.37 (faint and requiring research-grade or CCD telescopic photometry) in the Southern celestial hemisphere. The TOI-237 system is a multi-planet architecture hosting 2 confirmed worlds, with TOI-237 c sharing its stellar neighborhood alongside TOI-237 b.
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: La Silla Observatory · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | TOI-237 |
| Spectral Type | M4.5 V |
| Effective Temp (Teff) | 3,226 K |
| Stellar Radius | 0.2056 R☉ |
| Stellar Mass | 0.1698 M☉ |
| Bolometric Luminosity | 0.00411 L☉ |
| Metallicity [Fe/H] | -0.344 dex |
| Stellar Age | 4.500 Gyr |
| Apparent Magnitude | V: 16.370 · G: 14.754 |
| System Architecture | 1 Star, 2 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.016000 AU |
| Orbital Period | 1.745 days |
| Mean Orbital Velocity | 99.8 km/s |
| Orbital Eccentricity (e) | Circular (0.00) |
| Orbital Inclination (i) | 89.1400° |
| Mean Bulk Density | 5.97 g/cm³ (14 km/s vesc) |
| Insolation Flux | 16.0000 S⊕ (~21,776 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 124.200 LY (38.075 pc) |