Five people are on board the OceanGate Expedition company submersible that disappeared on Sunday in the Atlantic Ocean, 700 kilometers off the coast of the island of Newfoundland, Canada, when it was submerged to see the remains of the Titanic, from 1912 and located at 3,800 meters deep. Among the missing are Pakistani businessman Shahzada Dawood and his son Suleman, as well as Hamish Harding, a 58-year-old British explorer and billionaire businessman.

French explorer Paul Henry Nargeolet, an expert on the Titanic, is also believed to be another of the expedition members, Harding reported on his Instagram. The fifth person is Stockton Rush, CEO of OceanGate, who would serve as pilot.

The Coast Guard said there was a pilot and four “mission specialists” on board. “Mission specialists” are people who pay a fee of $250,000 to participate in OceanGate expeditions. During the dive, which usually lasts about ten hours, they take turns operating the sonar equipment and performing other tasks in the submersible with a maximum capacity of five people.

British businessman Hamish Harding, who lives in Dubai in the United Arab Emirates, is an adventurer who holds three Guinness World Records, including one for the longest time spent traversing the deepest part of the ocean in a single dive. In March 2021, he and ocean explorer Victor Vescovo dove to the lowest depth of the Mariana Trench. In June 2022, he was one of the first “tourists” to travel to space aboard the New Shepard rocket of the Blue Origin company, owned by Amazon founder Jeff Bezos.

Harding had posted on social media that he was proud to head to the Titanic as a “mission specialist”, adding: “Due to the worst winter in Newfoundland in 40 years, this mission is likely to be the first and only crewed mission to the Titanic in 2023”. Once on site, Harding reported that the submersible’s crew would attempt the dive after improved weather.

Harding was also aboard the 2019 “One More Orbit” flight mission that set a record for the fastest circumnavigation of the earth by aircraft over both geographic poles.

His family have confirmed that father and son are on board. Shahzada (father) is Vice President of one of Pakistan’s largest conglomerates, Engro Corporation, with investments in fertilizer, vehicle manufacturing, energy and digital technologies. According to the website for SETI, a California-based research institute of which he is a trustee, he lives in the UK with his wife and their two children.

The 77-year-old French explorer is director of underwater research at a company that owns the rights to the Titanic wreck. Former commander of the French Navy, he is both a diver and a minesweeper. After retiring from the Navy, he led the first Titanic recovery expedition in 1987 and is a leading authority on the wreck. In a 2020 interview with France Bleu radio, he spoke about the dangers of deep diving, saying, “I’m not afraid of dying, I think it will happen one day.”

The founder and CEO of the vessel’s operating company, US-based OceanGate, is also on the submersible, according to media reports. “It’s an incredibly beautiful wreck,” Rush told Britain’s Skyt News of the Titanic earlier this year. “Rush became the world’s youngest jet transport pilot when he earned his DC-8 Type/Captain rating at the United Airlines Jet Training Institute in 1981 at the age of 19,” according to his biography in the Ocean Gate website.