Missing Titanic sub likely would have used its 96-hour oxygen supply if implosion didn't happen first

• According to estimates, the five people on the Titan submersible likely ran out of oxygen Thursday morning.
• It's impossible to say with certainty when their oxygen would run out.

The missing Titan submersible with five people on board likely would have out of oxygen Thursday morning, but a Thursday afternoon update from the US Coast Guard indicated that the vessel likely imploded before the search and rescue mission began Monday afternoon.

The Titan submersible appears to have had a "catastrophic loss of the pressure chamber," imploding in the ocean's depths and shattering its debris 1,600 feet away from the famous shipwreck its five passengers hoped to explore, the Coast Guard said, meaning the 96 hours of oxygen available to the passengers was likely not even a consideration in the rescue efforts.

OceanGate released a statement saying they believe the passengers onboard the Titanic expedition submersible have "sadly been lost," the statement read, per CNN.

The submersible went missing on Sunday during a dive to the Titanic shipwreck at the bottom of the Atlantic Ocean.

On Monday, the US Coast Guard estimated that there was 70 to 96 hours of breathable air on the sub when it took off.

The Titan initiated its dive at around 7 a.m. ET on Sunday, so 96 hours later would be around 7 a.m. ET on Thursday. Ninty-six hours was an estimate. As Insider's Amber Middleton reported earlier this week, the rate of consumption can vary significantly based on factors like how active the crew are and the temperature on board.

As of Thursday morning, rescuers had given no indication they knew where the submersible was.

By Thursday afternoon, the US Coast Guard announced that a "debris field" has been found in the depths of the North Atlantic by an underwater robot that was searching near the shipwreck.

"Experts within the unified command are evaluating the information," the agency said in a tweet.

A "catastrophic failure" could have killed everyone on board already, an expert told Insider. He said this could have come about from a power failure or the hull being breached, which would have brought about a "catastrophic implosion."

What happens to the human body in an enclosed vessel?

There is no research and little precedent for bodies being found in a highly pressurized and intact vessel, forensics experts told Insider.

The two big drivers of decomposition are temperature and oxygen, Melissa Connors, a director for the Forensic Investigation Research Station at Colorado Mesa University, told Insider. In general, the higher the temperature, the faster the body will decompose, and without oxygen, bacteria can't thrive, she said.

"Generally in an environment without oxygen, remains will not decompose much because the micro and macro organisms that would work to consume and decompose the tissues will be unable to survive," Nicholas Passalacqua, a director of Forensic Anthropology at Western Carolina University, said in an email to Insider.

In cold temperatures and without oxygen for bacteria, the body dries out through a process known as sublimation during which water goes from a solid state to a gaseous state, Connors said.

"So you might end up with mummies," she said.

There are other variables to consider, including anaerobes, a type of bacteria that does not require oxygen to survive and could contribute to decomposition, Daniel Wescott, director of the Forensic Anthropology Center at Texas State University, told Insider.