Have you ever tried snorkeling? It’s a fun way to explore the ocean and see all kinds of amazing sea creatures, especially around coral reefs. When you snorkel, you stay near the surface of the water because the snorkel helps you breathe. But have you ever wondered how deep the ocean really is?
For a long time, people didn’t know how deep the ocean was. Sailors would drop an anchor to stop their boats, but sometimes the anchor wouldn’t reach the bottom. This made them curious about just how deep the ocean could be.
At first, sailors tried using long ropes with weights to measure the ocean’s depth. They would drop the rope until it hit the bottom and then measure how much rope they used. But in some places, even three or four miles of rope wasn’t enough!
Eventually, scientists found a better way to measure the ocean’s depth using something called sonar. Sonar uses sound waves to find out how deep the ocean is. It’s similar to how bats use sound to navigate in the dark. Boats send sound waves down to the ocean floor and listen for the echoes that bounce back. By timing how long it takes for the sound to return, scientists can calculate the depth of the ocean.
With sonar, scientists have created detailed maps of the ocean floor. They discovered huge underwater mountains and deep canyons called trenches. One of the most famous trenches is the Mariana Trench in the Pacific Ocean. It’s the deepest place on Earth, even deeper than Mount Everest is tall!
To explore these deep places, special submarines are needed because the water pressure is so strong it could crush a regular submarine. Not many people have been to the deepest parts of the ocean, but those who have discovered incredible creatures.
Some of these creatures look like they belong in outer space! There’s the Anglerfish with its glowing lure, the colorful comb jelly, and the funny-looking blobfish. These discoveries show that the ocean is full of surprises, just like exploring a new planet.
The ocean is a mysterious place with so much to discover. Maybe one day, you’ll be the one to find something new and exciting in its depths. Remember, there are mysteries all around us, so stay curious and keep exploring!
Thanks for joining this adventure into the ocean’s depths. Until next time, keep asking questions and discovering the wonders of our world!
Try this simple experiment to understand how sonar works. Fill a large bowl with water and drop a small object, like a pebble, into it. Watch the ripples it creates. Now, gently tap the side of the bowl with a spoon and observe the ripples again. Discuss how the ripples are like sound waves used in sonar to measure ocean depth. Can you think of other ways sound helps us learn about things we can’t see?
Using a long piece of paper or a roll of craft paper, draw a vertical line to represent the ocean’s depth. Mark different depths, such as the average depth of the ocean, the deepest part of the Mariana Trench, and the height of Mount Everest for comparison. Use colors and drawings to add sea creatures and submarines at different depths. This will help you visualize how deep the ocean really is!
Think about what it would be like to live in the deep ocean. What kind of creature would you be? Draw a picture of your imaginary deep-sea creature and write a short story about its life. Consider how it finds food, what it looks like, and how it survives in the dark, high-pressure environment. Share your story with your classmates and see what amazing creatures they come up with!
Sure! Here’s a sanitized version of the transcript:
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(phone rings) – Hi, it’s Doug! So I’ve got my snorkel and my mask with me. If you ever get the chance to go snorkeling, you should try it. It’s so fun because there are all these interesting animals you can see, especially in a coral reef. With a snorkel, you have to stay near the surface of the water. You can’t go very deep because the snorkel is what lets you breathe.
Someone named Bao has a question about the ocean. Let’s give him a call now. (phone rings) – Hi Doug. – Hi Bao! – I have a question for you. How deep does the ocean go? – That’s a great question. For a long time, no one knew how deep the ocean went, or even what exactly was on the bottom of the ocean. In shallow waters, sailors would throw down an anchor to keep their boat from moving. But sometimes sailors would throw the anchor over the side and realize, oh, the anchor isn’t hitting the bottom. Whoa, the ocean must be really deep here. That made people wonder, how deep does the ocean go? How far down is the bottom?
If you were a sailor or a scientist, what would you do if you wanted to figure this out? Now would be a good time to pause the video and discuss. Okay, you ready? Well, you might think, if your rope wasn’t long enough, just get a longer rope. And that’s basically what sailors tried at first. They’d throw a long rope with a weight on the end. They’d feel when it hit the bottom, then they’d measure the rope to see how far down it was to the bottom.
But in some places, even then the weight might just keep going. Sometimes the weight wouldn’t hit the bottom until you used up three or maybe four miles of rope! And there were still other places where even that wasn’t enough rope. Places where it seemed like the ocean might be deeper than five miles. Of course, you could always get more rope to measure it, but eventually scientists figured out an easier way to measure the ocean’s depth. One that didn’t require any rope at all. It’s called sonar.
Instead of using rope, sonar uses sound to figure out how deep the ocean is. Yes, sound. It’s actually the same thing that bats use to find their way around. Bats make a sound and then listen for the echoes of the sound to bounce off the objects around them. Boats use sonar by sending sounds down toward the ocean bottom and then keeping track of how long it takes for the sounds to bounce back. Scientists can then use some simple math to calculate exactly how deep the ocean is in that spot. You see, the longer it takes the sounds to come back, the deeper the ocean bottom is.
Using this new sonar technique, scientists were able to create incredibly detailed maps of the ocean floor. And they found something surprising. It turns out there are huge underwater mountains rising up from the bottom of the ocean. Now because it’s so dark down there, we can’t easily get photographs. What you’re seeing here is an animation created using sonar. Some globes even have sonar maps of the ocean bottom.
This is the globe I had when I was young. I still have it. And you can see, look right there in the middle of the Atlantic Ocean. There’s actually an entire mountain range running all the way from the North Pole to the South Pole. It’s just underwater. When using sonar, scientists also discovered underwater canyons or trenches. These are found in certain parts of the ocean bottom. One of these trenches, the Mariana Trench, is in the Pacific Ocean, north of Australia. It was discovered to contain the deepest place on Earth. A spot so deep that you could fit all of Mount Everest inside of it. That’s nearly seven miles deep, over 36,000 feet.
The only way to get down there is using special submarines. The pressure of the water on top of you is so great, it would otherwise crush you. Not many people have ever been down there. In fact, more people have been to the moon than have been to the deepest place on Earth. But traveling to the bottom of the ocean is worth it. Every time a scientist or explorer visits the deep parts of the ocean, they find new creatures. Strange creatures.
Like the Anglerfish, a fish with giant teeth and a glowing lure dangling from the top of its head. Or creatures like the comb jelly, a relative of the jellyfish. Look at all those colors. Or maybe one of the weirdest creatures ever found in recent times, the blobfish, which has become famous on the internet. Many people say they would love to travel to outer space and maybe discover aliens one day. But the truth is, the bottom of the ocean might be just as interesting. Some of these creatures definitely look like aliens.
So in summary, the ocean goes very deep. The deepest spot on Earth is deeper than Mount Everest is tall. It’s hard to get to the deep parts of the ocean, but every time someone goes, we find amazing new things. Maybe you’ll be one of the people who discovers something new down there someday. That’s all for this week’s question. Thank you, Bao, for asking it.
Now for the next episode, I reached into my question jar and found three questions submitted to me that I’m thinking about answering. When this video is done playing, you’ll get to vote on one. You can choose from: can a plant grow without a seed? Why do birds lay eggs in spring? Or, how did cotton candy get its name? So submit your vote when the video is over. I want to hear from all of you watching. There are mysteries all around us. Stay curious, and see you next week.
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