Follow the latest news on the missing Titanic sub here
The grim discovery that a submersible imploded on its way to the wreck of the Titanic brought an end to the search for survivors that had gripped the world since Monday.
But many questions remain unanswered in the aftermath of the effort to find the Titan vessel.
The remote North Atlantic seabed may not be left in peace for some time as investigators try to work out what happened.
Here is what might happen next.
Search vehicles
The US Coast Guard said it would start demobilising craft and personnel who had assembled for the search and could have been involved in a deep-sea rescue.
But robot vehicles will continue to explore the debris site about 500 metres from the bow of the Titanic, Rear Admiral John Mauger from the coast guard said. He said no date was set for their withdrawal.
Investigation
Although investigators said the craft used by OceanGate Expeditions had broken apart underwater, the details of how, why, when and where remain unclear.
OceanGate co-founder Guillermo Sohnlein told Times Radio that learning lessons from an investigation was “the best way to preserve the memories and the legacies of those five explorers”.
Admiral Mauger said coast guards would try to help bereaved families find closure by establishing what happened.
It was not clear who would take part in the investigation as the wreck is in a remote part of the North Atlantic and the Titan’s crew came from several different countries.
The US and Canadian militaries were involved in the initial search and coast guards corresponded with British and French consulates who had nationals on board the Titan.
Debris and retrieval
Investigators who found the Titan debris will “do the best we can to fully map out what’s down there”, undersea expert Paul Hankin said at a coast guard press conference.
But asked about retrieving the crew’s remains, the rear admiral made no promises and spoke of an “incredibly unforgiving environment”.
“The debris is consistent with a catastrophic implosion of the vessel,” he said.
OceanGate
The company’s founder and chief executive, Stockton Rush, was one of the five people on board the Titan.
OceanGate said in a tribute that Mr Rush and his fellow crew were “true explorers who shared a distinct spirit of adventure and a deep passion for exploring and protecting the world’s oceans”.
Mr Rush founded the company in 2009 and it had run expeditions to the Titanic in 2021 and 2022.
Accounts have emerged of Mr Rush embracing the risk of exploration despite concerns being raised about safety.
Whether the company could face any legal action over the tragedy was unclear. Former passengers on the $250,000 ride recalled signing waivers in which they accepted they would be “subject to extreme pressure”.
There were also questions of insurance for the Titan and for the Canadian icebreaker that towed it near the wreck site.
New rules
The Titan’s disappearance has shone a spotlight on the murky regulations surrounding deep-sea missions.
The wreck of the Titanic, which went down in 1912 after hitting an iceberg on its maiden voyage, lies in international waters far from any nation’s coast.
It lies about 1,450km off Cape Cod in Massachusetts, where the sea can be almost 4km deep.
Mr Sohnlein said regulations “are pretty sparse and many of them are antiquated and designed for specific instances”. However, he defended what he said was a “rigorous test programme” for the vessel.
Admiral Mauger said he expected undersea regulations would be “a focus of future review”.
Filmmaker James Cameron, who directed 1997’s Titanic and has been on deep-sea expeditions, told Reuters that “you shouldn’t be using an experimental vehicle for paying passengers that aren’t themselves deep ocean engineers”.
Future missions
The fate of the Titan, and newspaper headlines that the Titanic had “claimed five more lives”, were a stark reminder of the dangers of undersea exploration.
The Titanic International Society said it was “time to consider seriously” whether crewed missions to the wreck should end.
It said there was “relatively little remaining to be learnt” about the Titanic and that surveys could be done by robotic vehicles.
