Exoplanet Habitability Score
Calculate the Earth Similarity Index (ESI) for an exoplanet based on radius, density, escape velocity, and surface temperature relative to Earth.
Inputs
Results
Earth Similarity Index
1
Classification
Earth-like
How to Use This Calculator
- Enter Planet Radius (R⊕) relative to Earth — values near 1.0 indicate a rocky, Earth-sized world.
- Enter Planet Density (ρ⊕) relative to Earth's 5,515 kg/m³ to characterize interior composition.
- Enter Escape Velocity (V⊕) relative to Earth's 11.2 km/s — this determines ability to retain an atmosphere.
- Enter Surface Temperature (K): Earth is 288 K; values between 273 K and 373 K allow liquid water.
- Read the Earth Similarity Index (ESI) from 0 to 1 — values above 0.8 are considered Earth-like, and check Water State for habitability clues.
Formula
ESI = ∏(1 - |xᵢ - xᵢ₀| / (xᵢ + xᵢ₀))^(wᵢ/n)Related Calculators
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