From dive to tragic discovery: A timeline of Titan's ill-fated expedition to famous shipwreck

The wrecks of the Titanic and the Titan sit on the ocean floor, separated by 1,600ft (490m) and 111 years of history.

How they came together unfolded over an intense week that raised temporary hopes and left lingering questions.

The buildup: From Friday, June 16

The Polar Prince, a Canadian icebreaker ship, steamed out of Newfoundland on Friday, June 16, towing the experimental Titan submersible and carrying the five-man team headed to explore the iconic ocean liner's watery gravesite. Three missions involving other teams had been scrapped due to bad weather in the previous four weeks, but the latest OceanGate Expeditions group was hopeful.

“A weather window has just opened up and we are going to attempt a dive tomorrow,” renowned adventurer Hamish Harding said Saturday on Instagram. “More expedition updates to follow IF the weather holds!”

The dive down: Sunday, June 18 (8am, EDT)

Moving about the Polar Prince, mission participants were required to wear water-activated life vests, bright orange jackets, helmets and steel-toed boots, said Arnie Weissmann, a journalist who spent eight days aboard the support ship in May before his mission was aborted. Just before a dive, they’d change into fleece vests, black flight suits bearing the OceanGate logo and warm socks — no shoes allowed on the submersible.

The team was carried to the Titan’s launch and recovery platform by one of two inflatable dinghies named Stewie and Max. Once inside, they would sit on a platform, with their legs crossed or out straight.

“You could not be in that thing if you’re claustrophobic,” Weissmann said. “It’s literally like being in a tin can because it’s got rounded sides.”

The Titan submerged at 8am EDT on Sunday, according to the U.S. Coast Guard.

“Once the submersible is launched you will begin to see alien-like lifeforms whizz by the viewport as you sink deeper and deeper into the ocean,” the company wrote on its website when it advertised the expedition. “The descent takes approximately two hours but it feels like the blink of an eye.”

Contact lost: 10.45am

On Sunday, the vessel lost contact with the Polar Prince around 10.45am

The search: Sunday, June 18 (from 5.40pm)

At 5.40pm, nearly three hours after the Titan was expected to resurface and nearly eight hours after the last communication, the Polar Prince notified the U.S. Coast Guard that the vessel was overdue, setting off an intense international search and rescue.

After the craft was reported missing, the US Navy analysed its acoustic data and found an anomaly that was “consistent with an implosion or explosion in the general vicinity of where the Titan submersible was operating when communications were lost,” a senior Navy official later told The Associated Press.

Though it wasn’t made public at the time, the Navy passed on that information on Sunday to the Coast Guard, which continued its search because the Navy did not consider the data to be definitive, according to the official, who spoke on condition of anonymity to discuss sensitive technology.

Search continues: June 19 to 21

By Monday afternoon, a C-130 Hercules aircraft from North Carolina and a Canadian P8 aircraft with underwater sonar equipment joined the search. Tuesday brought better weather and increased visibility, and by that morning, 10,000 square miles (25,900 square kilometers) had been searched.

A US Air National Guard crew arrived that day, as did a Bahamian research vessel, Deep Energy, which deployed camera-equipped, remote-operated robots.

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