It is cold and dark. Creatures here have adapted to live and thrive in this environment, but not us. Once you pass the threshold of the aptly-named twilight zone, around 650 feet, there isn’t enough light to fuel photosynthesis. For every 33 feet of depth gained, the pressure increases by 14.5 pounds per square inch or psi; at a certain point, most organisms with gas-filled spaces, like our human lungs, would be crushed. As you continue to travel farther down, the weight of all the water above and around you presses in, making it impossible to pass a certain point without specialized technology. Most humans will never experience these mysterious depths firsthand. With the aid of submersibles, only three people have ever ventured to the deepest point in the ocean, the Mariana Trench, seven miles below the surface. The challenges of reaching this hadalpelagic zone make it one of the least studied locations on Earth.
I’ve talked to experts, visited their labs and research centers, and watched them at work–often under challenging circumstances. I’ve been to sea and shared the joys of science and discovery alongside bouts of seasickness, equipment malfunctions, and precious time away from loved ones. Few things I’ve experienced in 46 years on this planet compare to going someplace no human has ever gone before, to seeing this other world that exists right here at home.
Until we get out there and start poking around, we have no idea what we might find, but, according to NOAA, “More than eighty percent of our ocean is unmapped, unobserved, and unexplored.
I’m a writer and an educator. I’m also lucky to be able to say this: I am an ocean explorer.
Having spent the last two summers at sea, observing a wildlife survey in National Marine Sanctuaries on the NOAA Ship Bell M. Shimada and supporting robotic exploration of the deep sea aboard Robert Ballard’s Exploration Vessel (E/V) Nautilus, this is what I’ve learned: the Earth’s ocean is vast with many secrets waiting to be discovered.
Just a few months ago, in October, while exploring off the coast of California near Monterey, the E/V Nautilus team was moving their robotic explorer or ROV (which stands for remotely operated vehicle) down the flank of a seamount and out of nowhere they happened upon a brooding site with thousands of octopuses in shimmering water that indicated hydrothermal activity of some sort. No one has ever seen anything on this scale before. This real-life octopus garden is just one example of the discoveries waiting for us in our ocean.
To get a sense of scale of the discoveries still possible, consider the 2010 Census for Marine life. It took a decade to complete and was conducted by 2,700 scientists from over 80 countries, on 540 scientific expeditions, at a cost of $650 million dollars, U.S. They identified over 6,000 potential new species and published more than 2,600 research papers. The project shed light on a variety of ocean science research–from a white shark cafe in the open ocean to enormous microbial mats, “ranked among Earth’s largest masses of life.”
The census represents a monumental bit of discovery. Yet scientists, like Chris German from Woods Hole Oceanographic Institute (WHOI), think we’ve only scratched the surface. While off the coast of Hawaii last summer, German pointed to the Pacific Ocean, noting that it covers half of the planet and is “woefully unexplored.” He’s been studying hydrothermal vent systems just along the mid-ocean ridge for 30 years. The mid-ocean ridge is a ribbon-like mountain range that runs through the entire global ocean; it is about ten miles wide and 37 thousand miles long.
German estimates that the oceanic community has made discoveries at a rate of one new species every two weeks during his 30-year career. Even exploring as fast as they can go, they’ve only been able to explore about 20 percent of the mid-ocean ridge in three decades. He and his colleagues see opportunities to expand our capabilities here on Earth with emerging technologies in development for future space missions. Essentially, our drive to reach outer space and other ocean worlds will unearth much in unexplored regions of our ocean.
The oceanic and space communities have a great deal to offer each other–from technology development to protocols and training for remote work in extreme environments. In fact, scientists like Julie Huber believe it is time for the oceanic community to be more like NASA. Huber is an expert in marine chemistry and geochemistry at WHOI. Her work examines microbial communities in the deep ocean and, in the not-so-distant future, on other planets.
Huber argues: if NASA can land a scientific laboratory on Mars, then we should be able to do the same here on Earth. Sending scientific vessels to sea or space is no small feat. Ship time and space launches are costly and hard to come by. However, advances in marine robotics, such as Monterey Bay Aquarium Research Institute’s (MBARI) environmental sample processor (ESP) make it possible to do much more with less. When loaded onto an autonomous underwater vehicle, the ESP is a lab-in-a-can, collecting samples and processing them in situ for near real-time oceanographic monitoring. Huber advocates for developing new technologies, similar to MBARI’s ESP, that would allow for analysis of microbes in extreme environments like the deep ocean.
Huber is part of a program called NASA SUBSEA, which stands for Systematic Underwater Biogeochemical Science and Exploration Analog. The SUBSEA team members come from NASA, NOAA, the Ocean Exploration Trust, and several academic centers, including WHOI and Idaho State University.
In August and September, I served as the lead science communication fellow on board the E/V Nautilus during the NASA SUBSEA expedition to the Lōi`hi Seamount off the coast of Hawaii. The SUBSEA team is planning for future remote deep-space exploration of Europa and Saturn’s moon Enceladus as well as crewed missions to Mars and our own moon.
Robotic dives at Lōi`hi offered the opportunity to practice and develop protocols for future missions because today’s ocean explorers work remotely, using tools and methods that will serve space exploration. Someday, when we reach distant ocean worlds, we will deploy robots and explore from the safety of a command center here on Earth, a spaceship, or some other location like a base on the moon or an asteroid.
In order to prepare for those future missions, NASA and their partners gathered a science team at the Inner Space Center at University of Rhode Island’s Graduate School of Oceanography. This team remotely directed our operations on the E/V Nautilus while we were in Hawaii, serving as “mission control” for the expedition. Experiencing time-delays and technical difficulties will enable NASA and their partners to be better prepared for the challenges of deep space exploration.
Conditions at Lōi`hi, which is an active underwater volcano, are similar to what scientists believe exist on these other moons in our solar system.Lōi`hi was selected because the lower temperatures (about 390 degrees F) at these hydrothermal vent sites, called white smokers, are similar to temperatures detected by the Cassini spacecraft at Europa. Using ROVs, we collected rock and water samples so astrobiologists in Huber’s lab at WHOI and geologists from Idaho State could determine what sorts of rock and water interactions are taking place.
In places where sunlight doesn’t reach, there is no photosynthesis for food production. So, organisms like the microbes we observed and collected at Lōi`hi are make a living off of chemical reactions. Scientists are studying these reactions in order to model what could be happening on other planets.
To Darlene Lim, NASA Geobiologist and principal investigator for the SUBSEA program, the impetus to explore is an insatiable curiosity about what might be waiting out there. Lim has spent the better part of her career running teams and research in extreme environments on Earth, using them as analogs for future exploration elsewhere in our solar system and beyond.
“We have a sample size of one,” said Lim. “We know that this planet is habitable; we know it is full of life, but what else is out there?”
She adds that we have, at our fingertips, the opportunity to go and in situ understand whether or not life is beyond this planet in our solar system. She smiles and becomes animated when she talks about exploration, making her enthusiasm highly contagious. It’s hard not to get excited about answering questions humans have been asking for all of our brief history on Earth. “What an exciting endeavor that I think we should to take the opportunity to stretch out and accomplish,” said Lim.
But what will it be like when we actually get to one of these remote, distant places in our solar system? Will we find life?
Imagine you’re flying over an ocean world, not Earth but another. Maybe this is Europa, one of Jupiter’s moons. It is cold and inhospitable. But, scientists know there is an iron core, a rocky mantle, and a salty ocean. How do they know this?
Take a look at the composite image below. There are plumes of water vapor at about 7 o’clock. To identify these plumes, scientists used Hubble’s imaging spectrograph, an instrument which acts like a prism revealing a sort of wavelength fingerprint of the object being observed; this fingerprint makes identification possible. Using this instrument, they were able to capture the silhouette of Europa as it passed in front of Jupiter and identify these plumes of water vapor, rising over 62 miles above the surface. These data aligned with previous observations from Cassini flyovers of Europa and they indicate the presence of an ocean and geologic activity worthy of exploration.
When we do get to Europa, there will be no humans on the mission. In the coming years, we are going to overcome incredible engineering obstacles in order to land robotic explorers on a distant icy moon, over 390 million miles from home.
According to German, experts think we can get there by 2033. Then, once we’ve landed on the surface of Europa, it will take another two years to drill ten to fifteen miles through the ice in order to eventually make our way to the ocean floor and transmit images home to Earth–images that these scientists hope will include hydrothermal vents and microbial mats.
Lim said it generally takes 18 to 24 months to be able to draw meaningful conclusions from the fieldwork that took place at Lōi`hi, but she says everything is on track. This means I can’t really tell you exactly what was learned last summer, just yet, but I can attempt to convey why the work is so cool. While we were still at sea, I asked Lim and German why would we should travel 390 million miles to find tiny microbes.
“Any time that humanity has extended itself in that way, along comes other developments. Think social developments–the way we think about ourselves, we organize ourselves, what we think is palatable in terms of the way we treat other people,” said Lim. “It kind of comes hand-in-hand with the ability to think about what is beyond us.”
To German, 390 million miles, when considered alongside the vastness of space, isn’t really that far to travel at all.
“Rather perversely, what’s really exciting about it is only having to go 390 million miles for what we can do is ridiculously close to home,” said German. “And that’s completely new thing in the last decade.”
He goes on to explain that when we thought of looking for life elsewhere in the universe, we traditionally thought about looking for planets with liquid water on the surface and the kind of life forms that we understand from photosynthesis, the dominant form of life on our own planet.
To German, the current generation of ocean exploration work has revolutionized our view of what it takes to make planet habitable. The discovery of seafloor hot springs and cold seeps like those found along the California Borderlands have offered what German describes as a “panoply of different kinds of habitable environments that are often independent of sunlight.”
He’s quick to point out that on our own planet, we know that single-celled life was the only thing in town for the first two to three billion years of our history. “If an alien had ever come searching for life on our planet, there’s a two-to-one chance that all they would have found was an ocean full of microbial life and a barren landscape,” said German.
German believes that we could find microbial life in one or more of about half a dozen candidates in our solar system, in places with an ocean with geologic activity like Europa. German adds with zeal, “It’s closer to home than human-made robots have already been. We don’t even have to go to the limits of human ambition!”
During the 2019 expedition season, the SUBSEA team will be returning to the E/V Nautilus and diving at the Gorda Ridge in late May and early June–you can follow along from home by watching the live-streamed dives. The ridge is another volcanically active area off the coast of Southern Oregon and Northern California with temperatures and conditions similar to Lōi`hi.
The team will do much of the same science–looking at how the rock and water interactions support microbial communities–but they will also introduce communication breaks to simulate planned and unplanned communication drop offs.
It will be wonderful to see what we learn from this work and subsequent projects. To me, what is truly exciting is that ocean exploration here on Earth will eventually give us the tools to visit other ocean worlds. In return, our drive to explore the universe will allow us to better understand our home planet – to locate majestic underwater mountains, identify new medicinal resources, and discover sea creatures that defy imagination. And, after spending time with scientists like Lim, German and the SUBSEA team, I see that the opportunity to extend ourselves beyond the boundaries of what we currently understand about science, technology, engineering, and even ourselves makes a more-than-compelling case for exploration.
Until we get out there and start poking around, who knows what we will find?
Take to the high seas: microbiology labs below the ocean surface by Julie Huber and Christina Preston