The US Coast Guard said on Thursday that the missing Titan submersible appears to have suffered a "catastrophic implosion" before search and rescue efforts even began.
And out of all the possible scenarios, an implosion was the quickest way the five passengers aboard could've died.
"It would happen quite quickly, and there would be little chance of surviving," Stefan Williams, a professor of marine robotics at the University of Sydney whose lab works with uncrewed submersibles, previously told Insider.
It's not clear exactly when the implosion happened, but the Coast Guard said search buoys deployed to help look for the missing sub didn't hear the sound of any collapse of the OceanGate vessel.
The Titan sub dove under the waves around 8 a.m. on Sunday and lost contact with a surface ship about an hour and 45 minutes later. The Coast Guard first heard from OceanGate that the sub hadn't returned at about 6 p.m. that evening.
The Coast Guard said two debris fields were found about 1,600 feet away from the bow of the Titanic wreck on the ocean floor indicating the submersible imploded in the "water column" nearby.
It's not clear if those aboard reached the Titanic before the implosion.
Science writer David Pogue — who previously reported on OceanGate and the Titan sub for CBS — said those aboard would have died immediately.
"Remember, as we know, at those pressures, if a molecule of water gets in, it's over instantly," Pogue told CNN's Jake Tapper on Thursday. "I know it's no great comfort to the families and the spouses, but they did die instantaneously. They were not even aware that anything was wrong."
