The great ocean mission eclipsed by Apollo 11
On July 15, 1969, one day before Apollo 11 launched for the moon, a crew of six men prepared to drop into unchartered and mysterious depths of the ocean.
Their ground-breaking mission, onboard a strange submersible craft called Ben Franklin, was to try and unlock secrets of the Gulf Stream, one of Mother Nature's most important ocean currents.
Flowing through the Atlantic Ocean, thousands of kilometres in length, the Gulf Stream affects much of the climate and life on earth.
The crew of six men, led by Swiss explorer and inventor Jacques Piccard, would lock the hatch on their vessel, drop to perilous depths of up to 500-metres and drift silently with the great ocean current for a period of 30 days.
Their intrepid adventure would forever be overshadowed by the lunar heroics of Neil Armstrong, Edwin 'Buzz' Aldrin, Michael Collins and Apollo 11, but it remains an incredible journey.
It took two years to build the Ben Franklin mesoscaphe, also known as the Grumman/Piccard PX-15, which was the manned underwater submersible where the men would live.
Built in Switzerland by Piccard and the Grumman Aircraft Engineering Corporation, the 130-tonne vessel was designed to float at depths of 150 – 550 metres, withstanding intense ocean pressures and allowing the study of the unpredictable forces of the Gulf Stream.
Originating in the Gulf of Mexico, the Gulf Stream stretches to the tip of Florida and follows the eastern coastlines of the United States and Newfoundland before crossing the Atlantic Ocean.
The US Navy and NASA were both involved in the project, providing technology and instruments to measure gravity and the earth's magnetic fields. Every item onboard the Ben Franklin had to be precisely weighted, otherwise the craft would not be able to float in the Gulf Stream at the perfect depth.
Joining the skipper, Piccard, and helping monitor the raft of then cutting-edge instruments and technology were Frank Busby, Kenneth Haigh, Don Kazimir and Erwin Aebersold.
Chester May, a NASA scientist, was also onboard, observing how the men coped while working cut off from the world inside a tightly confined and potentially life-endangering environment.
Around 10am on July 15 1969, the Ben Franklin was towed about 30 kilometres off the coast of Florida.
Piccard closed the hatch, and it would remain shut tight for 30 days.
One month later, on August 14, the submersible vessel resurfaced 2324 km from its starting point at Palm Beach, Florida. It bobbed in the ocean 480km south of south of Halifax, Nova Scotia in Canada.
During the voyage, the crew were dragged along in the swift current, measuring light levels, tracking sea life, monitoring audio in the ocean, current speed and underwater turbulence. At times, the craft was buffeted by huge underwater swells.
Above the Ben Franklin were several support ships, which Piccard could communicate with.
Later, documenting his adventure for The New York Times, Piccard described how deep under the ocean his crew had eagerly anticipated news of the Apollo 11 mission.
The message, when it arrived at 4:20pm on a Sunday afternoon, was short. Bereft of hyperbole, it simply read: "Two Americans have landed on the moon".
Piccard's crew recorded millions of measurements, which would later be scrutinised in detail by oceanographers and scientists.
Discovered by Benjamin Franklin in the 18th century, the Gulf Stream has a direct influence on weather and climate in the eastern seaboard of the US and Canada and western Europe.
Some scientists fear that melting glaciers could send cold water into the current and disrupt the Gulf Stream's flow.
That scenario could result in western Europe suffering far more extreme winters and sea levels quickly rise on the eastern seaboard of the US.
There is a possibility that without the warmth delivered by the Gulf Stream, Northern Europe could enter a new ice age.
The Ben Franklin made several more dives after its 1969 mission, including an expedition for Robert Ballard, discoverer of the wreck of the Titanic.
It ran aground on a reef in 1971, and was later sold to a Vancouver businessman.
After sitting idle on Hawaii's North Shore, the Ben Franklin was donated to the Vancouver Maritime Museum, where it is now on display.
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