12 Mar 2018 - The Earth is an ocean planet—more than 70 percent of the surface is covered by seawater. But despite being such an essential part of life, the deepest parts of the world's oceans are still largely unexplored. According to the American Museum of Natural History in New York, merely 10 to 15 percent of the seafloor has been mapped with accuracy, which means we know less about the seafloor than the surface of Mars.
But the state of sea exploration is changing fast. The dark, high-pressure conditions of the ocean depths that once made research there impossible are now being explored with cutting-edge technology. That new tech and the discoveries to come from it are the focus of a new exhibition at the American Museum of Natural History called Unseen Oceans. As museum curator John Sparks said at a press preview, the goal of the exhibition is to show visitors "how little we know, and to tell them how much we're learning so rapidly with technology."
Here are some of the technologies featured in the exhibition, which opens March 12.
1. FLUORESCENCE-DETECTING CAMERAS TO FIND GLOWING FISH
One of the biggest recent discoveries made in the field of deep ocean exploration is the proliferation of biofluorescence in the darkest parts of the sea. Realms that look pitch black to human eyes are actually filled with more than 250 species of fish glowing in red, orange, and green hues. One of these species is the catshark, which fluoresces green in the dim blue light that reaches the sea floor. To detect this effect, researchers built a camera that filters out certain wavelengths of light like the shark's eye does. (This is how the sharks see each other in the darkness.) Combined with artificial blue light to enhance the fluorescent color, this equipment allows scientists to record the light show.
2. AN ALL-IN-ONE ECHOSOUNDER, SPEAKER, AND MICROPHONE THAT "SPEAKS WHALE"
Listening to whales vocalize tells us a lot about the way they live and interact, but this is difficult to do when a species spends most of its time in the deep ocean. In order to eavesdrop on beaked whales, scientists needed to fit sophisticated acoustic equipment into a submersible built to explore high-pressure environments. Enter the Deep Ocean REMUS Echosounder, or DOR-E. (REMUS stands for "Remote Environmental Monitoring UnitS.") Developed by marine scientist Kelly Benoit-Bird and her team at the Monterey Bay Aquarium Research Institute, the autonomous underwater vehicle can reach depths up to 1970 feet and has enough battery life to record a day's worth of deep-sea audio. The device was named for Finding Nemo's Dory because it "speaks whale," according to Unseen Oceans.
3. SOFT GRIPPERS FOR GENTLY COLLECTING SPECIMENS
Collecting specimens at the bottom of the ocean isn't as simple as collecting them on land; researchers can't just step out of their submersible to pick up a mollusk from the seabed. The only way to retrieve a sample at such depths is with a machine. When these machines are designed to be bulky and rigid to withstand the intense water pressure around them, they can end up crushing the specimen before scientists have the chance to study it. So-called soft grippers are a clever alternative. Memory foam evenly distributes the force around the creature being handled, and Kevlar lace keeps the fingers from spreading when they inflate with water. Even with its squishy construction, the mechanism is sturdy enough to work at depths reaching 1000 feet.
4. AFFORDABLE AQUATIC DRONES TO EXPLORE HIGH-PRESSURE DEPTHS
A remotely operated vehicle (ROV) can explore the tight, crushing pockets of the ocean that human divers can't reach. This technology is often costly and limited to research teams with big budgets. A new company called OpenROV aims to make underwater drones more accessible to everyday explorers. Their signature ROV, Trident, starts at just $1500.
5. SATELLITE IMAGING FOR MAPPING THE OCEAN FLOOR
Sometimes the easiest way for scientists to get a view of the bottom of the ocean is by sending equipment to space. Satellites in orbit can estimate measurements of the peaks and valleys shaping the seabed by beaming radar pulses towards Earth and calculating the time it takes for them to bounce back. While this method doesn't provide a terribly accurate map of the ocean floor, it can be used to gauge depths in even the most remote areas.
6. SWARMS OF MINI ROBOTS THAT BOB AND FLOAT LIKE PLANKTON
Autonomous undersea robots come in all shapes and sizes. Mini-autonomous underwater explorers, or m-AUEs, developed by Scripps oceanographer Jules Jaffe are meant to be deployed in large groups or "swarms." The grapefruit-sized devices act like plankton, bobbing at a constant depth in the ocean and measuring factors like water temperature. By studying the underwater explorers, scientists hope to better understand how plankton, major contributors of the Earth's oxygen, thrive and travel through the sea.
7. SUCTION-CUP "TAGS" FOR STUDYING JELLIES
This technology is so new, it hasn't hit the water yet. Once it's ocean-ready, researchers plan to attach the miniature suction cups to the bells of jellies. The device automatically measures a jelly's movements and ocean chemistry as the animal swims around. Eventually the jelly regenerates the top layer of its bell, shedding the tag and moving on unharmed. Once detached, the tag floats to the water's surface where it alerts scientists to its location via a VHF antenna and green reflective tape.