UPDATE: U.S. Coast Guard officials confirmed June 22 that large pieces of the Titan submersive vessel were discovered on the ocean floor near the Titanic wreckage, with evidence consistent with an implosion. OceanGate, which operated the mission, believes all five passengers on board have died. Read more on the tragedy here.
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For missing submersible passenger Stockton Rush, his ties to the RMS Titanic wreckage go beyond a professional interest—they're also personal.

After all, Wendy Rush, who is married to the OceanGate Expeditions' CEO, is the great-great-granddaughter of two of the Titanic's most famous victims, Ida and Isidor Straus. When the ocean liner began sinking after striking an iceberg in April 1912, Ida refused to leave her husband, who was the co-owner of Macy's department store, choosing to give up her seat on a lifeboat (where women and children had priority seating) in order to stay with Isidor on board.

As survivors of the disaster later recalled, Isidor and Ida stood arm in arm on the deck as the ship sank. 

The moving, tragic story of Isidor and Ida has made such an impact over the years that James Cameron incorporated it into Titanic. The 1997 film paid homage to the pair through an elderly couple who, rather than try to escape, choose to spend their final moments together in bed as the water comes rushing into their room. 

Wendy and Stockton married in 1986, per a New York Times wedding announcement.

But beyond his personal ties, Stockton has also expressed a professional and scientific urge to make viewing the Titanic wreckage a reality. 

When researchers found that the Titanic was slowly decaying due to metal-eating bacteria in 2019, Stockton says he felt a "pressing need to document the world's most famous shipwreck, combined with a huge demand of people who wanted to go see it," per NBC News. 

"It made perfect sense," he told the German broadcaster Deutsche Welle. "We just had to make the submersible to get there."

Titan, the 21-foot submersible owned by Stockton's company, and its five passengers disappeared on June 18 during a mission to explore the wreckage of the RMS Titanic, which is more than 350 miles off the coast of Newfoundland, Canada.

Over the last 24 hours, the international search even took on more urgency, as projections by the US Coast Guard estimated that the submersible's air supply was likely to run out by 7:10 a.m. ET on June 22. 

Keep reading to learn more about the passengers aboard the missing submersible.

On June 18, 2023, a deep-sea submersible Titan, operated by the U.S.-based company OceanGate Expeditions and carrying five people on a voyage to the wreck of the Titanic, was declared missing. Following a five-day search, the U.S. Coast Guard announced at a June 22 press conference that the vessel suffered a "catastrophic implosion" that killed all five passengers on board.

Pakistani-born businessman Shahzada Dawood and his 19-year-old son Suleman Dawood, both British citizens, were also among the victims.

Their family is one of the wealthiest in Pakistan, with Shahzada Dawood serving as the vice chairman of Engro Corporation, per The New York Times. His son was studying at the University of Strathclyde in Glasgow, Scotland.

Shahzada's sister Azmeh Dawood told NBC News that Suleman had expressed reluctance about going on the voyage, informing a relative that he "wasn't very up for it" and felt "terrified" about the trip to explore the wreckage of the Titanic, but ultimately went to please his father, a Titanic fan, for Father's Day.

The Dawood Foundation mourned their deaths in a statement to the website, saying, "It is with profound grief that we announce the passing of Shahzada and Suleman Dawood. Our beloved sons were aboard OceanGagte's Titan submersible that perished underwater. Please continue to keep the departed souls and our family in your prayers during this difficult period of mourning."

OceanGate CEO Stockton Rush was the pilot of the Titan. The entrepreneur—who founded the research company in 2009 in Everett, Wash.—had long been interested in exploration. Rush, 61, previously said he dreamed of becoming the first person on Mars and once said that he'd "like to be remembered as an innovator."

In addition to leading voyages to see the remnants of the Titanic, Rush had another surprising connection to the historic 1912 event: His wife Wendy Rush is the great-great-granddaughter of a couple who died on the Titanic, Ida and Isidor Straus.

British billionaire Hamish Harding confirmed he was a part of the mission in a June 17 Instagram post, a day before the submersible went into the water and disappeared.

"I am proud to finally announce that I joined @oceangateexped for their RMS TITANIC Mission as a mission specialist on the sub going down to the Titanic," he wrote. "Due to the worst winter in Newfoundland in 40 years, this mission is likely to be the first and only manned mission to the Titanic in 2023. A weather window has just opened up and we are going to attempt a dive tomorrow."

Harding—the chairman of aircraft company Action Aviation—said the group had started steaming from St. Johns, Newfoundland, Canada and was planning to start dive operations around 4 a.m. on June 18. The 58-year-old added, "Until then we have a lot of preparations and briefings to do."

His past explorations included traveling to the deepest part of the ocean in the Mariana Trench, telling Gulf News in 2021, "It was an incredibly hostile environment. To travel to parts of the Challenger Deep where no human had ever been before was truly remarkable."

The Dubai-based businessman also circumnavigated the Earth by plane with the One More Orbit project and, last year, took a trip to space on Amazon founder Jeff Bezos' Blue Origin New Shepard rocket. Harding shared his love for adventure with his son Giles, described as a "teen explorer" on his Instagram.

As for the fifth member, a representative for French explorer Paul-Henri Nargeolet told the New York Times that he was a passenger on the Titan, with Harding also referencing him on Instagram as a member of the team. 

The Times described him as a maritime expert who was previously part of the French Navy. The 71-year-old was a bonafide Titanic specialist and has traveled to the wreckage 35 times before. Nargeolet served as the director of RMS Titanic, Inc., a company that researches, salvages and displays artifacts from the famed ship, per the outlet. 

Alongside fellow passenger Hamish Harding, he was a member of The Explorers Club, founded in 1904.

As Harding noted in his post, the submersible—named Titan—was a part of an OceanGate Expeditions tour that explores the wreckage of the RMS Titanic, which infamously sank in 1912.

The company expressed its sympathies to the families of the victims. "These men were true explorers who shared a distinct spirit of adventure, and a deep passion for exploring and protecting the world's oceans," OceanGate said in a statement. "Our hearts are with these five souls and every member of their families during this tragic time. We grieve the loss of life and joy they brought to everyone they knew."

This story was updated June 22, 2023 at 6:45 p.m. PT with details of a U.S. Coast Guard press conference.

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