As the world anxiously waits for a missing submersible to emerge, a UK geophysicist says the mysterious banging noises that ignited hope of a safe return, may not be coming from the vessel.
Time is running out for the group on board, with roughly 12 hours of oxygen left as rescuers scramble to find the missing Titan submersible.
An extensive rescue mission was sparked after the submersible vessel on a tourist expedition lost contact an hour and 45 minutes into a 12,500 feet descent towards the Titanic wreck in the North Atlantic Ocean.
The vessel launched on Sunday morning (local time) carrying five men aboard, the founder and CEO of the vessel's US-based operating company OceanGate, a British billionaire, a Pakistani businessman and his 19-year-old son, and a French explorer.
Over the last couple of days, the US Coast Guard said banging sounds had been detected in the ocean sparking hope the missing group is still alive.
The underwater sounds were detected by sonar devices deployed to find the vessel, prompting a relocation of resources to explore its origin which still remains unknown.
Appearing on AM on Thursday morning, Reader in Forensic Geoscience Jamie Pringle said it is a very difficult search mission.
"The shared depth of water column, the obvious rugged nature of the ocean floor, and, of course, if it's in the debris field around the Titanic, it's going to be very difficult to find a very small sub versus with all the other debris," Dr Pringle said.
He said at this point rescuers know the mysterious noises are probably man-made but imagined the sound wouldn't be coming from the bottom of the ocean.
"It could be due to some search vessel noise for example, so that's not too positive," Dr Pringle said.
"The ocean isn't a big mass of water, it's leered, so normally sound will go more horizontally… I imagine it wouldn't be from the bottom of the ocean, it would be more of the top part."
He also noted sound waves travel to strength and with the vessel's mission to plunge to the bottom of the ocean, paired with the small size of the submarine, it is unlikely the sub could be heard from the depths of the water.
"The sound wave will travel proportionately to the strength of the source that it creates. So it would have to be a very strong noise from the bottom of this ocean upon that depth to get to near-surface depth," Dr Pringle said.
"We can't be too definitive and, of course, there's been other examples in the past where they've detected sound and it's turned out to be false alarms.
"So we can't be too hopeful but at least it's better than not hearing any sounds at all."
The Titan submersible is designed to take five people to depths of 4000 meters (13,123 feet) and has done several dives to the Titanic since 2021.
Because it travels so deep in the ocean, the submersible cannot use GPS and communicates through a text messaging system.
Operated by OceanGate Expeditions the tourist expeditions, which cost $250,000 per person, start in St. John's, Newfoundland, before heading out approximately 640km into the Atlantic to the wreckage site, according to OceanGate's website.
