Jupiter, with its massive size and strong gravitational pull, plays a significant role in the solar system's dynamics, particularly in shielding Earth from potential comet and asteroid impacts. Its gravity acts like a cosmic vacuum cleaner, attracting or deflecting comets and asteroids that might otherwise come closer to the inner solar system, including Earth. However, it's also important to note that Jupiter's gravity can sometimes have the opposite effect, by redirecting objects towards the inner solar system. Overall, its role is complex but largely beneficial in reducing the number of space objects that could pose a threat to Earth.