Nearly 4 miles down, a remote-controlled sub is surveying a stretch of the Caribbean Sea and Atlantic Ocean that has largely gone unseen by scientists.
And the public is invited along for the ride.
Researchers aboard the National Oceanic and Atmospheric Administration ship Okeanos Explorer are conducting 20 deep sea dives this month, mostly in an area known as the Puerto Rico Trench, which is nearly 50 miles (about 80,465 meters) long and 5.4 miles (about 8,690 meters) deep at its lowest point -- deeper than anywhere in the Atlantic Ocean basin.
The dives are being transmitted to the Office of Ocean Exploration and Research's website, www.oceanexplorer.noaa.gov, and on YouTube (above) where anyone can watch them in near real time.
"We'll be exploring an area of the United States Exclusive Economic Zone that science knows very little about," said Alan Leonardi, director of NOAA's Office of Ocean Exploration and Research, the federal program responsible for coordinating this expedition. "In order to understand and sustainably manage the ocean's resources, we first have to survey what resources exist."
Scientists expect to learn more about an area that is tectonically active, with some seismic hazards such as earthquakes and tsunamis. They also are hoping to get a glimpse of deep-water snapper populations and deep-water corals, as well as geological features such as seamounts and mud volcanoes -- areas that are considered potential hotspots for minerals.
Previous Okeanos Explorer expeditions have come across unknown species, recorded known animals exhibiting never-before-seen behaviors and sighted live animals previously only observed as lifeless specimens.
So far, they have conducted four dives in three different sites and have gone as deep as 2.5 miles (4,000 meters). They have spotted glass sponges, fishes, bamboo corals, anemones, crinoids, sea cucumbers and a ctenophore or comb jelly.
Watching the dives takes plenty of patience. There are long stretches of empty ocean and images of the sandy and rocky ocean floor. But just when you are about to give up, cool creatures -- such as a jellyfish-like animal that glows orange, and a snow-white, shrimp-like crustacean that appeared Monday morning -- come into view.
As part of the expedition, Lt. Brian Kennedy, the expedition's coordinator and a member of NOAA's Commissioned Officers Corps, and the two lead scientists aboard the ship will be leading a Reddit Ask Me Anything, or AMA, session on April 16, from 1 p.m. to 3 p.m. ET.
This story originally appeared on CBSNews.com.