The Titanic tourist submersible has between 70 to 96 hours of oxygen left if it's still intact, the US Coast Guard says

• The tourist submersible that went missing has between 70 to 96 hours of oxygen left, per officials.
• That means the sub's oxygen will likely only last until Thursday afternoon E.T., at the latest.

The missing submersible that was bringing tourists to the Titanic shipwreck has between 70 to 96 hours of oxygen left, the US Coast Guard estimated on Monday afternoon.

"We understood that there was 96 hours of emergency capability from the operator," said Rear Adm. John Mauger at a press briefing in Boston. "And so we anticipate that there's somewhere between 70 to the full 96 hours available at this point."

Those estimates mean the oxygen in the submersible will likely last until Thursday afternoon on Eastern Time at the latest.

The vessel, called the Titan, is 22 feet long and typically contains four days of emergency oxygen for a crew of five, including the pilot.

The Titan went missing about an hour and 45 minutes into its dive on Sunday, per the Coast Guard, prompting a mass search and rescue operation in the Atlantic for the five people on board.

Mauger said rescuers are deploying a submarine, sonar buoys, and two search aircraft but added that the area is "remote" and challenging to search.

The search is being conducted around 900 miles east of Cape Cod at a depth of around 13,000 feet, he said.

Rescuers are also searching the surface of the ocean in case the Titan resurfaced but somehow lost communications with its main vessel.

The company that runs tours on the Titan, OceanGate Expeditions, provides underwater trips to see the sunken Titanic. A typical eight-day expedition comes with a price tag of $250,000 per person.

Because the Titan is a submersible — not a submarine — it lacks the power to leave port and return on its own, requiring a mother ship to launch and retrieve the vessel.