Why does the ISS travel so fast?

At its low orbital altitude, Earth's gravity is still nearly full strength, so the ISS must travel at roughly 7.7 km/s to maintain a stable orbit without falling back to Earth.

Orbital Velocity Calculator

Calculate the velocity an object needs to maintain a stable circular orbit around a celestial body at a given orbital radius.

Inputs

Results

Orbital Velocity: 7,672.5 m/s

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Formula

v = √(GM / r)

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Astrophysics and Energy: Orbits, Gravity, and Photons

Orbital velocity, gravitational force, photon energy, and spring potential energy — four calculations spanning orbital mechanics and energy storage.

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