Here's why:
* Kepler's Third Law: This law states that the square of a planet's orbital period is proportional to the cube of its average distance from the sun.
* Distance: Gas giants like Jupiter, Saturn, Uranus, and Neptune are much farther from the sun than Earth.
* Orbital Period: Because of their greater distance, they take much longer to complete one orbit around the sun.
Here's a simple comparison:
* Earth's orbital period: 365.25 days
* Jupiter's orbital period: 11.86 Earth years
* Saturn's orbital period: 29.46 Earth years
* Uranus's orbital period: 84.01 Earth years
* Neptune's orbital period: 164.79 Earth years
So, while the gas giants are massive, their farther distance from the sun means they move slower in their orbits.