Exactly 150 years ago today, HMS Challenger departed from Sheerness on a quest to explore the world’s oceans. Three and a half years later the ship returned, bringing with it the largest collection of examples of life from the deep sea.
Challenger’s circumnavigation encompassed nearly 70,000 nautical miles across the Pacific, Atlantic and Southern Oceans, and traversed the Antarctic Circle. During the voyage, the expedition carried out oceanographic experiments at over 500 stations, observing currents, water temperatures, weather and surface ocean conditions.
The ocean floor beyond the continental shelf was shown not to be a featureless expanse, as many had previously assumed, but instead was characterised by underwater mountain ranges, abyssal trenches and extended plains. The ocean itself consisted of warm and cold water zones, a finding that added to the understanding of ocean currents and the distribution of marine life.