Only about 20% of the ocean’s depths has been mapped by humans. Here’s what we do — and don’t — know about the deep seas and why studying them is so risky.

There is, however, currently an effort underway to create a definitive map of the ocean floor, called Seabed 2030. Still, there are huge gaps in what’s known of the deep sea.

It would take nearly 300 years — in the aftermath of the Titanic disaster — before sonar technology began to offer scientists a clearer picture of what lies in the ocean's depths.A major step ...

It would take nearly 300 years — in the aftermath of the Titanic disaster — before sonar technology began to offer scientists a clearer picture of what lies in the ocean's depths.A major step ...

There is, however, currently an effort underway to create a definitive map of the ocean floor, called Seabed 2030. Still, there are huge gaps in what’s known of the deep sea.

It would take nearly 300 years — in the aftermath of the Titanic disaster — before sonar technology began to offer scientists a clearer picture of what lies in the ocean's depths.A major step ...

What we know about the ocean’s depths — and why it’s so risky to explore it. ... currently an effort underway to create a definitive map of the ocean floor, called Seabed 2030.

What we know about the ocean’s depths — and why it’s so risky to explore it. ... currently an effort underway to create a definitive map of the ocean floor, called Seabed 2030.

We're not far from where the expedition launched on Sunday. It was an hour and 45 minutes into the dive that the vessel lost contact with its mother ship. It's been lost and silent since then. Now ...

We're not far from where the expedition launched on Sunday. It was an hour and 45 minutes into the dive that the vessel lost contact with its mother ship. It's been lost and silent since then. Now ...