How Close Are We to Completely Mapping the Ocean?

We’ve explored the jungles, the deserts, the arctic, even the moon. But one place still remains a mostly uncharted mystery; our oceans. Oceans cover about 70% of Earth’s surface, but we know more about the geography of Mars than we do about what lies on the bottom of the sea. But all that might change. Around the world people are looking to finally reveal the secrets of our deep oceans for both scientific and economic gains. So, how close are we to completely mapping the ocean?

For thousands of years people have taken to the seas with the goal of finding out just how deep our oceans are. This mainly consisted of tying a weight to a long rope and throwing it over the side of a boat. This is actually how we discovered the deepest part of the ocean, the Challenger Deep. Mariana Trench.  Since then we’ve obviously advanced with our technology, and have actually already used satellites to map the entire ocean. Kind of.