What is Orbital Velocity?
How fast a planet travels as it orbits around the Sun is called orbital velocity.
Planets that are close to the Sun have large orbital velocities because of Keplerís second law of planetary motion. This means that Mercury, the closest planet to the Sun, is the fastest moving planet in our solar system moving at about 48 km/sec! Earth is orbiting slightly more slowly at a speed of about 30 km/sec and poor Pluto, far from the Sun, travels less than 5 km/sec.
Our Solar System
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Learn more about orbital velocity and experiment with Keplerís second law!
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