Burning Questions | Oceans
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The disappearance of the submersible Titan during a visit to the wreck of the Titanic has raised questions about just what risks are involved in such an expedition to the deep.
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At some point in Autumn 1911, an enormous chunk of ice cleaved away from a glacier on the southwest of Greenland's vast ice sheet. Over the following months, it slowly drifted south, melting gradually as it was carried by the ocean currents and the wind.
Then, on the cold, moonless night on 14 April 1912, a 125m-long (410ft) iceberg – all that remained of the estimated 500m (1,640ft) chunk of ice that left a fjord in Greenlandthe previous year– collided with the passenger ship RMS Titanic as it made its maiden voyage from Southampton in the UK to New York, USA. In under three hours the ship had sunk, taking more than 1,500 passengers and crew to their deaths. The wreck now lies nearly 3.8km (12,500ft) beneath the waves at a site nearly 400 miles (640km) southeast of the Newfoundland coast.
Icebergs still pose a hazard to shipping – in 2019 1,515 icebergs drifted far enough south to enter transatlantic shipping lanesduring the months of March to August. But the Titanic's final resting place carries dangers of its own, meaning visits to the world's most famous shipwreck present a significant challenge.
With the disappearance of a five-person submersible while carrying paying passengers on a trip to the Titanic wreck, the BBC looks at what this region of the ocean floor is like.
Navigating in the deep
The deep ocean is dark. Sunlight is very quickly absorbed by water and is unable to penetrate much deeper than about 1,000m (3,300ft) from the surface. Beyond this point, the ocean is in perpetual darkness. The Titanic lies within a region known as the "midnight zone" for this very reason.
Previous expeditions to the wreck site have described descending for more than two hours through total darkness before the ocean floor suddenly appears beneath the lights of the submersible.
With limited line of sight beyond the few metres illuminated by the truck-sized submersible's onboard lights, navigating at this depth is a challenging task, making it easy to become disoriented on the seabed.
What is it like visiting the Titanic on a sub?
Watch MikeReiss describe his own journey to the Titanic on an earlier expedition in the video above
Detailed maps of the Titanic wreck site put together by decades of high-resolution scanning, however, can provide waypoints as objects come into view. Sonar also allows the crew to detect features and objects beyond the small pool of light illuminated by the submersible.
Submersible pilots also rely upon a technique known as inertial navigation, using a system of accelerometers and gyroscopes to track their position and orientation in relation to a known starting point and velocity. OceanGate's Titan submersible carries a state-of-the-art self-contained inertial navigation system which it combines with an acoustic sensor known as a Doppler Velocity Log to estimate the depth and speed of the vehicle relative to the sea floor.
Even so, passengers onboard previous trips to the Titanic with OceanGate have described just how hard it is to find their way upon reaching the ocean floor. Mike Reiss, a TV comedy writer who worked on The Simpsons and took part in a trip with OceanGate to the Titanic last year, told the BBC: "When you touch bottom, you don't really know where you are. We had to flail around blindly at the bottom of the ocean knowing the Titanic is somewhere there, but it is so pitch dark that the biggest thing under the ocean was just 500 yards (1,500ft) away and we spent 90 minutes looking for it."
Crushing depths
The deeper an object travels in the ocean, the greater the pressure of the water around it grows. On the seabed 3,800m (12,500ft) underwater, the Titanic and everything around endures pressures of around 40MPa, which are 390 times greater than those on the surface.
"To put that into perspective, that is about 200 times the pressure of what is in a car tyre," Robert Blasiak, an ocean researcher at the Stockholm Resilience Centre at Stockholm University, told the BBC Radio 4's Today programme. "That is why you need a submersible that has really thick walls."
The carbon-fibre-and-titanium walls of the Titan submersible are designed to give it a maximum operating depth of 4,000m (13,123ft).
Titanic sub: Why it's so hard to find
Bottom currents
The strong surface currents that can carry boats and swimmers off course are probably more familiar to us, but the deep ocean is scoured by underwater currents too. Although usually not as strong as those found on the surface, these can still involve the movement of large amounts of water. They can be driven by winds at the surface affecting the water column below, deep water tides or differences in the water density caused by temperature and salinity, known as thermohaline currents. Rare events known as benthic storms – which are usually related to eddies on the surface – can also cause powerful, sporadic currents that can sweep away material on the seabed.
What information there is about the underwater currents around the Titanic, which is split into two main sections after the bow and stern broke apart as it sank, come from research studying patterns in the seabed and the movement of squid around the wreck.
Part of the Titanic wreck is known tolie close to a section of seabed affected by a stream of cold, southward-flowing water known as the Western Boundary Undercurrent. The flow of this "bottom current" creates migrating dunes, ripples and ribbon-shaped patterns in the sediment and mud along the ocean floor that have given scientists insights into its strength. Most of the formations they have observed on the seabed are associated with relatively weak to moderate currents.
Sand ripples along the eastern edge of the Titanic debris field – the splatter of belongings, fittings, fixtures, coal and parts of the ship itself that spread out as the ship sank – indicate there is an easterly to westerly bottom-flowing current, while within the main wreckage site, scientists say the currents trend from northwest to southwest, perhaps due to the larger pieces of the wreck, altering their direction.
Around to the south of the bow section, the currents seem particularly changeable, ranging from northeast to northwest to southwest.
Crews are protected from the crushing pressure of the deep ocean by the thick, reinforced walls of their submersible (Credit: Alamy)
Many experts expect the winnowing of these currents to eventually bury the Titanic wreckage in sediment.
Gerhard Seiffert, a deep-water marine archaeologist who recently led an expedition to scan the wreckage of the Titanic in high resolution, told the BBC that he did not believe the currents in the area were strong enough to pose a risk to a submersible – provided it had power.
"I'm not aware of currents representing a threat for any functioning deep-sea vehicle at the Titanic site," he says. "The currents… in the context of our mapping project, represented a challenge for precision mapping, not a risk for safety."
The wreck itself
After more than 100 years on the seabed, the Titanic has gradually degraded. The initial impact of the two main sections of the vessel when it collided with the seafloor, twisted and distorted large sections of the wreckage. Over time, microbes feeding off the iron of the ship have formed icicle-shaped "rusticles" and are speeding up the deterioration of the wreck. In fact, scientists estimate that the higher bacterial activity on the stern of the ship – largely due to the greater level of damage it endured – is causing it to deteriorate 40 years faster than the bow section.
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"The wreck is constantly collapsing, mainly due to corrosion," says Seiffert. "Each year a tiny bit. But as long as you keep a safe distance – no direct contact, no penetration through openings – no harm is to be expected."
Sediment flows
Although it is extremely unlikely, sudden flows of sediment along the sea bed have been known to damage and even carry off human-made objects on the ocean floor in the past.
The biggest of these events – such as the one that severed transatlantic cables off the coast of Newfoundland in 1929 – are triggered by seismic events such as earthquakes. There is a growing appreciation of the risk these events pose, although there isn't any indication that an event like this is involved in the disappearance of the Titan submarine.
The Titanic is slowly collapsing as the pressure of the ocean, sediment movements and iron-eating bacteria nibble away at its structure (Credit: Alamy)
Over the years, researchers have identified signs that the seabed around the Titanic wreck has been hit by huge underwater landslides in the distant past. Huge volumes of sediment appear to have cascaded down the continental slope from Newfoundland to create what scientists call an "instability corridor". They estimate the last one of these "destructive" events occurred tens of thousands of years ago, creating layers of sediment up to 100m (328ft) thick. But they also happen extremely rarely, says David Piper, a marine geology research scientist with the Geological Survey of Canada, who has spent many years studying the seabed around the Titanic. He compares such events to the eruption of Mount Vesuvius or Mount Fuji in terms of how often they might occur – on the order of once every tens of thousands to hundreds of thousands of years.
Other events known as turbidity currents – which are where water becomes loaded with sediment and flow down the continental slope – are more common and may be triggered by storms. "We show a repeat interval of perhaps 500 years," says Piper. But the topography of the seafloor in the area would likely steer any flows of sediment down a feature known as "Titanic Valley", meaning it would not reach the wreck at all.
Both Seiffert and Piper say it is unlikely that such an event might have played a role in the disappearance of the Titan submersible.
There are other geological features around the wreck site that have also still to be explored. In a previous expedition to Titanic with OceanGate,Paul-Henry Nargeolet – a former French Navy diver and submersible pilot – visited a mysterious blip he picked up on sonar in 1996. It turned out to be a rocky reef, covered in sealife. He had hoped to visit another blip he had detected near the Titanic wreck in the latest expeditions.
While the search for the missing craft continues, there are few clues about what may have happened to the Titan and its crew. But in such a challenging and inhospitable environment, the risks of visiting the wreck of the Titanic are as relevant today as they were in 1986 when the first people to set eyes on the vessel since it sank made the journey to the depths.
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FAQs
Why did the Titanic sink answers? ›
On the night of April 14, 1912, just four days after leaving Southampton, England on its maiden voyage to New York, the Titanic struck an iceberg off the coast of Newfoundland and sank.
Why didn't the watertight compartments work on the Titanic? ›The rapid sinking of the Titanic was worsened by the poor design of the transverse bulkheads of the watertight compartments. As water flooded the damaged compartments of the hull, the ship began to pitch forward, and water in the damaged compartments was able to spill over into adjacent compartments.
Why can't they pull the Titanic out of the ocean? ›There are fears that during retrieval, the Titanic wreck would disintegrate into pieces, making it impossible to have something concrete by the time the remains reach the sea surface. There are documented reports that metal-eating bacteria has already consumed most of Titanic's wreckage.
What happened to all the bodies in the water after Titanic? ›Of the 337 bodies recovered, 119 were buried at sea. 209 were brought back to Halifax. 59 were claimed by relatives and shipped to their home communities. The remaining 150 victims are buried in three cemeteries: Fairview Lawn, Mount Olivet and Baron de Hirsch.
Would the Titanic have sunk if it didn t try to avoid the iceberg? ›Answer: That's wrong – it would probably have survived. When a ship hits an iceberg head on, all the force would be transferred back to the ship, so it wouldn't have ripped open, but crumpled round, so only 2-3 compartments would have been breached. It was built to survive with 4 compartments breached.
How long did Titanic passengers survive in water? ›How Cold Was The Water? -2°C – the temperature of the sea water (around 28°F). 15-45 minutes – the typical maximum life expectancy of the Titanic victims in the water.
Does the iceberg that sank the Titanic still exist? ›The average lifespan of an iceberg in the North Atlantic typically is two to three years from calving to melting. This means the iceberg that sank the Titanic "likely broke off from Greenland in 1910 or 1911, and was gone forever by the end of 1912 or sometime in 1913."
Why can't the Titanic be brought up? ›Now it turns out that the Titanic will stay where it is, at least for now, as it is too fragile to be raised from the ocean floor. The acidic salt water, hostile environment and an iron-eating bacterium are consuming the hull of the ship.
Who owns Titanic wreck? ›The following year, however, a company called Titanic Ventures co-sponsored a survey and salvage operation of the wreck, and was eventually granted title to artifacts retrieved there, iNews said. In May 1996, Titanic Ventures sold its interests to the salvage firm RMS Titanic Inc.
Did anyone survive the Titanic that was not in a lifeboat? ›It was her sister, Edna Kearney Murray who survived the sinking of the Titanic but it wasn't in an overloaded lifeboat. “My great aunt Edna was in England at the time and had purchased a ticket for return passage to America on the Titanic,” Chris said.
Are there still skeletons in the Titanic? ›
Are there skeletons on the Titanic? No intact human bodies or skeletons remain in the Titanic wreckage. The wreck was first located and explored in 1985 and no bodies were visible then, or on any of the other times that it has been visited.
Were any skeletons found on the Titanic? ›Some 1,160 people went down with the Titanic. but no bodies have ever been found. There are multiple theories as to why, although experts have been unable to completely solve the mystery once and for all.
Was the captain of the Titanic found? ›While we cannot know for sure how he spent his final moments, it is known that Captain Edward Smith perished in the North Atlantic along with 1517 others on April 15, 1912. His body was never recovered.
What was the real reason the Titanic was found? ›The 1985 discovery of the Titanic stemmed from a secret United States Navy investigation of two wrecked nuclear submarines, according to the oceanographer who found the infamous ocean liner.
What did they find in the Titanic safe? ›A purser's safe brought up from the wreck last summer contained an assortment of gold-colored British coins, whose value was estimated by an expert at about $5,000.
Was the captain of the Titanic drunk? ›The liner Titanic leaves Southampton, England on her maiden voyage to New York City in 1912. THE captain of the Titanic was drunk when the liner hit an iceberg and sank, a newly unearthed document alleges. Captain Edward Smith apparently was seen drinking in the saloon bar of the ship before the collision.
How many dogs survived the Titanic? ›Three small dogs, two Pomeranians and a Pekingese, survived the Titanic disaster cradled in their owners' arms as they climbed into lifeboats.
Would the Titanic have survived if it hit head-on? ›The Titanic would founder. (By reversing the engines, Murdoch actually caused the Titanic to turn slower than if it had been moving at its original speed. Most experts believe the ship would have survived if it had hit the iceberg head-on.)
Did any swimmers survive Titanic? ›Joughin survived the sinking, swimming to upturned collapsible lifeboat B and remaining by it until he was picked up by one of the other lifeboats.
How long did it take to freeze to death Titanic? ›A water temperature of a seemingly warm 79 degrees (F) can lead to death after prolonged exposure, a water temperature of 50 degrees can lead to death in around an hour, and a water temperature of 32 degrees – like the ocean water on the night the Titanic sank – can lead to death in as few as 15 minutes.
Are any of the survivors of the Titanic still alive? ›
There are no survivors of the Titanic alive today
The very longest-living person to have survived the Titanic died on the 31st of May 2009. Her name was Elizabeth Gladys 'Millvina' Dean, and she was just two months old when she boarded the Titanic with her family.
Based on its trajectory, the iceberg would have eventually melted away when it reached the warm waters of the Gulf Stream approximately two weeks after striking the Titanic. According to reports by survivors, the iceberg was about 50 to 100 feet tall and may have been as much as 400 feet long.
Whose fault was it that the Titanic sank? ›The Titanic sank from human error. According to the granddaughter of the second officer of the Titanic, Louise Patten, a new steering system led to a mistake by the steersman, Robert Hitchins, into going "hard a port" instead of "hard a starboard" and straight into the iceberg instead of away from it.
Has a ship hit an iceberg since the Titanic? ›However, the Titanic was neither the first one nor the last ship to ever hit the iceberg and sink. Herein are mentioned world's top ten ships sunk by accident with icebergs (in terms of lives lost).
Why did it take 73 years to find the Titanic? ›Efforts to locate and salvage the Titanic began almost immediately after it sank. But technical limitations—as well as the sheer vastness of the North Atlantic search area—made it extremely difficult.
Will Titanic ever be lifted? ›The Titanic sank in 1912, and ever since people have wanted to salvage it. There are many reasons why the ship cannot be raised. Over 1,500 people died when it sank; it's considered a gravesite. The ship is also deteriorating.
Will they try to raise the Titanic? ›Since its discovery, there has been no more talk of raising the Titanic, and it is now protected by a UNESCO convention. The decaying ocean liner will be left to slowly disintegrate at the bottom of the Atlantic. The best estimate is that the ship will last just 14 more years before its current form totally collapses.
Who bought a ticket on the Titanic but didn't go? ›As the Titanic was the height of luxury in 1912, some celebrities had tickets for its maiden voyage. But not all of them ended up boarding the ship. J. Pierpont Morgan and Milton Hershey were among those who missed the disaster.
Can you take items from the Titanic? ›More On: titanic
RMS Titanic, a subsidiary of Premier Exhibitions, became the ship's official “salvor-in-possession” in 1993, making it the only entity allowed to collect artifacts from the wreck.
Appraisers have valued the Titanic items at $200 million. The salvage rights to the ship are also being sold. Clearly, interest in the tragedy among members of the public, collectors, and museums remains strong. A cracker from the ship sold for $23,000 last year.
Was Rose from Titanic real? ›
No, Rose and Jack Dawson, played by Kate Winslet and Leonardo DiCaprio respectively, aren't based on real people in Titanic – however, certain facets of Winslet's character were inspired by the American artist Beatrice Wood.
How long did Titanic survivors wait for rescue? ›The RMS Titanic sank on April 15, 1912 — 111 years ago — after it hit an iceberg. The RMS Carpathia, which was three hours away, came to the rescue of the stranded survivors.
Who was the last person rescued from the Titanic? ›Eliza Gladys Dean (2 February 1912 – 31 May 2009), known as Millvina Dean, was a British civil servant, cartographer, and the last living survivor of the sinking of the RMS Titanic on 15 April 1912. At two months old, she was also the youngest passenger aboard.
Where did the Titanic bodies go? ›Where are the Titanic victims buried? Around two-thirds of the bodies recovered after the sinking were transported to Halifax in Nova Scotia, Canada for burial, whilst a third were buried at sea. 306 – the number of bodies that were recovered by the CS Mackay-Bennett (bodies 1 to 306).
Has anyone been inside the Titanic since it sank? ›The last manned dive to the Titanic was in 2005, and this latest expedition was led by Victor Vescovo, an American private equity investor and retired naval officer who is the founder of exploration company Caladan Oceanic, Titanic historian Parks Stephenson, Rob McCallum, founder of specialist tour operator EYOS ...
How many children died on the Titanic? ›How many children died on the titanic? Around 109 children were onboard when the titanic sank. And about half of the number, around 59 to 60 children, died. Only one child travelling in first class died.
How many survivors were pulled from the water after Titanic sank? ›At least 31 crewmen claimed to having been in the water. In all, from 44 to 48 were actually saved from the water while about 79 passengers and crew have have been found who said they had been in contact with the water.
How many bodies were not found after the Titanic? ›While seeking to enhance their custodial role, federal officials are now pressing the question of the missing dead. After the Titanic sank, searchers recovered 340 bodies. Thus, of the roughly 1,500 people killed in the disaster, about 1,160 bodies remain lost.
Were third class passengers locked below on the Titanic? ›The British Inquiry Report noted that the Titanic was in compliance with the American immigration law in force at the time - and that allegations that third class passengers were locked below decks were false.
What was wrong with the rivets on the Titanic? ›Microscopic analysis of iron rivets recovered from Titanic revealed high concentrations of slag residue in the head area (seen as yellow, orange and red) that may have made them brittle in cold temperatures.
Why didn't the Titanic stern stay afloat? ›
It is widely believed that Titanic's stern was still connected to the bow and mid-ship section after the ship split at least for a period of time... enough so to force massive amounts of seawater inside the still very dry stern section causing her to quickly sink within a minute or two after the break.
How many compartments could the Titanic survive? ›The tragic disaster influences Atlantic shipping lanes more than 100 years later. The Titanic had been called unsinkable for many reasons, but one was that it had 16 watertight compartments to help keep it afloat. According to ship engineers, the Titanic could afford to flood four of those compartments and still sail.
What was the biggest mistake on the Titanic? ›1. Icebergs – the ultimate hazard. The poor navigation of icebergs is undoubtedly the most well-known and momentous of mistakes that caused the sinking of the Titanic. Indeed, the collision between the Titanic and an iceberg – on 14 April 1912 at 11:40pm – is what caused the tragedy.
Why are there no skeletons on the Titanic? ›Some Titanic experts say a powerful storm the night of the wreck scattered the life-jacketed passengers in a 50-mile-wide area, so it's likely the bodies scattered across the seafloor. Other experts say hundreds of people were trapped inside the ship when it sank.
What mistake did the captain of the Titanic make? ›The Titanic sank from human error. According to the granddaughter of the second officer of the Titanic, Louise Patten, a new steering system led to a mistake by the steersman, Robert Hitchins, into going "hard a port" instead of "hard a starboard" and straight into the iceberg instead of away from it.
Did any Titanic survivors swim to shore? ›Joughin proceeded to tread water for about two hours before encountering a lifeboat, and eventually being rescued by the RMS Carpathia. He is believed to be the very last survivor to leave the ship, and he claimed that his head barely even got wet.
Is the iceberg from the Titanic still there? ›The average lifespan of an iceberg in the North Atlantic typically is two to three years from calving to melting. This means the iceberg that sank the Titanic "likely broke off from Greenland in 1910 or 1911, and was gone forever by the end of 1912 or sometime in 1913."
Would the Titanic survived if it hit head on? ›The Titanic would founder. (By reversing the engines, Murdoch actually caused the Titanic to turn slower than if it had been moving at its original speed. Most experts believe the ship would have survived if it had hit the iceberg head-on.)
Did any 2nd or 3rd class passengers survived Titanic? ›Around 285 second class passengers were on board. Around 118 second class passengers survived.
What was found eating the Titanic? ›One of these is a species of bacteria -- named Halomonas titanicae after the great ship -- that lives inside icicle-like growths of rust, called "rusticles." These bacteria eat iron in the ship's hull and they will eventually consume the entire ship, recycling the nutrients into the ocean ecosystem.