If you ask “What’s the highest point on Earth?” most people will correctly answer “Mt. Everest”. If you ask “What’s the lowest point on Earth?” you’ll get answers of “Death Valley” (the lowest land in North America at 86m below sea level), “The Dead Sea” (the lowest point in Asia at 423m below sea level), or maybe even “Marianas Trench” which is the lowest point on Earth. Located in the Pacific Ocean, it’s almost 11 km at its deepest, a place known as Challenger Deep. First explored in 1960 by humans, there wouldn’t be a return trip by man until 2012.
Just before Christmas in 1872, the HMS Challenger left Portsmouth, England on its four year mission of oceanography. It had nets for retrieving biological samples from different depths, housed six scientists, and travelled 127,000 km over four years. The mission discovered more than 4000 new species of plants and animals, but also discovered the Marianas Trench. Using a sounding line (a line with a weight on the end which is then lowered into the water) they were able to measure the deepest part of the trench. This point was then Challenger Deep after the HMS Challenger.
In 1953, a Swiss physicist named Auguste Piccard constructed and launched the Trieste, named after the Italian city in which it was built. With his son Jacques, the ship made its first dive on August 11. Over the next three years it would complete many more dives in the Mediterranean. These successes lead the United States government to investigate the craft in 1957, and it was recommended as the ideal craft to explore the Challenger Deep. It was bought for $250,000 in 1958 (worth approximately $1.6 million in 2012).
The dive to the Challenger Deep was uneventful. Manned by Lt. Don Walsh and Jacques Piccard, the submersible took nearly five hours to descend on January 23, 1960. During that time, the two occupants had little to do beside check gauges and look at the occasional bioluminescent sea life that swam by. At ~9.5 km they heard a bang which turned out to be the breaking of a secondary Plexiglass window in the entry tube, a non-fatal event. Once they reached the bottom they only stayed there for 20 minutes before returning up by dropping their ballast; the return trip only took 3 hours and fifteen minutes.
In March of 2012, James Cameron descended to the bottom of the Challenger Deep in a one-manned submersible. His descent took 2.5 hours and he spent 3 hours at the bottom, only half of his scheduled 6 hours which were cut short due to a hydraulic fluid leak. He brought multiple 3D cameras with him and recorded footage of his journey, and the team is eager to work out the kinks and try again. With only three people even reaching the bottom, Challenger Deep is one of the most remote places on the planet.
Today’s Tangent: As stated above, Mount Everest is the highest point in the world. But the highest point does not the tallest mountain make. Mount Everest is anywhere from 3.6 to 4.6 km high (3.6 on the south face and 4.6 on the north face) and is only the highest point because it’s in a mountainous region, raising its base more than 4 km. For the tallest mountain, look to Mauna Kea and Mauna Loa in Hawaii, both of which are 10.2 km tall though partly underwater. The tallest mountain on land is Mount McKinley in Alaska at 5.3 to 5.9 km tall.