Ross 508 b
Astrophysical Synthesis & Habitability Characterization
Ross 508 b is a confirmed super-earth exoplanet orbiting the star Ross 508, located approximately 36.6 light-years (11.21 parsecs) from the Solar System. First announced in 2022 by Subaru Telescope using the Radial Velocity detection technique (measuring periodic Doppler reflex motion in the host star's spectrum), this world measures 1.83 Earth radii and has a measured mass of 4 Earth masses. Combining its mass and radius yields a mean bulk density of 3.6 g/cm³ (an intermediate density indicative of a deep water-ice mantle or dense volatile envelope), a surface gravity of 1.19 g⊕ (11.67 m/s²), and an escape velocity of 16.5 km/s.
In its orbital architecture around Ross 508, Ross 508 b completes one full revolution every 10.77 Earth days at a semi-major axis of 0.05366 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 54.2 km/s (compared to Earth's 29.8 km/s). The planet follows a highly eccentric trajectory (e = 0.33, swinging from 0.036 AU at periapsis out to 0.0714 AU at apoapsis), pointing to past dynamical scattering or secular gravitational perturbations.
✓ Classified as a Temperate Habitable Zone Candidate.
With an estimated equilibrium temperature of 294 K (+21°C / +70°F) and an incident stellar irradiance of 1.25 S⊕ (~1,696 W/m²), Ross 508 b orbits within the empirical circumstellar habitable zone where a rocky surface under sufficient atmospheric pressure can maintain liquid surface water.
The host star Ross 508 is classified as a low-mass red dwarf of spectral type M4.5 V with an effective photospheric temperature of 3,071 K, a radius of 0.2113 R☉, a mass of 0.1774 M☉, an estimated bolometric luminosity of 0.00356 L☉. Stellar evolution modeling indicates a metallicity of [Fe/H] = -0.2 dex (metal-poor relative to the Sun). From Earth, Ross 508 shines at apparent V-band magnitude 14.18 (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: Subaru Telescope · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | Ross 508 |
| Spectral Type | M4.5 V |
| Effective Temp (Teff) | 3,071 K |
| Stellar Radius | 0.2113 R☉ |
| Stellar Mass | 0.1774 M☉ |
| Bolometric Luminosity | 0.00356 L☉ |
| Metallicity [Fe/H] | -0.200 dex |
| Stellar Age | — |
| Apparent Magnitude | V: 14.180 · G: 12.207 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.053660 AU |
| Orbital Period | 10.77 days |
| Mean Orbital Velocity | 54.2 km/s |
| Orbital Eccentricity (e) | 0.33000 |
| Orbital Inclination (i) | — |
| Mean Bulk Density | 3.6 g/cm³ (16.5 km/s vesc) |
| Insolation Flux | 1.2464 S⊕ (~1,696 W/m²) |
| Habitable Zone Status | ★ Temperate Zone |
| Celestial Distance | 36.600 LY (11.210 pc) |