Explore the intriguing possibility of a hidden massive planet in our solar system in this 15-minute educational video. Delve into the evidence suggesting the existence of Planet 9, including its potential effects on Uranus, Neptune, and Trans-Neptunian objects. Learn about the challenges in detecting such a distant celestial body and examine various theories on its origin, composition, and appearance. Investigate why astronomers believe this elusive planet might exist, its possible characteristics, and its implications for our understanding of the solar system. Consider alternative explanations for observed orbital anomalies and gain insights into ongoing astronomical research and debates surrounding this fascinating topic.