wunder beta🌊 The Oceans
Dive into Earth's oceans, the vast blue waters that cover most of our planet.
What you’ll learn
- Describe the size of the ocean, name the five oceans, and identify the largest and deepest.Oceans cover about 71 percent of Earth. There are five connected oceans, and the Pacific is the largest and deepest. The Mariana Trench in the Pacific is the deepest known place on Earth.
- Explain why the ocean is salty, describe ocean life and motion, and how to protect it.The ocean is salty from minerals washed in over time. It teems with life like whales, fish, and coral reefs, and it constantly moves through waves, tides, and currents. Keeping the ocean clean protects sea life and us.
Questions this course answers
About how much of Earth's surface is covered by ocean?
Oceans cover about 71 percent of Earth's surface, which is why the planet looks blue from space.
How many oceans does Earth have?
Earth has five oceans: the Pacific, Atlantic, Indian, Southern, and Arctic, all connected as one body of water.
Which is the largest and deepest ocean?
The Pacific Ocean is the largest and deepest ocean, covering about a third of the whole planet.
Where is the deepest known place in the ocean?
The Mariana Trench in the western Pacific holds the Challenger Deep, the deepest known point in the ocean.
Why is ocean water salty?
Over millions of years, rivers and rain carried dissolved salt from rocks and soil into the ocean, making it salty.
What causes the ocean's tides to rise and fall?
Tides are caused mainly by the Moon's gravitational pull, which makes ocean water rise and fall along the shore.
Grounded in trusted sources
- Britannica, "Mariana Trench" — https://www.britannica.com/place/Mariana-Trench
- Smithsonian Ocean, "Mariana Trench" — https://ocean.si.edu/planet-ocean/seafloor/mariana-trench
- NOAA / National Ocean Service (facts on the five oceans and ocean coverage) — https://oceanservice.noaa.gov/facts/
- National Geographic Kids, "Ocean" habitat facts — https://kids.nationalgeographic.com/nature/habitats/article/ocean
Every Wunder lesson is built from real, reputable sources — never invented.
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