Here's the latest on the missing Titan submersible and the race to rescue passengers
As of Tuesday morning, international rescue crews are still searching the North Atlantic for a submersible vessel that was carrying five people to view the wreckage from the Titanic.
Authorities estimate there's only enough oxygen in the vessel for those onboard to survive about two more days.
Here's what we know.
When and where did the vessel go missing?
Titan had been deployed by a Canadian expedition ship, the Polar Prince, about 435 miles (380 nautical miles) south of St. John's in Newfoundland, not far from the site of the iconic shipwreck.
Why was the sub diving?
The missing vessel is owned by OceanGate, a company based in Washington state that offers underwater voyages to explore the remains of the Titanic from the seafloor.
OceanGate is a major chronicler of the ship's decay and shared the first-ever-full-sized digital scan of the wreck site in May.
OceanGate is also a pioneer in the deep sea tourism economy. For $250,000 a person, the company takes adventurers on a deep sea tour lasting eight days and stretching hundreds of miles.
From St. John's in Newfoundland, Canada, explorers travel 380 miles offshore and 2.4 miles below the surface.
If successful, they can catch a glimpse of what's left of the 1912 iceberg-crash disaster, which took the lives of all but 700 of the ship's 2,200 passengers and crew. Today, the Titanic is slowly succumbing to a metal-eating bacteria, which may cause it to fully disintegrate in a matter of decades.
Mike Reiss, who joined OceanGate to glimpse the deteriorating wreck in 2022, said the trip is less tourism than it is true exploration — and the people who dare to try it are made well aware of the risks.
"You sign a massive waiver that lists one way after another that you could die on the trip," he told the BBC in an interview Tuesday. "They mention death three times on page one. So it's never far from your mind. As I was getting on to the sub, that was my thought: That this could be the end."
'You sign a massive waiver that you could die on the trip'— BBC Breakfast (@BBCBreakfast) June 20, 2023
As search teams race against time to find the small sub that went missing during a dive to the wreck of the Titanic, writer Mike Reiss told #BBCBreakfast about taking the same trip last yearhttps://t.co/FNeiSyZfLl pic.twitter.com/2STvm7YDbz
Who was on board?
The Titanic-touring vessel contained one pilot and four paid passengers called "mission specialists," according to the U.S. Coast Guard. "Mission specialists" take turns operating sonar equipment and performing the tasks necessary to complete a dive.
Among those paid passengers was British businessman Hamish Harding, according to a tweet from Action Aviation, a company where Harding works as chairman.
Harding holds three Guinness World Records, including the longest duration (4 hours, 15 minutes) at a full ocean depth (2.88 miles) by a crewed vessel. He has also trekked to the south pole, circumnavigated the Earth in less than 48 hours and visited space in Blue Origin's New Shepard rocket.
Shahzada Dawood and his son Suleman, two members of a prominent Pakistani family known for investing, were also on board the vessel, according to a statement shared with outlets such as the Associated Press.
The fourth member of the crew may be Paul Henry Nargeolet, a French expert on the Titanic, according to an Instagram post from Harding.
Titan's pilot has yet to be identified.
Why did the vessel go missing?
It's still unclear why the sub lost communication with its control crew on the expedition ship.
Ahead of its launch, OceanGate said it would rely on the satellite-based internet company Starlink for its communications, given the lack of GPS capability at such a low depth.
OceanGate says its vessels are "equipped with some basic emergency medical supplies and 96 hours of life support," according to a previous page on the company's website, accessed via the Wayback Machine.
And for good reason: This is not the first time an OceanGate submersible has gotten lost, according to David Pogue, a correspondent for CBS Sunday Morning.
Pogue, who traveled on an OceanGate expedition to see the Titanic last summer, recalled that the control room was unable to help the submersible locate the wrecked liner for roughly three hours due to technical difficulties.
"The difference this year is that it seems like they lost contact with the ship," Pogue told NPR. "They can't even reach the sub and that's really scary."
He added that factors like bad weather and mechanical issues can hinder OceanGate's ability to complete a dive. In fact, the submersible vessels rarely make it to the Titanic, despite the expensive price tag, according to Pogue.
What's the latest on the search efforts?
At a press conference on Monday, Rear Adm. John Mauger of the U.S. Coast Guard said the search and rescue effort involved national, military and private companies, coming from both the U.S. and Canada.
Teams are using aircraft to scan the ocean as well as sonar devices to detect possible underwater sounds coming from the submersible.
In a Tuesday morning interview, Mauger said that crews have covered an area roughly the size of Connecticut. He indicated that crews were not able to detect any acoustics from Titan.
Overnight, the teams added an underwater search vessel with remotely operated vehicles in order to reach lower depths.
Crushing pressures, icy waters, a lack of light and the treacherous nature of the wreckage site itself all pose unique challenges to rescue operations if the vessel is detected at a lower depth. David Marquet, a retired U.S. Navy submarine captain, told NPR's Morning Edition that the odds of survival are "about 1 percent."
Mauger said the Coast Guard alone doesn't have all the resources it needs to perform such a complex search operation, let alone a rescue one.
Crews have been "working around the clock to bring all capabilities that we have to bear to find this submersible," Mauger said.
NPR's Juliana Kim contributed reporting.
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