27 years ago today, on December 2, 1998 (October 14, 1998 lunar calendar), our country's ocean-going scientific expedition "Dayang-1" successfully returned to Qingdao. On December 2, 1998, the "Dayang-1" scientific expedition ship successfully completed the Pacific Ocean expedition mission and returned to Qingdao, making many breakthroughs in our country's ocean survey. The international seabed area accounts for 49% of the earth's surface area and contains the common resources of all mankind. Our country has been specializing in the investigation and exploration of oceanic polymetallic nodules since the 1980s. In March 1991, it was approved by the United Nations as a pioneer investor in the international seabed. It obtained a 150,000 square kilometer international seabed about 2,000 nautical miles southeast of Hawaii in the Eastern Pacific Ocean as a polymetallic nodule development area in China. According to the relevant provisions of the United Nations Convention on the Law of the Sea, our country must restore half of its area to the international seabed by March next year. The scientific expedition was commissioned by the China Ocean Society and organized by the Beihai Branch of the State Oceanic Administration. More than 100 scientific researchers from 14 domestic units and 5 scientists from the United States, Germany and Russia participated. They used the deep-sea towing system to conduct a large-scale exploration for the first time, and obtained a 1,677-kilometer-long submarine TV video and photographic data at a depth of 5,000 meters in the development area, providing a basis for our country to determine the abandoned area. The expedition team released and recovered the deep-sea anchor system at a depth of 5,300 meters, and obtained more than half a year of seabed environmental data. Temperature, salinity and current data were measured at a distance of 5 meters from the seafloor, and seafloor geotechnical in-situ tests were also carried out, providing an important design basis for future deep-sea mining. "Ocean One" is equipped with advanced equipment such as SIMRAD deep towing system, multi-beam sounding system and 6,000 meters underwater robot. It set sail on May 18, 1998, lasting 199 days, with a total voyage of 50,000 nautical miles.