The hadal zone, also known as the hadopelagic zone, is the deepest region of the ocean. It lies within long narrow V-shaped depressions or “trenches” that range from around 6 to 11 km (3.7 to 6.8 miles) below sea level. In August, 2022, an international research group sent a deep sea exploration vessel with two crew members (one of whom was Japanese) to the 9801 meter deep seabed in the Izu-Ogasawara Trench in Japan. At that depth the water pressure is 1 ton per square centimeter. That is like holding a rhinoceros on the tip of your finger. They saw sea cucumber, sea anemone, shrimp, etc. at this depth. On the way there, they saw deepsea armored grenadier fish (シンカイヨロイダラ) and a species of eel, bassozetus robustus (ソコフクメンイタチウオ) at 6000 meter depth, and a snailfish (スネイルフィッシュ) and ghost snailfish (ゴーストスネイルフィッシュ) at 7000 meter depth. A snailfish has been successfully photographed at a depth of 8336 meters, and this was confirmed by the Guinness Book of World Records as “the deepest hadal zone fish ever found”.
