The ocean known for being the deepest is the Pacific Ocean. It covers more than 63 million square miles and contains the Mariana Trench, which reaches depths of approximately 36,000 feet. The Pacific Ocean plays a critical role in Earth's climate and ecosystem, influencing weather patterns and supporting a diverse range of marine life. Its vastness and depth present opportunities for exploration and research, making it a focal point for oceanographers and environmental scientists studying oceanic processes and biodiversity.