Compare calculators
Both calculators run independently — change the inputs on either side to compare results.
Astronomy
Orbital Velocity Calculator
Compute the orbital velocity around a central body using v = √(GM/r) × √(1+e), an approximation that scales the circular-orbit speed by the eccentricity. Useful for first-order estimates of satellite velocities, planetary orbital speeds, and binary star systems.
Astronomy
Stellar Luminosity Calculator
Compute a star's luminosity in solar units (L☉) from its radius and surface temperature via the Stefan-Boltzmann law. The fundamental relationship between stellar size, temperature, and total energy output — and the basis of the Hertzsprung-Russell diagram.
Key differences
| Orbital Velocity Calculator | Stellar Luminosity Calculator | |
|---|---|---|
| Category | Astronomy | Astronomy |
| Inputs required | 3 | 2 |
| Result | Orbital Velocity (m/s) | Stellar Luminosity (L☉) |
| What it does | Compute the orbital velocity around a central body using v = √(GM/r) × √(1+e), an approximation that scales the circular-orbit speed by the eccentricity. Useful for first-order estimates of satellite velocities, planetary orbital speeds, and binary star systems. | Compute a star's luminosity in solar units (L☉) from its radius and surface temperature via the Stefan-Boltzmann law. The fundamental relationship between stellar size, temperature, and total energy output — and the basis of the Hertzsprung-Russell diagram. |