CoRoT-7 d
Astrophysical Synthesis & Habitability Characterization
CoRoT-7 d is a confirmed sub-neptune exoplanet orbiting the star CoRoT-7, located approximately 521.5 light-years (159.91 parsecs) from the Solar System. First announced in 2022 by La Silla Observatory using the Radial Velocity detection technique (measuring periodic Doppler reflex motion in the host star's spectrum), this world measures 4.31 Earth radii (0.38 Jupiter radii) and has a measured mass of 17.142 Earth masses. Combining its mass and radius yields a mean bulk density of 1.18 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 0.92 g⊕ (9.02 m/s²), and an escape velocity of 22.3 km/s.
In its orbital architecture around CoRoT-7, CoRoT-7 d completes one full revolution every 8.966 Earth days.
☁️ Atmospheric Regime (Volatile / Gas Envelope): With a radius of 4.310 R⊕, CoRoT-7 d exceeds the empirical ~1.8–2.2 R⊕ Fulton radius valley threshold, indicating a substantial hydrogen-helium or supercritical volatile envelope without a conventional solid terrestrial surface.
The host star CoRoT-7 is classified as a solar-type yellow star of spectral type G9 V with an effective photospheric temperature of 5,250 K, a radius of 0.8389 R☉, a mass of 0.915 M☉, an estimated bolometric luminosity of 0.48 L☉. Stellar evolution modeling indicates an estimated stellar age of 1.8 Gyr and a metallicity of [Fe/H] = 0.12 dex (metal-rich relative to the Sun). From Earth, CoRoT-7 shines at apparent V-band magnitude 11.728 (faint and requiring research-grade or CCD telescopic photometry) in the Southern celestial hemisphere. The CoRoT-7 system is a multi-planet architecture hosting 3 confirmed worlds, with CoRoT-7 d sharing its stellar neighborhood alongside CoRoT-7 b, CoRoT-7 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: La Silla Observatory · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | CoRoT-7 |
| Spectral Type | G9 V |
| Effective Temp (Teff) | 5,250 K |
| Stellar Radius | 0.8389 R☉ |
| Stellar Mass | 0.9150 M☉ |
| Bolometric Luminosity | 0.48 L☉ |
| Metallicity [Fe/H] | 0.120 dex |
| Stellar Age | 1.800 Gyr |
| Apparent Magnitude | V: 11.728 · G: 11.524 |
| System Architecture | 1 Star, 3 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | — |
| Orbital Period | 8.966 days |
| Orbital Eccentricity (e) | Circular (0.00) |
| Orbital Inclination (i) | — |
| Mean Bulk Density | 1.18 g/cm³ (22.3 km/s vesc) |
| Insolation Flux | — |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 521.500 LY (159.906 pc) |