0:03 How much of our oceans have we actually
0:05 explored? Because everywhere you seem to
0:07 look, it [music] seems to reference the
0:10 same number, 5%. But is that really
0:13 true? Because the front page of Noah,
0:15 the NASA equivalent for ocean
0:17 exploration, seems to suggest something
0:19 very different. And when I tried to
0:21 track down where the statistic actually
0:23 came from, I stumbled on what might be
0:25 one of the biggest scientific myths of
0:28 the 21st [music] century. In this video,
0:30 you're going to see the actual data,
0:32 maps, and records from organizations
0:34 like Noah and Jebco, the people
0:37 responsible for mapping the seafloor,
0:39 and their findings seem to tell a very
0:41 different story.
0:43 So, where did the 5% statistic come
0:46 from? How much of the ocean do we really
0:49 know? And are there really monsters
0:52 hiding in the deep? The truth is perhaps
0:54 even more interesting than the lie we've
0:56 been told. And to understand where the
0:58 statistic really came from, we need to
1:02 go back almost three decades to 2001,
1:04 a time where the internet was in its
1:06 infancy and where this seed was planted
1:15 The early 2000s were a very different
1:17 time. The [music] internet was slow,
1:19 smaller, and far less connected than it
1:21 is today. And with the turn of the
1:23 century, Noah set a grand goal [music]
1:26 to explore and map the planet's oceans
1:29 for national benefit. And on April 2001,
1:32 Noah Ocean exploration was born. And
1:34 along with it, Noah released a paper
1:36 that would quietly become one of the
1:38 most misunderstood statistics of the
1:41 21st century. Buried in their archives
1:43 was the paper titled The Report of the
1:46 President's Panel for Ocean Exploration.
1:48 On this panel, you had representatives
1:51 from Noah, NASA, the US Navy, and
1:52 leading universities and science
1:55 foundations from all across the country.
1:58 It was a 77page document which outlined
2:01 motivations, hopes, and strategies for
2:04 future exploration. And tucked away in a
2:07 corner, we find a single line. Less than
2:10 5% of the total US exclusive economic
2:13 zone has been mapped in high resolution.
2:15 At first glance, that sounds like a
2:16 statement about how little of the ocean
2:18 we know and how much is still hidden.
2:20 [music] But I want you to pay very close
2:24 attention to this one word, mapped. Not
2:28 explored, not discovered, but mapped.
2:31 And that single word changes everything.
2:33 Because this statement wasn't about all
2:35 of Earth's oceans. It referred
2:36 specifically to the United States
2:39 exclusive economic zone. And that
2:41 distinction matters because the US EEZ
2:44 is enormous. It spans multiple oceans in
2:46 an area larger than many countries
2:49 combined. So as that line spread, it
2:52 quietly lost its original context. US
2:55 waters soon became our oceans and mapped
2:58 became explored. Years later, Noah would
3:00 try to clarify what that number actually
3:04 meant. But by then it was too late. The
3:06 world had already fallen in love with
3:11 the idea. Just 5% of the Earth's only 5%
3:14 of it explores 5% [music]
3:17 5% of the ocean
3:20 remotely operated vehicle% [music]
3:22 that much volume we don't even know
3:25 what's out there. >> 5%.
3:26 >> 5%.
3:28 This wasn't just a number. It came to
3:31 represent hope, curiosity, our fear of
3:33 the unknown. But over time, it also
3:35 became a story that was easier to repeat
3:37 than to question.
3:40 Two decades later, that number hasn't
3:42 changed. We've mapped distant planets,
3:43 digitized nearly every part of our
3:45 lives, and are now training machines to
3:48 think alongside us. And yet, that number
3:50 stayed at 5%, almost like our
3:53 exploration of the ocean has somehow
3:56 stayed frozen in time. Over the next 20
3:58 years, Noah released paper after paper
4:01 detailing expeditions, discoveries, and
4:04 efforts to really understand our oceans.
4:06 The work was happening quietly,
4:08 relentlessly, but the story the world
4:12 told itself stayed the same. Today,
4:14 we're going to tell a different story.
4:16 One that does justice to the explorers
4:19 and reveals how much of the ocean we
4:22 truly know.
4:23 To do this, we need to first look at
4:26 what exploration really means. When Noah
4:28 talks about exploring the ocean, they're
4:30 actually talking about three very
4:32 different things. The first is satellite
4:34 mapping. From space, satellites don't
4:36 see the seafloor directly. They read
4:39 tiny changes in the ocean surface caused
4:41 by gravity. And from that, scientists
4:43 can infer the rough shape of the ocean
4:45 floor. This gives us a global
4:47 lowresolution map, enough to reveal
4:49 massive features like ridges, trenches,
4:51 and underwater mountains. but not enough
4:54 to show fine detail. In fact, using this
4:55 method, the entire ocean has already
4:58 been mapped since the early 2000s, and
4:59 it's what made tools like Google Earth
5:01 possible in the first place when it
5:04 launched in 2004. And even at this
5:06 resolution, scientists were able to
5:08 utilize updated satellite data to
5:10 identify around 19,000 previously
5:14 unknown underwater volcanoes in 2023.
5:16 The second layer is sonar mapping.
5:18 Unlike satellites, sonar mapping is
5:20 carried out by ships that traverse the
5:22 ocean, sending sound waves to the
5:24 seafloor and measuring what comes back.
5:26 For comparison, it allows us to map the
5:28 deep ocean in high definition and
5:30 provides us with real detail on the
5:33 structure of the seabed itself. And this
5:35 was what the original 5% statistic was
5:38 actually referring to. That 5% of US
5:40 waters were mapped in high definition as
5:44 of 2001. And that number most certainly
5:46 hasn't stayed the same in the last 20
5:48 years. While sona mapping was slow to
5:50 begin with, the real turning point came
5:52 with the introduction of the Noah ship
5:55 Okianis Explorer in [music] 2008. This
5:56 was a state-of-the-art vessel equipped
5:58 with multi-beam sona technology that
6:00 would operate continuously to map the
6:03 seafloor to a depth of 6,000 m. This
6:05 provided us with some of the first
6:06 highdefinition maps of previously
6:09 unexplored areas. Ridges emitting
6:11 unexpected heat, geological structures
6:13 unlike anything we had ever [music] seen
6:15 before, and it gave us the first glimpse
6:18 at what was really in our oceans.
6:20 By 2010, more investment was placed into
6:22 AUVs, autonomous vehicles similar to the
6:24 exploration rover NASA uses on [music]
6:26 Mars with an unprecedented crush depth
6:28 that not only supported mapping, but
6:30 could also provide detailed images of
6:32 objects on the seafloor. were able to
6:34 trace slopes, vents, and fracture zones
6:36 in three dimensions. And this gave us
6:38 insight into potential ecosystems that
6:41 supported life. And in 2017, one of the
6:43 most ambitious projects was created,
6:46 Seabed 2030. This was a collaboration
6:48 between governments, research
6:50 institutions, philanthropy, and
6:52 non-government organizations all across
6:54 the world with one single goal to
6:56 achieve a complete map of the entire
7:00 seabed by 2030. And with it mapping
7:02 proceeded at the unprecedented rate. In
7:06 2017 the global mapped figure was 6%. In
7:10 2020 that figure grew to 19% and as of
7:13 June 2025 that figure sits at 27.3%. [music]
7:15 [music]
7:17 And for US waters that figure sits even
7:19 higher at 52%.
7:21 So by the original definition that gave
7:24 us the 5% statistic, we've already
7:26 explored far more than we're often led
7:29 to believe. And this leads us to the
7:31 third and most important layer. The one
7:33 people usually mean when they say
7:36 explored, which is direct exploration.
7:38 This is from things like human dives,
7:40 submersibles, or ROVs sending back video
7:43 from places no one had ever seen. And as
7:45 our exploration continued in the
7:47 Twilight Zone, we discovered a world
7:49 very different from what we expected.
7:51 For years, our main way to determine
7:53 what really lived down there relied on
7:55 nets, which destroyed soft-bodied
7:57 organisms and bioscience towards fish.
7:59 But it turned out the largest habitat on
8:01 Earth was in fact teameming with
8:02 gelatinous life and tiny [music]
8:05 crustations like anthropods. As we
8:07 descended deeper, exploration revealed
8:09 brine pools, underwater lakes that
8:11 killed on contact, and whale carcasses
8:13 that formed entire [music] ecosystems
8:16 that feel deep sea organisms for years
8:18 at a time. And for the first time, we
8:20 came across ecosystems that thrive in
8:22 total darkness around hydrothermal
8:25 vents. These organisms didn't survive on
8:28 sunlight, but on chemosynthesis. And
8:30 this reshaped not just how we understood
8:32 life in the deep ocean, but the very
8:34 limits of life itself. And deepest
8:37 still, almost 4,000 m below sea level,
8:39 we came across entire coral forests
8:41 growing without light, with some species
8:44 found to be over 4,000 years old. Much
8:45 like rings in the tree trunk, their
8:48 skeletons act as climate databases and
8:50 give us a glimpse into past ocean
8:53 conditions. So yes, exploration of our
8:56 own oceans have never stopped. And with
8:59 all this in mind, how much of our deep
9:01 ocean have we actually explored [music]
9:03 where we've seen the deep sea floor
9:07 directly with our own eyes? The truth is
9:09 less than a thousandth of a percent. Far
9:11 from the numbers that people often
9:13 claim. And while that number may sound
9:15 shocking, it's because direct ocean
9:18 exploration is ridiculously expensive. A
9:20 single deep sea expedition can cost tens
9:22 of millions of dollars, requiring a full
9:24 crew and weeks of planning just to
9:27 glimpse a few square kilm of sea floor.
9:29 But this does not mean we know nothing
9:31 about the ocean. Far from it. It means
9:33 we've learned about our oceans in a very
9:36 different way than most people imagine.
9:38 In some ways, we've explored our oceans
9:40 the same way astronomers explore the
9:42 universe. by understanding patterns at
9:44 scale than choosing where to look
9:46 closer. But that raises an obvious
9:49 question. If we've directly explored so
9:51 little, does that mean almost anything
9:55 could be hiding down there?
9:56 While it may be tempting to imagine that
9:59 in all that unexplored space, there
10:01 could be unknown giants lurking in the
10:03 deep, I want to provide a more realistic
10:06 outlook. Because large life, especially
10:08 apex predators, require enormous amounts
10:10 of energy to survive. They can't exist
10:12 quietly without reshaping entire
10:15 ecosystems around them and are often the
10:17 most obvious to detect, whether it's
10:19 from their own remains or distinctive
10:21 bite marks and scars from the bodies of
10:24 their prey. And it's why we're able to
10:26 be aware of things like the giant squid
10:27 years before we actually saw live
10:29 footage of one. On top of that, we can
10:31 learn a lot from mapping about our deep
10:33 sea, like the types of environmental
10:35 pressures and what types of life these
10:37 habitats can support. And scientists are
10:39 able to combine their understanding of
10:41 different biomes with something called
10:43 environmental DNA. Things like skin
10:45 cells and feces shed by organisms into
10:47 their environment, which allows us to
10:49 learn about creatures without ever
10:51 having to see them. It's the same reason
10:53 why we don't need to have explored 100%
10:55 of the Amazon rainforest to know that
10:57 elephants or rhinos aren't hiding in
10:59 there. So, while the deep ocean is still
11:01 full of mystery, it's unlikely to be
11:03 hiding unknown colossal giants of the
11:06 kind people often imagine. But that
11:07 doesn't mean it isn't hiding something
11:10 far more interesting. Because the ocean
11:12 is full of more subtle, smaller
11:14 creatures, and scientists estimate that
11:17 between 70 to 90% of marine species have
11:19 yet to be discovered, even before
11:22 counting microorganisms. That's roughly
11:24 700,000 to a million species still
11:27 unknown to us. Which is exactly what
11:29 makes projects like Seabed 2030 so
11:30 exciting. With more and more
11:32 organizations contributing to global
11:34 mapping efforts, our knowledge of the
11:37 ocean is accelerating. We now have
11:38 autonomous robots that drift through the
11:41 deep for months at a time, collecting
11:43 things like mapping data, live footage,
11:45 and Edna. And scientists are working
11:47 tirelessly all around the world to
11:50 interpret their findings. So, modern
11:52 discovery doesn't happen all at once. It
11:54 looks like thousands of small, quiet
11:57 discoveries adding up over time. a new
12:00 species here, a new biome there, maybe
12:02 some fragments of DNA on the seafloor.
12:04 And all of it continues to refine what
12:07 we really know. And the most exciting
12:08 part is that by understanding our
12:11 oceans, we also uncover our planet's
12:13 history and the true limits of the
12:15 environments life can survive in. And
12:17 [music] those insights may one day help
12:19 us recognize where life could exist
12:21 elsewhere, beneath layers of ice, [music]
12:22 [music]
12:24 even on other worlds.
12:26 So, if so much work has been done
12:28 continuously, why has the myth persisted
12:32 for so long? Part of it is simple. We're
12:34 naturally drawn to mystery, and it
12:35 captures our attention in a way
12:37 scientific accuracy often doesn't.
12:39 [music] And modern media doesn't reward
12:42 precision or careful nuance, it rewards
12:45 spectacle. And once an idea like this
12:47 takes hold, once it's repeated often
12:49 enough, it quietly becomes something
12:52 people accept as true, even when the
12:55 reality was never far from reach. That
12:57 doesn't mean that those who repeated the
12:58 statistic were malicious. They were
13:01 probably just like you and I, curious,
13:03 imaginative, and drawn to the idea that
13:05 there's still something vast and
13:08 unknowable beneath the surface. A world
13:10 where wonder feels infinite and where
13:12 mystery will never run out. But the
13:14 ocean doesn't need exaggeration to be
13:17 fascinating. It's already full of life
13:19 adapting in ways we're still beginning
13:22 to understand. And as tempting as it is
13:24 to imagine sea monsters and dress the
13:26 ocean up as something it was never meant
13:30 to be, I believe the truth is always
