The ocean covers over 70% of the Earth's surface, but most of it remains unexplored. In fact, we know more about the surface of Mars than we do about the deep ocean. This is due to a number of factors, including the difficulty of reaching the deep ocean, the harsh conditions there, and the lack of technology to explore it.

However, in recent years, there have been significant advances in ocean exploration technology. This has allowed us to learn more about the deep ocean and its inhabitants. For example, we now know that the deep ocean is home to a vast array of creatures, including giant squid, hydrothermal vent communities, and deep-sea corals.

We are also learning more about the importance of the deep ocean to the global ecosystem. For example, the deep ocean plays a role in regulating the Earth's climate and provides a habitat for a variety of marine life.

As we continue to explore the deep ocean, we will learn more about its importance and its role in the global ecosystem. This knowledge will help us to better understand and protect our planet.

Here are some specific examples of how little of the ocean has been explored:

* Of the ocean's estimated 1 billion species, only about 1% have been identified and described.

* The deepest part of the ocean, the Mariana Trench, is over 11,000 meters deep. Only a handful of people have ever been to the bottom of the Mariana Trench.

* Most of the ocean floor is covered in darkness. Sunlight only penetrates the first few hundred meters of the ocean.

* The ocean is home to a variety of extreme environments, including hydrothermal vents, cold seeps, and deep-sea trenches. These environments are difficult to study and are only beginning to be understood.

As we continue to explore the ocean, we will learn more about its importance and its role in the global ecosystem. This knowledge will help us to better understand and protect our planet.