The Challenger expedition was one of the first scientific expeditions intended to gather data about the ocean's unexplored features. During the expedition which lasted from 1872-1876, the scientific crew gathered data on the temperature, water chemistry, currents, marine organisms and ocean floor deposits. The Challenger expedition, which undertook a series of geological, chemical and biological measurements, lay the ground for future oceanographic research. The scientific discoveries of the expedition were published in a 50 volume research report of 29,500 pages that took 23 years to compile.
In 1870, Dr. Charles Wyville Thompson suggested that the Royal Society of London obtained the permission from the Royal Navy to utilize one of its ships for scientific research purposes. The Royal Navy granted the permission and in 1872, the HMS Challenger was equipped with a number of laboratories, a specialized dredging platform, chemical equipment, thermometers, water sampling containers, sounding leads, equipment for the recollection of seafloor sediments and other specialized scientific equipment for surveying and exploring. Once loaded with oceanographic research equipment, the HMS Challenger sailed the oceans.
The saling route of HMS Challenger
The expedition left the port of Portsmouth, England on December 21st, 1872, travelling 70,000 nautical miles (130,000 km) during which the Challenger followed a path that led it south of the Atlantic and around the Cape of Good Hope in south Africa. From there, the Challenger sailed across the ocean waters of the southern Indian Ocean and the Antarctic Circle, then, it headed to Australia and new Zealand. From there, it traveled north to the Hawaiian Islands and then south through the west coast of the American continent until reaching Cape Horn at the southern tip of South America, where the ship sailed the Atlantic ocean and returned to Spithead, Hampshire, on May 24th, 1876.
During the more than one thousand days on the ocean waters, the HMS Challenger gathered scientific data at 362 oceanographic stations on temperature, water chemistry, ocean currents, marine biodiversity and the ocean floor. It also undertook 492 deep sea soundings, 151 open water trawls, 133 bottom dredges, 263 water temperature recordings and catalogued more than 4,500 new marine species. Among other scientific contributions are also included a map of ocean floor sediments, an outline of the shape of the ocean basins, the discovery of the mid-Atlantic Ridge and the Challenger Deep in the Mariana Trench.
The HMS Challenger's crew
The original crew which consisted of an approximate number of over 240 people, consisting of 21 naval officers, six members of the scientific staff and 216 crew members, was reduced to 144 by the time the expedition ended. This was due to a number of deaths on board the ship, illness and desertions. The scientific staff included Scottish naturalist Charles Wyville Thompson, who led the expedition, British naturalist John Murray, Henry Nottidge Moseley, Rudolf Von Willemoes-Suhm and John Young Buchanan.
Previously to the 19th century, most of the knowledge pertaining the oceans was that of the ocean surface, principally that regarding to shallow sea surface regions. Little was known about the ocean depths prior to the 19th century; however, a new perspective for further ocean exploration was opened after the new discoveries of the HMS Challenger arouse in other nations an increased interest in the exploration of the oceans. According to nap.edu, the HMS Challenger expedition is considered the first major oceanographic expedition, as it was the first attempt to perform a series of systematic measurements of the ocean.