4.Which is roughly equivalent to stacking the world's tallest building on top of itself 4.5 times:
5.The deepest part of the ocean is known as the Challenger Deep, and it is located beneath the Pacific Ocean in the Mariana Trench.
6.And at 6.8 miles below the ocean's surface, the pressure's insane — about 1,000 times higher than up here!
7.Plus, we've only barely begun to scratch that ~surface~ — 95% of the ocean has never even been explored by humans.
(Though, to be fair, most of the ocean looks a lot like this:)
8.So far, only three people have actually spent time so deep underwater. The deepest manned ocean descent was in 1960, when Don Walsh and Jacques Piccard spent almost 20 minutes together in the submarine Trieste 35,797 feet deep at the bottom of Challenger Deep.
9.The third person to venture so deep did so in 2012: Titanic director James Cameron dove in the same place for 3 hours. He reached a depth of 35,755 feet.
10.Which kind of makes sense why, despite our advanced technology, we currently actually have better maps of other planets than of the ocean floor of our own planet.
11.For example, we can map the ocean floor to a maximum resolution of about 5 kilometers, yet we've been able to map most of Venus to a resolution of around 100 meters.
12.Moreover, we've known since 1971 that the largest volcano in the solar system is Olympus Mons on Mars. But we have only known since 2013 that the largest volcano on Earth is the Tamu Massif in the Pacific. 🌋
13.Oh, and here's another insane discovery: We discovered only about three years ago that there is a reservoir of water in the Earth's mantle that is THREE TIMES as large as ALL previously known oceans. Three! Times!
14.The ocean floor is littered with our futile human attempts to cross oceans — based on an estimate by UNESCO, there are about 3 million shipwrecks on ocean floors around the world.
15.And the total value of all sunken treasures is estimated to be $60 billion.
17.Now here's a bit of a mystery: In 1997, a loud, unknown noise (called "the bloop", which you can listen to here) was recorded in the Pacific. For 10 years, no one could explain where it came from.
18.Speaking of mysteries, deep in the water off the coast of Cuba, researchers have found a structure that looks a lot like a sunken city. No one knows for sure whether that's actually the case or if it's just ~random~.
19.Speaking of "things that are randomly found in the water," how about an entirely new continent? Zealandia is a land mass east of Australia, and 94% of it is covered by the Pacific Ocean. But since 2017, the case has been made that it meets all the criteria for being considered as its own continent.
20.In other news, the Pacific Ring of Fire is where 75% of all the planet's volcanoes are located.
21.Now, back to the animals: In some parts of the oceans, there are jellyfish (specifically, lion's mane jellyfish) that can grow up to 120 feet long!
22.And since there aren't really any plants at the deepest parts, all of the living things down there feed on each other, which leads to pretty epic photos like this...