Five missing tourists lost near the wreck of the Titanic may have experienced lung-crushing pressure, ‘nitrogen narcosis’ and hypothermia if the 22ft sub’s hull cracked, experts have said. 

Rescue teams are racing against the clock three days after the deep-sea vessel Titan disappeared.

While there have been some signs they still may be alive, what caused the submarine to go missing and its eventual fate, is still unknown.

One scenario is a hull breach while the vessel was in the deep ocean, and if this has to occurred experts say the occupants odds of survival are almost zero. 

Dr Nicolai Roterman, a deep-sea ecologist at the University of Portsmouth, said if such an accident did occur the pressure would have killed the sub occupants almost instantly. 

‘If there was any kind of hull breach, the occupants would succumb to the ocean in a near instant, given the more than 5,500 pounds per square inch pressure exerted by the ocean at the depth of 3,800m (12,467ft).’

Professor Alistair Greig, an expert in marine engineering at University College London added simply that if the hull had been compromised in anyway the ‘prognosis is not good’. 

Titan disappeared while diving towards the shipwreck of the Titanic, 12,500ft below the surface of the water.

The deepest human free dives, a deep swim without any equipment like scuba gear, only go to only 400ft and are still dangerous. 

Specialised equipment, like special gas mixtures to combat the intense pressure of the depths of the ocean, have only enabled human divers to reach depths of about 1,700ft. 

Even whales that have evolved to feed in the deep ocean only go to a maximum of 10,000ft.

The deep ocean is so inhospitable in part because of the pressure.

Standing on the Earth’s surface, your body is under constant but unnoticed pressure from the air that surrounds it.

Scientists call this one atmosphere, which translates to about 14.7lbs of pressure per square inch.

Once people go underwater they have to contend with the pressure of water, which is much denser than air, surrounding them.

This pressure increases the deeper you go due the weight of the water above, at the rate of one atmosphere per 33 feet. 

At the depth of the Titanic wreck, the pressure will be approximately 380 times what people experience on the surface. 

As the pressure from the water increases, it causes any space filled with air to collapse under the weight. 

For submarines with hull damage, this can then result in a breach, causing potential trauma to any occupants inside. 

And for biological systems, like lungs, the intense pressure can be catastrophic. 

Such pressure can be felt at a very basic level by swimming down in the deep end of a swimming pool as the water pressure begins to affect the internal air in your ears.

But at extreme depths this pressure becomes deadly.

An unprotected human exposed to the depths the Titan was aiming to reach would have their lungs collapse and their eardrums rupture from the weight of the water.

Fluid would then rush in through the mouth to fill the space left behind, and this would causing the unfortunate person to drown.

People can survive about 15minutes without oxygen, though they lose consciousness long before then, with brain damage is likely after just a few minutes without air.

If such a breach has happened on the Titan, the bodies of the occupants are unlikely to themselves be crushed.

The water pressure required to theoretically crush human bone is about 22miles, roughly three times deeper than the deepest recorded parts of the ocean.

However, such devastating injuries can occur in diving suits containing air, which then deform under the pressure, crushing their unfortunate occupants. 

But even with an air supply, another deep-sea hazard will hasten the end of anyone caught in such unfortunate circumstances.

At high pressures found in the deep sea, the body’s internal chemistry begins to change.

This results in nitrogen, which forms part of the air that we breathe, becoming more soluble, causing a dissolved form of the gas to enter the blood. 

As human tissue needs oxygen, not nitrogen, to survive, this imbalance causes a condition called nitrogen narcosis — with the body effectively suffocating from the inside out. 

Even without these factors, an unprotected person would also have to contend with the prospect of hypothermia setting in rapidly. 

The deep ocean receives little to no light, and temperatures at 12,500 feet are about 2°C (36°F).

In humans, hypothermia can set in water as cold as 4°C (40°F), with bodily systems beginning to shut down with people becoming tired and confusion.  

Various air breathing creatures, like whales, seals and sea turtles have evolved special adaptations to compensate for going so deep.

Some species pre-emptively collapse their lungs and slow down their bodily functions before plunging into the depths, surviving on the oxygen remaining in their blood.

Others have expandable and strong internal structures to help prevent the pressure from collapsing tissues. 

Titan lost communication with tour operators OceanGate Expeditions on Sunday while about 435 miles south of St John’s, Newfoundland during a voyage to the Titanic shipwreck off the coast of Canada. 

Titan has five people on board, including British billionaire adventurer Hamish Harding, as well as one of Pakistan‘s richest men, Shahzada Dawood, and his son Suleman.

The others on board are Shahzada Dawood, his son Suleman, 19, OceanGate’s chief executive and founder Stockton Rush and French submersible pilot Paul-Henry Nargeolet.  

If the hull was not breached and the vessel is instead stranded with no power its five passengers will be in total darkness in temperatures of around 3°C (37°F) as the craft rolls along the seabed. 

Yesterday, the US Coast Guard estimated the 22ft long vessel had just 40 hours of oxygen left.

This gives rescuers until tomorrow morning to find the vessel. 

Even if the vessel surfaced and is adrift in the ocean currents, it is designed to only be opened from the outside, meaning the time limit remains. 

OceanGate is also facing questions about why it took so long to alert authorities to the missing craft, only raising the alarm to the Coast Guard eight hours after losing contact. 

For all the chaos going on down here on Earth, it’s easy to forget that we live in a volatile galaxy full of formidable dangers. 

From space rocks flying at thousands of miles per hour, to black holes that could rip our planet apart, sometimes it’s best not to think about them. 

But what would actually happen to the human body if we perished at the hands of these wild astronomical phenomena? 

MailOnline spoke to experts to find out – and to see if there’s any chance of them actually occurring while humanity still exists. 

Before any of them happen, Homo sapiens could be responsible for their own demise – likely by creating dangerous AI or the emission of greenhouse gases.

WHAT IF THE SUN DIED OUT?

Scientists estimate that our sun is about 4.5 billion years old – about halfway through its anticipated 9 billion or 10 billion year-long lifespan. 

When it starts to die, the sun will expand into a red giant, becoming so large that it will engulf Mercury and Venus, and possibly Earth too. 

Of course, in another 4 or 5 billion years’ time humans will likely be long gone, likely wiped out by a climate disaster or an asteroid impact.

However, in the event that we’re still here when the sun dies, the effects would be felt immediately and we would suffer a speedy demise. 

‘Assume the sun decide to quit, we would follow very quickly,’ Albert Zijlstra, a professor of astrophysics at the University of Manchester, told MailOnline.

‘The bottom line answer is you’d freeze to death.’ 

According to Professor Zijlstra, the closest Earth has seen to such an event was the era of ‘snowball Earth’, some 700 million years ago.

‘The entire world was frozen and the sea was covered in a kilometer thick ice from pole to pole, lasting 50 million years,’ he said.

‘Not much survived life that – and that was with the sun almost as bright as it is now.’ 

Even if we somehow survived the cold for a few days, plants and crops would die due to the lack of sunlight for photosynthesis – and we would surely starve. 

Thankfully, the sun is ‘remarkably stable’ and in no danger of disappearing, Professor Zijlstra added – and is actually very slowly getting brighter. 

‘It is not perceptible on human timescales, but give it a billion years and it becomes very noticeable,’ he said. 

WHAT IF EARTH FELL INTO A BLACK HOLE?

Perhaps one of the scariest features of the universe are black holes – regions of spacetime where gravity pulls so much that even light can not get out.

Black holes act as intense sources of gravity that hoover up surrounding dust and gas, as well as planets and even other black holes. 

They are often described as ‘destructive monsters’ because they tear apart stars, consuming anything that comes too close, and hold light captive. 

With light unable to escape black holes, Earth would have little chance either. 

Xavier Calmet, a professor of physics at the University of Sussex, said the gravitational force of a black hole would become so strong that we would experience ‘spaghettification’.

‘Your body will be stretched into a shape similar to that of a long pasta until it is reaped apart by the strong gravitational force,’ Professor Calmet told MailOnline. 

‘I can’t imagine that this would be pleasant – it would happen rather quickly, so if painful, it is unlikely to last long.’ 

Dr David L Clements, a senior lecturer at Imperial College London’s physics department, said ‘the end would likely be quick’ if falling into a black hole.  

‘It could come from asphyxiation if the atmosphere is stripped, or from the process called spaghettification where tidal forces stretch everything out into long strings – maybe briefly painful.’ 

Thankfully, the chances of Earth ever being swallowed by a black hole are ‘nearly zero’, according to Dr Clements. 

‘The fact that we’re still here shows that this hasn’t happened over the whole history of the Earth,’ he told MailOnline.

‘So the chances are at least less than once every 4.5 billion years and likely much much less.’ 

The closest black hole to Earth, called Gaia BH1, is around 1,600 light years away and is 10 times the size as our sun, experts recently revealed. 

WHAT IF OUR SUN COLLIDED WITH ANOTHER? 

You may not be aware that our Milky Way galaxy is on a collision course with another galaxy called Andromeda, which is currently around 2.5 million light years away. 

The two galaxies have a strong gravitational attraction and will merge in approximately 4 billion years’ time to create one new super galaxy, referred to by astronomers as ‘Milkdromeda’. 

Eric Bell, professor of astronomy at the University of Michigan, said ‘very likely nothing’ will happen to us in the event of the galaxy collision.

As the merger occurs, it’s likely the sun will be flung into a new region of our galaxy, but Earth and the rest of the solar system won’t be in danger of being destroyed. 

However, one potential danger of a galaxy merger would be a collision (or near collision) between our star with another star, although there’s an extremely small chance that would happen. 

‘There is a considerable uncertainty in when [the galaxy merger] will happen, roughly several billion years from now,’ Professor Bell told MailOnline. 

‘But galaxy collisions would only be dangerous because of a slightly increased chance of star collisions.’ 

Even a near collision with another star – a ‘close pass’ – would affect our orbit, which Professor Bell said would be ‘very bad’. 

‘The close pass changes the orbit, bringing us closer to the sun, or bringing us further away. 

‘What our fate would be depends on exactly how our orbit changed. 

‘So we would either escape the solar system (in which case we’d slowly freeze to death over months), or get cooked by the sun (which may be very fast, or take months, depending on the orbit we ended up in).’ 

WHAT IF AN ASTEROID HIT EARTH? 

A massive asteroid hitting Earth was famously the cause of the extinction of the dinosaurs around 66 million years ago. 

The so-called Chicxulub rock, around six miles in diameter, slammed into a shallow sea in what is today the Yucatán peninsula in Mexico. 

For those not killed directly by the impact, the collision released a huge dust and soot cloud that triggered global climate change, wiping out 75 per cent of all animal and plant species. 

NASA scientists think it would take an asteroid 60 miles (96 km) wide to totally wipe out life on Earth – about 10 times bigger than Chicxulub. 

According to a 2022 research paper by Jean-Marc Salotti at the University of Bordeaux, a 60-mile asteroid would ‘kill all lifeforms’ if it hit Earth, with the possible exception of extremophiles, those tiny lifeforms that can survive high temperatures, acidity and radiation. 

Such an asteroid would ‘transform the Earth into an inhospitable planet’, causing the extinction of many life forms including the human species. 

But the bigger the asteroid that hits us, the quicker the end would likely be. 

If a small one hit Earth today, there would be a huge amount of dust thrown up into the atmosphere that could block out sunlight – freezing us to death, which would likely be more drawn out and unpleasant. 

If it hit water, then there would be an increase in water vapour in the atmosphere, which would result in an increase in rain resulting in landslides and mudslides.

Regionally there might be earthquakes, hurricanes and tsunamis due to the increase in kinetic energy. 

Dr Kelly Fast, program manager for NASA’s Near-Earth Object Observations initiative, said asteroids have hit Earth before and ‘it will happen again’. 

‘Finding them early is important for advanced warning and to mitigate against potential future impact threats,’ she said. 

WHAT IF EARTH’S ATMOSPHERE DISAPPEARED? 

Earth’s atmosphere is described as its ‘security blanket’ because it contains the oxygen we need to exist, making the air breathable. 

It also protects us from harmful ultraviolet solar radiation from the sun and creates the required pressure for liquid water to exist. 

If this precious multi-tiered atmosphere somehow disappeared, most vertebrates, including humans, would suffocate in seconds. 

Marine creatures, which rely on oxygen dissolved in the water, may last a little longer – although the seas would also boil into vapour due to the sun’s rays. 

In the event of the atmosphere disappearing, we may have to build radiation-shielded domes that provide a pressured environment and plentiful oxygen. 

But is there any chance of this actually happening? 

A 2021 study in Nature Geoscience concluded that Earth’s oxygen-rich atmosphere will be lost in about 1 billion years, but this will happen gradually as the sun gets hotter.

Carbon dioxide levels in the atmosphere will drop due to the gas absorbing the heat and breaking down, leading to death of plant life and in turn reduced oxygen production. 

All in all, it seems like the most realistic dangers to humanity are the ones of our own making – such as greenhouse gas emissions and killer robots. 

According to one academic, there’s a 50 per cent chance artificial intelligence will wipe out humanity, and it could happen in a similar way to how humans wiped out extinct animals such as the Dodo. 

Russia may be plotting to blow up Ukraine’s Zaporizhzhia Nuclear Power Plant, Kyiv has warned, after explosions at a major dam and hydroelectric plant caused mass flooding in the Kherson region and sparked a humanitarian disaster.

The Zaporizhzhia power plant is the largest nuclear power facility in Europe, and sits roughly 80 miles up the Dnieper river from the Kakhovka dam, which was heavily damaged in explosions on June 6. 

Since Russian troops invaded Ukraine in February 2022, fears of a nuclear disaster have been sparked on several occasions when the plant was shelled and was temporarily disconnected from Ukraine’s power grid some six times.

Those fears rose again when Ukrainian officials said the Zaporizhzhia power plant may be affected by the destruction of Kakhovka dam, whose water provides vital cooling for the nuclear reactors. 

Ukraine’s state nuclear company Energoatom later assuaged those fears when it declared that the Zaporizhzhia facility’s cooling pond was full and had enough reserves to manage. 

But Zelensky‘s top security official Oleksiy Danilov later said Putin’s next step may be to attack the Zaporizhzhia plant, which could result in catastrophic nuclear consequences.

With the help of Darya Dolzikova and Jack Watling of the RUSI think-tank, MailOnline examines whether Russia could – or would – risk destroying Europe’s largest nuclear power plant. 

Could Russia blow up the Zaporizhzhia nuclear power plant?

Yes. The power plant – Europe’s largest – sits on ground that is currently occupied by Russia and its troops are stationed at the plant. They are thought to have mined it, and have stored ammunition and explosives in and around the reactor buildings.

In April this year, a Russian mine exploded near the engine room of the fourth nuclear reactor, according to Ukraine’s nuclear power agency.

As Ukraine has built up towards its counter-offensive, more Russian units have been moved to the plant and defensive positions have been built on the roof. There are currently more troops at the plant than civilian staff.

Russian forces could therefore set off either a deliberate or accidental explosion at the site.

Would Russia blow up the plant?

Potentially. Russian officials responsible for the occupation of Ukraine do think in these terms, they have debated it, and it could offer some value to them.

The fact that it would cause suffering to Ukrainian civilians, Russian soldiers at the plant, and potentially fallout inside Russia itself should not be viewed as a deterrent.

Russian authorities have repeatedly warned about the risks of a dirty bomb attack in Ukraine or false-flag attacks on the plant, creating a pretext to blame Kyiv for any disaster.

There is no indication that Moscow has decided whether or not to sabotage the plant, but it does indicate Kremlin military planners are keeping the option on the table.

Why would Russia blow up the plant?

If Ukraine’s troops were to break through Russian defensive lines in the south, then sabotaging the plant could help to slow or stop the advance.

Blowing up the plant would force Ukrainian troops to deal with the fallout – which would almost certainly affect several major cities – rather than continue their attack.

The effects of the fallout could also deny Ukrainian troops an avenue of advance for future attacks.

Or Russia could stop short of causing an explosion.

Setting in motion events that would lead to disaster – such as turning off power to the cooling systems – would force Ukrainian troops to divert to deal with it, slowing them down.

Russia may also reason that threatening destruction of the power plant may be enough to force Ukraine to alter its battle plans to avoid the area.

Moscow could use the threat of disaster at the plant as a way to pressure Ukraine’s western allies, without having to resort to nuclear weapons.

The possibility that Russia may manufacture a radiological incident at the power plant to spoil a Ukrainian offensive should not be disregarded.

What would be the fallout from the disaster?

While the Chernobyl nuclear disaster looms large in people’s minds, the effects of a disaster at Zaporizhzhia would likely be in line with what happened at Fukushima.

In that incident, an earthquake and tsunami caused the meltdown of several reactors at the Japanese plant and an explosion which breached one of the containment buildings.

Though not on the scale of the Chernobyl blast of 1986, it still resulted in the evacuation of 100,000 as a result of radioactive contamination in the areas around the reactor.

In the case of Zaporizhzhia, the nuclear plant is located less than 10 miles from the city of Nikopol which had a pre-war population of 115,000 and would almost certainly be affected.

The city of Zaporizhzhia itself is less than 35 miles away and housed 750,000 people before the war, while Dnipro and Kryvyi Rih – which together accounted for some 1.5million people – are within a 70-mile radius.

Experts have previously warned that prevailing winds at the plant could easily carry the fallout into Russian-occupied areas, and potentially into Russia itself.

A new Chief Twit has entered office.

Elon Musk confirmed that NBCUniversal ad executive Linda Yaccarino will become Twitter‘s new CEO on Friday.

The tech mogul also heralded a transformation of the company into X,  Musk’s long-cherished moniker for an ‘everything app’.  

‘Looking forward to working with Linda to transform this platform into X, the everything app,’ Musk tweeted. 

But how much of everything will X be? And why ‘X’ exactly? Here’s what we know about Musk’s X plans. 

Musk has been fixated on the brand potential of X.com since at least the late 1990s, when he launched the site as an online banking start-up with co-founder Greg Kouri, a real estate developer and friend of his parents. 

But Musk lost control of X.com once the start-up merged with its fierce e-payments rival Confinity in 2000 — creating PayPal, and minting his fortune, in the process. 

Back on July 5, 2017, Musk repurchased the X.com domain from PayPal, explaining it had ‘great sentimental value’ to him.

Clearly, of course, Musk also sees great monetary value in X, hoping the symbolic weight of the infinitely changeable mathematical variable will help him build the ultimate app for all modes of human interaction. 

Payments  

This time last year, at the All-in Summit, Musk waxed admiringly Tencent’s WeChat, a colossal Chinese social media app that offers messaging and video chatting, video games, photo sharing, ride services, food delivery, banking, and shopping.

‘If you’re in China, you kind of live on WeChat,’ Musk has said. 

‘It does everything — sort of like Twitter, plus PayPal, plus a whole bunch of things, and all rolled into one, with a great interface. It’s really an excellent app, and we don’t have anything like that outside of China.’ 

With recent expansions to payment features on Twitter, it’s clear that Musk’s vision for X.com is sure to be an American rival to WeChat offering a similar buffet of internet services and features. 

Phone and video calls 

Earlier this week, Musk tweeted that new features enabling voice and video chat via users’ Twitter handles are currently in the works

Musk said Twitter users would soon be able to ‘talk to people anywhere in the world without giving them your phone number.’ 

The move could help Twitter compete with its social media rival Meta, which offers video chat services via Facebook Messenger and WhatsApp to its billions of users across the globe.  

Comparatively, Twitter had a reported 238 million monetizable daily users last July.

It’s clear that Musk has been gunning for WhatsApp’s market share, ever since the billionaire said the messaging service ‘cannot be trusted’ in response to claims by Foad Dabiri, Twitter’s current director of engineering. 

Dabiri had tweeted that WhatsApp had accessed his phone’s microphone while he slept.

Broadcasting and newsletters 

Under Musk, Twitter has already attempted to crowd into the paid newsletter space, sparring with market leader Substack and offering payment and subcription services to aspiring content creators.

But that’s only one step in Musk’s ambitions to expand Twitter as a media destination and not just a microblogging platform for discussing media elsewhere.

Although Musk has publicly stated that he did not ink a deal for former Fox News host Tucker Carlson to bring his show to Twitter, it’s clear that he had been encouraging media figures to do so on their own funding and initiative. 

Musk tweeted at ousted CNN host Don Lemon: ‘Have you considered doing your show on this platform? Maybe worth a try. Audience is much bigger.’

Dating next? 

Whether Musk was being serious or not, he has entertained his fans calls to add dating app features to the service, which YouTuber Steven Mark Ryan proposed as a solution to Musk’s concerns over declining birthrates.

‘Interesting idea,’ Musk responded, ‘maybe jobs too.’  

Although other social sites, including Facebook, have taken a stab at entering the dating app space, none have made a dent in market behemoth Tinder, which boasts having created 55 billion matches within eight years.

By comparison, since launching in 2019, Facebook Dating claims it had created over 1.5 billion matches in 20 countries.

Arguably, there’s no loftier, more difficult ambition than delivering ‘everything.’ 

But that’s exactly what X would have to achieve to succeed, crowding out rivals in multiple spaces, like dating apps, where market dynamics are already mature.

Sentimental value is one thing, but for X.com to rise again it’ll have to be more than just a passion project.