The Ocean is the Last Frontier For thousands of years people have how deep it was This distance was sailed Earth's oceans But what lies about six feet 1 8 m and is still below the surface has long remained used today It is called a fathom a mystery Ancient Viking sailors The weights also brought up took the first steps to finding out in samples of the soft dirt from the the 700s They dropped weights off ocean bottom The Viking sailors a long line of ships into the ocean had no way to analyze these Then they pulled them back up and samples used the arm span of a sailor to see The Vikings were the first known people to explore below the ocean's surface OOOOOOOOCEO
MAPPING THE OCEAN FLOOR Thickness in inches 13 cm of the metal walls of the Trieste needed to withstand the pressure of the Challenger Deep Earth's oceans are wide deep and hard to map There are maps of the ocean floor but not in great detail Only objects in the ocean larger than 3 1 miles 5 km are completely mapped There are planets that have more detailed maps Mars has been mapped to within 328 feet 100 m The Vikings were the first to try to measure the ocean depth They brought up samples of soft dirt from the ocean floor The HMS Challenger made an important ocean exploration voyage the 1870s In 1960 humans visited Challenger Deep the deepest point on Earth But it was an early clue into what is beneath the waves Those depths remained a mystery for many years In the 1870s a ship called the HMS Challenger made the first significant bottom of the ocean The Trieste took two people to challenger Deep exploration of the seafloor The ship traveled nearly 70 000 miles 113 000 km around the world Its crew mapped underwater features using a similar method to the Vikings They also discovered new species of life that they brought on in the Mariana Trench 35 810 feet 10 915 m below the surface of the Pacific Ocean board The ocean covers most of Earth But there is still a lot we do not know It was not until the 1930s that about it As technology advances humans got to actually see the scientists are finding out more about ocean floor New submarines were oceans every day able to dive thousands of feet In 1960 humans visited the very
The Ocean is Full of Extremes The ocean takes up a large portion ocean goes way deeper than that of Earth's surface Yet it has barely The deepest parts of the ocean are been explored One reason for this is in the Mariana Trench in the Pacific simply its size Ocean water covers Ocean Its deepest point Challenger more than 129 million square miles Deep is lower than Mount Everest 334 million sq km of Earth The is tall ocean is an extreme environment It is a tough place to explore At this depth there is intense pressure Without special equipment humans are not able to At 650 feet 200 m below the water s surface it gets very dark At 13 000 feet 3 960 m deep the water temperature is freezing There is no sunlight at this depth But the dive deeper than 165 feet 50 m Only three people have ever been to Challenger Deep It is difficult for scientists to explore the oceans because they are so vast 6
71 A NATIONAL MONUMENT Percent of Earth covered by ocean making up 97 percent of all water on the planet The Mariana Trench is near the island of Guam in the Pacific Ocean Because Guam is a territory of the United States the United States oversees the Earth's surface is mostly covered by ocean The ocean is very hard to explore for several reasons Mariana Trench The Mariana Trench Marine National Monument Ocean water becomes was established in 2009 This allows the National Wildlife Refuge System to help protect this unique part of Earth too dark to see as you get deeper High pressures mean only special equipment can survive certain depths For these reasons it may not be a surprise that explorers have seen only five percent of the ocean Earth's highest mountain Mount Everest is more than 29 000 feet 8 800 m above sea level
