On 21 December 1872, HMS Challenger set sail from Portsmouth on a voyage that would transform our knowledge of our planet. Sailing with state-of-the-art equipment and a complement of 243 scientists and crew, the former British warship zigzagged for 70,000 nautical miles (130,000km) across the globe, taking thousands of physical, biological and chemical measurements of the sea and seabed.
Huge underwater mountain ranges, deep abyssal trenches and strange entities such as Venus’s flower basket – whose delicate tissue resembled spun glass – were discovered during the three-and-a-half-year expedition. Once thought to be a uniform watery expanse containing little of interest, the oceans were revealed to be deep, vibrant and filled with wonderful life forms.
