Ocean exploration is a tricky, risky business since humans can’t naturally survive under the ocean. Ocean explorers are constantly inventing new tools to help them dive deep into the sea. Over the last few hundred years or so, and especially in the last few decades, we humans have come up with all kinds of new ways to study the ocean. Even so, the ocean remains largely unexplored. It’s huge, cold, salty, and deep. Ocean exploration helps us understand our planet, and may help us solve the mystery of how life started on Earth.