Jupiter's massive gravitational force has made it both a wrecking ball and a protector of Earth.

With stunning bands of swirling gas, and its iconic Great Red Spot, Jupiter is a marvel to behold. But this marble-like gas giant—the largest planet in the solar system—has a dramatic past. As a young planet, Jupiter went on a rampage through the solar system. As it sped inward toward the Sun, its massive gravitational force hurled debris into interstellar space, stunting the growth of would-be planets. Earth might have been doomed had Saturn not pulled Jupiter back. But it also shaped life on Earth, delivering comets laden with water—and perhaps even the fateful asteroid that wiped out the dinosaurs. Today, Jupiter resides in the outer solar system, where its gravity bends the paths of asteroids and stokes volcanic activity on its moon Io. But could it one day wreak havoc on its fellow planets again?