Lost with the Titanic: Will submarine passengers' remains ever be found?

Corrections & clarifications: This story has been updated to clarify how many people died on the Titanic.

The shock of losing loved ones suddenly is one of the most troubling of tragedies. But add to that the mystery of where their bodies might lie at the bottom of the ocean.

For the families of the explorers who died in the Titan sub implosion, those are feelings likely to haunt them forever, as they have for generations of other families who lost relatives under similar circumstances: the sinking of the Titanic itself over a century ago.

No bodies have ever been found from the wreckage of the Titanic at a depth of 12,500 feet, where over 1,100 passengers are likely to have dissolved after years of salt-water erosion and undersea life foraging the site.

A similar scenario is likely for the Titan submersible. And then, there are the harsh realities of the violent implosion itself.

"It's not so much about deep sea as much as it is about the implosion. The force was compressing so rapidly that those bodies and souls had nowhere to go," said Aileen Maria Marty, an expert in infectious disease and disaster medicine at Florida International University's Herbert Wertheim College of Medicine.

Marty said that because of the way the sub imploded and likely crushed the bodies inside, "it’s very, very unlikely you’ll find any distinguishable body parts."

The conditions of the deep sea are so unknown and challenging and the implosion so catastrophic that the families of the five people who died could be long left with questions about what exactly happened to them.

On the ocean floor where the search crews found parts of The Titan 1,600 feet from the bow of the Titanic on Thursday, there is immense pressure, absolute darkness and extremely cold temperatures.

The Coast Guard said Thursday they did not know if they would be able to recover the five bodies.

The five passengers who were in the Titan submersible when it imploded on the mission were OceanGate’s CEO Stockton Rush, British billionaire explorer Hamish Harding, French maritime and Titanic expert Paul-Henry Nargeolet, one of the richest men in Pakistan Shahzada Dawood and his son Suleman Dawood.

They each paid $250,000 to take the voyage, which was promoted as an “extraordinary” expedition for travelers to become one of the few to “see the Titanic with your own eyes,” according to OceanGate’s archived itinerary of the mission. It was OceanGate’s third annual expedition to the Titanic, which struck an iceberg and sank in 1912, killing all but about 700 of the roughly 2,200 passengers and crew.

'True explorers' The 5 passengers who died on the missing Titanic submersible

US Coast Guard: Bodies lost in ‘catastrophic implosion’

The vessel was lost in a “catastrophic implosion,” the U.S. Coast Guard said Thursday.

“This is an incredibly unforgiving environment,” said Rear Admiral John Mauger of the U.S. Coast Guard.

It is likely that the bodies of the men were impacted with immediate trauma from the sudden pressure change in the implosion. And the extreme conditions of the deep ocean further complicates the search for them.

Marty said the implosion had to have happened at a tremendous speed.

"For something that size whole thing, the whole thing is going to crush in about 1 millisecond. So when it actually happened, their brains didn’t have time to know it was happening," said Marty.

In the case of the Titanic, more than 1,500 people were lost in the North Atlantic. Over 100 of the bodies were buried at sea due to their severe damage or decomposition, and crews at the time were only able to recover over 200 bodies.

Relatives of the Titanic passengers hoped for answers for decades. They never came.

The Titanic was the largest ship afloat at the time of its building in England, and was heralded as an "unsinkable" ship with little need for lifeboats. That hubris ended when the luxury liner sank in the North Atlantic Ocean on April 15, 1912 after striking an iceberg during her maiden voyage from Southampton, England, to New York City.

It took too long for a rescue ship to reach the sinking hulk and by the time it arrived, around 340 people were found floating dead in the freezing water, many wearing life jackets. But 1,160 bodies sank along with the ship and were never seen again.

Among them were some notable dignitaries of the time: U.S. businessman Benjamin Guggenheim, Titanic architect Thomas Andrews, and the ship's captain, Edward Smith. And many others.

James Delgado, a maritime archaeologist and historian who has dived to the wreck himself, told the DailyMail earlier this year that there could be "some semblance of human remains" still inside what's left of the Titanic.

"Scientists think that could be a possibility, but this is a science we don't know much about, particularly in the deep ocean," Delgado told MailOnline.

Bone degrades quickly in salt water. Delgado said that "even teeth dissolve" after sustained periods on the ocean floor, which is mostly populated by microbial life such as bacteria.

What are deep sea conditions like?

The deep ocean is one of the world’s most unforgiving environments with much of it still a mystery.

The deep sea “accounts for over 95 percent of Earth’s living space” and remains largely unexplored, according to the Smithsonian Ocean Portal. And only about 23% of the seafloor has been mapped, according to 2022 figures from the National Oceanic and Atmospheric Administration.

Human engineering and exploration of the deep ocean are limited by harsh conditions, such as increased water pressure, darkness and extremely cold temperatures — placing any deep sea mission at high risk.

“Light is virtually absent in the deep ocean,” according to the National Oceanic and Atmospheric Administration.

Habitats found in the deep sea are vastly different from other Earth environments and life below the surface have uniquely evolved to survive unforgiving conditions.

The Smithsonian Ocean Portal said by 13,000 feet, the average temperature “hovers just below the temperature of your refrigerator” and the weight of the water “continues to accumulate to a massive crushing force.” Most organisms with gas-filled spaces, or lungs, would be crushed by the pressure.

More: All five passengers on missing Titanic submersible dead after catastrophic implosion

How risky is deep sea tourism?

Extreme adventure tourism has made global headlines over recent years, marketing potentially dangerous adventures to paying customers.

The loss of the Titan this week shed light on a relatively new frontier for tourism: deep ocean exploration. The vessel was exploring the wreckage of the Titanic, about 900 miles off the coast of Cape Cod, Massachusetts, and about 12,500 feet underwater.

Operated by OceanGate, a private company based in Washington state, Rush sought to develop vessels that would break the boundaries of current submersibles and to discover the ocean’s unknown.

“One of the reasons I started the business was because I didn’t understand why we were spending 1,000 times as much money to explore space as we were to explore ... the oceans,” Rush told a conference held by GeekWire, a Seattle tech news website, last year. “There is no private access to the deep ocean, and yet there’s all this life to be discovered.”

Rush’s goals have been criticized by experts and explorers in light of the Titan's implosion.

Jon Council, a submersible expert and president of the Historical Diving Society, told NPR that while submersible tourism has been around for decades, OceanGate is the only company to have attempted to take customers down to depths as deep as the Titanic wreck.

And safety concerns were raised by former OceanGate employees. David Lochridge, OceanGate’s former director of marine operations, wrote in a 2018 lawsuit that it could subject passengers to “potential extreme danger.”

Marty also critiqued OceanGate for inviting passengers on the submersible given its safety concerns.

"There are perfectly good submersibles where it’s perfectly safe to go in them," she said. "But this was an experimental ship that was not certified and not ready to be taking tourists in."

Why did the men go on the voyage in the first place?

Each of the men came from different backgrounds and ultimately sought out exploration with the journey.

• Rush, 61, founded the OceanGate company that led the voyage to the wreckage of the Titanic. He was also the co-founder of OceanGate Foundation, a non-profit organization "which aims to catalyze emerging marine technology to further discoveries in marine science, history, and archaeology," according to the company's website. Rush said last year he turned to the deep ocean instead of space as his path to exploration.

• Harding was a British billionaire explorer and the chairman of Action Aviation, a global sales company in business aviation. He held three Guinness World Records related to his explorations by plane and into the deep ocean and he had also been to space. Prior to the journey, he wrote in a Facebook post: “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."

• Nargeolet was a French maritime and renowned Titanic expert, “having led six expeditions to the Titanic wreck site and lectured at numerous Titanic exhibitions around the world. He’s known as “Titanic’s Greatest Explorer,” according to OceanGate Expeditions. The trip was one of several dives he took to the Titanic.

• Pakistani businessman Shahzada Dawood and his son Suleman Dawood “shared a passion for adventure and exploration,” the Dawood family said in a statement. The older sister of Shahzada told NBC News that he was a lifelong Titanic obsessive and that Suleman agreed to go on the expedition because it was important to his father.

Contributing: The Associated Press

This article originally appeared on USA TODAY: Lost at sea: Titan victims killed in extreme adventure tourism