Predicting The End Of The World | Naked Science

planet Earth 4 and 1/2 billion years old a solid ball of rock weighing 6 trillion trillion tons we are on a quest to destroy it using Cutting Edge physics and planetary science we will explore what could destroy our planet completely a black hole it might seem harmless but its gravity is strong enough to destroy the entire planet Earth a collision with the sun and before you know it the Earth is falling into a fiery plumet a huge antimatter bomb poof okay had a huge Annihilation a giant rock from space you wouldn't want to be standing here 50,000 years [Music] ago or perhaps a swarm of self-replicating robots this has been a a nightmare of [Music] sci-fi these ideas may sound like science [Music] fiction but they're all grounded in proven scientific [Music] fact our planet is seriously tough it has survived everything a hostile Universe could throw at it for 4 and2 billion years yet in the past few decades we have developed Technologies so powerful that some people fear we could literally destroy the Earth it's time to find out if they're right six top scientists are about to reveal what it would really take to destroy an entire planet our first candidate is a black hole the greatest destructive force in the universe a black hole is what's left when a giant star collapses in on [Music] itself the result gravity so strong that nothing can escape not even light soon we may be able to create black holes right here on Earth physicists use huge particle accelerators to try to recreate what happened after the big bang but when they smash particles together they also risk creating a black hole [Music] think of a black hole as Niagara Falls and the water going over like space getting sucked in this unfortunate kayaker has gotten Too Close just like a star getting too close to a black hole Dr Phil plate astronomer and author the water going over the lip of the waterfall is just like space itself falling into a black hole if you're kaying no matter how fast you paddle once you go over that lip you're going down that's the point of no return and it's the same thing with a black hole no matter how fast you try to get out it's going to take you down the gravity in a black hole is fundamentally different from the gravity we experience in normal life normal gravity gra it you can escape from at least in theory cosmologist and golfer Professor lorrence Krauss it's commonly said that what goes up must come down but that's not always the case for example if I hit this golf ball here and I hit it well it would go Fairly far but it would still come back down to earth if I hit it harder it would go further and still come back down but if I hit it with a speed of 5 m per second it would escape from the Earth's gravitational field but for the ball to escape from a black hole it would have to move faster than the speed of light and that is simply not possible what goes into a black hole planets or even Stars never comes out our small planet wouldn't stand a chance for anyone looking for a way to destroy the Earth black holes are a good place to start the trouble is there are none close by enough to do the job unless we make one that's where the atom Smashers come [Music] in with a lot of math and a gigantic machine physicists can now generate atom-sized explosions that may be powerful enough to create microscopic black holes they are trying to study the Big Bang the force of the impacts recreates the particles that made up the universe in its earliest moments some of those particles May create microscopic black holes that doesn't mean our planet is doomed in theory black holes this small would just evaporate like tiny soap [Music] bubbles to destroy this you need something bigger lock holes come in all sorts of different sizes for example at the center of our galaxy there's a black hole of 1 million solar masses if you took the mass of our sun and compressed it down to be a black hole it would be the size of a large American city like Phoenix here on the other hand if you took something like this mountain here which is maybe a million tons and made it a black hole it would be smaller than the size of a single Atomic nucleus somewhere along that scale black holes get powerful enough to cause serious damage to destroy the Earth it turns out you need a black hole that weighs about the same as the earth the earth is 8,000 M across but a black hole weighing that much would be the size of a marble Professor Clifford Johnson physicist here I have a marble siiz black hole it might seem harmless but its gravity strong enough to destroy the entire planet Earth what would eventually happen is that it'll start sucking things in slowly at first and then it will grow in size it will grow and grow and grow until it swallows the whole earth to imagine what that marble would do to the Earth picture what it does to a physicist the gravity is much stronger on one side of an object closer to the black hole than it is on the other side of an object producing an effect that's called spaghettification as that object is stretched out and pulled apart as it falls into the black hole a big enough black hole could do this to our whole planet there's no way even the most powerful Atom Smasher could make a black hole hole this big to destroy the Earth we need to find one [Music] readymade astronomers think there are 10 million or so black holes in our [Music] galaxy if one of them strayed into our neighborhood it could rip our planet to pieces Earthbound telescopes may not even detect it humans would only know it was approaching when its immense gravity triggers huge floods and earthquakes as it plunges into our atmosphere the black hole acts like a vacuum cleaner sucking with a force over 1 and a half th000 times Earth's gravity then it begins to distort the shape of the whole planet Earth's surface stretches and tears apart finally the hole hits and flies straight on in Heating and vaporizing matter as it [Music] goes it starts to orbit the earth inside the planet itself all the time devouring everything in its path gradually the orbit slows the black hole spirals down into the Earth's core eventually it eats the entire planet all that's left is the black hole itself it's a devastating end for planet Earth but fortunately for us it's unlikely ever to happen if you want to destroy a planet black hole is a great way to do it but the problem is it depends on the kind of black hole a microscopic black hole would just pass right through the Earth and it really wouldn't do that much damage a black hole with the mass of the Earth would be about the size of a marble and that would do a considerable amount of damage passing through the Earth but again it might not destroy the planet if you want to do the job right you need a stellar Mass black hole something with about three times the mass of the Sun that thing would come in and it would tear the Earth apart and Gobble down the pieces and it would be game over the problem is we don't know how to make any of these black holes technologically we just can't do it and with a naturally existing one we don't know how to move them so there's got to be a better [Music] way so if black holes don't work time for a new approach one Surefire way to destroy the Earth is to change its distance from the Sun move the planet closer and it bakes move it out and we freeze sending us into another Ice Age scientists have recently begun to realize that moving a whole planet might actually be possible in fact we use the same principle to slingshot space probes around the solar system planet Earth could be just a few well-placed flybys away from a fiery death what would it take to incinerate an entire planet answer a nuclear furnace nearly a million miles across it sounds crazy but the truth is this will happen it's just a matter of time as the sun gets old older and older it's going to actually get brighter and brighter and within about 2 billion years the earth will be in an uninhabitable Zone it'll be like Venus there'll be a runaway greenhouse effect all the water on Earth will be destroyed and the surface temperature will be about 1,000° eventually the sun will swell and Scorch the Earth unless we somehow move the Earth away from the Sun to save it alternatively if you were sufficiently evil I suppose you could imagine doing exactly the opposite um harnessing sufficiently large objects to transfer gravitational energy to kick the Earth's orbit closer to the Sun easy to say not so easy to do the Earth weighs in at 6 trillion trillion tons pushing something that big is quite a challenge but there is a way it's called gravity assist space probe Engineers use gravity assists all the [Music] time take Saturn's Cassini hyan probe it's the size of a school bus one of the biggest probes ever built to build up enough speed to Flame the probe out to Saturn it had to swing by Venus twice and earth once each flyby stole energy from the planet and added it to the [Music] probe the probe got a lot faster by altering the planet's course just a little the name of the game we take a rock about a mile or two across and we move it so that it just passes the Earth the right way and it'll steal energy away from the earth the asteroid will go flying off and the Earth will move in toward the Sun but we shouldn't just waste the asteroid when we can recycle it if we're clever we can take the asteroid and have it go toward the planet Jupiter and then if we pass Jupiter and just the right way it'll take that extra energy it stole from the earth give it to Jupiter and then fall back toward the Earth and if we aim everything just right we get a conveyor belt of energy we steal it from the earth give it to Jupiter and then come right back and in fact we can use hundreds or even thousands of asteroids this way continuously stealing Earth's energy and dumping it toward Jupiter and before you know it the Earth is falling into a fiery plummet first you need to catch an asteroid it's as big as a mountain and it's traveling around 10 m a second next you need to attach rockets and boost the asteroid onto the perfect course next repeat thousands and thousands of times very slowly over thousands of years the earth will fall towards the sun right now we're just over 90 million miles mil Away by 70 million the Earth is a superheated desert like Venus then things start to get really bad as the Earth slowly spirals into the Sun a series of events unfolds which unfortunately spells Doom for our planet as the Earth approaches the Sun the atmosphere heats up and blows off and the oceans boil basically turning the earth into a giant Comet but there's worse to come as the Earth gets closer to the Sun the Sun's gravity pulls on the near side of the earth more than it pulls on the far side and the Earth stretches like putty at some point it gets close enough to the Sun that the Sun's gravity can overwhelm the Earth's gravity and it shatters pulverizes our planet the Earth is dead but its ghost could remain a faint ring of material around the Sun Peter ads planetary impact geologist if the Earth or any object gets too close to another object like the sun eventually the tides will rip it apart as that happens it would simply be broken into many small pieces that would then encircle the Sun as if it were a ring the sun would resemble Saturn with its own faint ring of rocks and dust a fiery death and a a ghostly Remnant if you want to destroy a planet this could be the way to go a great way to destroy the Earth is to drop it into the sun let it plummet to a fiery death and we can do this all you need to do is to pass enough asteroids near the Earth in succession to gravitationally drop it into the Sun and we have that technology we know how to move asteroids it's just a matter of getting them on a precise enough orbit to be able to do it maneuvering billion ton chunks of Rock with pinpoint Precision at hundreds of miles a minute is quite a stretch not to mention the amount of time it would take to capture enough asteroids we've tried to crush it and burn it it's time for another plan an antimatter [Music] bomb physicists have been searching for over a century for a theory that unites our understanding of the large scale Universe planets galaxies and stars with what we know of the subatomic World electrons protons and quarks their theories are bringing to light some pretty destructive phenomena one of them could be a world [Music] killer antimatter theorized in the 1920s detected in the [Music] 30s now we can create antimatter in modern particle [Music] colliders and the base ingredient for the biggest explosion possible antimatter is the most explosive substance ever found pound for pound it's far more powerful than even a hydrogen [Music] bomb but antimatter is hard stuff to find everything we see around us out to the most distant galaxies is matter created 13 billion years ago in the Big [Music] Bang it created antimatter too [Music] they look similar in fact they are entirely opposite put them together and they wipe each other out cosmologist Lawrence Krauss now I have a proton here an antira over there has an antiproton and when we bring them together we're going to make an incredible explosion okay let's [Music] annihilate this is what happened to all the antimatter created in the Big Bang it annihilated if we want to use some for a bomb we need to make it ourselves [Music] making antimatter is a bit like firing a gun at a Target if I shoot a gun at a paper Target the paper that flies out of the target is like matter and the hole that's left behind is the antimatter it takes energy to create a matter antimatter particle pair in this shooting range analogy the bullet provided the energy in reality the gun is a particle accelerator like the one it CERN in Switzerland fire protons in a giant tube steer them around with powerful magnets use the same magnets to accelerate the protons to near the speed of light then slam the beam into a block of metal for every million protons that hit you get one [Music] antiproton it's as if Plate's handgun only left a hole once in every million shots in an accelerator you only get one particle any particle pair out of every million collisions or so and so it's really hard to find that one an matter particle floating around it's a lot like coming to Niagara Falls and trying to get that one particle out of all the Mist and that's why it's so hard to create antimatter on a large scale assuming we can obtain enough antimatter the next challenge is to make it into a bomb nothing is more unstable than an antimatter bomb you have to find a way to hold the antimatter without it touching any ordinary matter if it does it will explode so I have a bunch of antimatter above my hand here well it it better not touch my hand because if it does poof okay at a huge Annihilation but worse it can't interact with the air around it because uh the air is made of matter and again you'd get an incredible explosion researchers need a special container to study antimatter and this is it a Penning trap powerful magnet suspend the antimatter in a vacuum so if I want to store this antimatter what I have to do is somehow keep it levitated above my hand which means I'd have to produce huge magnetic fields in just the right way to keep the part charged particles in the antimatter from touching my hand but i' also have to store it in incredibly High vacuum because any air in the container would again cause an explosion and so the energies and and and Technology required to produce those magnetic fields keep that ultra high vacuum would mean that you wouldn't have such a you wouldn't have a small object you'd have to have surround it with massive amounts of Machinery yet for all that trouble an antimatter bomb isn't just Theory we can make antimatter we can capture it and we can store it but where do we plant it for maximum effect if we want to destroy the whole plan Planet the bomb has to go off near the Earth's [Music] core that's nearly 4,000 M straight down further away than London from [Music] DC right now that's impossible the deepest man-made bore hole stops at just 7 and 1/2 miles but what if we [Music] could so far mankind has managed to create a grand total of 20 nanog of antimatter that's a 100 million times lighter than a dime in your pocket so the bomb is going to be too small even to see well 200 ft away in this test range in Arizona we have the explosive equivalent of TNT so let's see how big of a bang that makes wow 20 nog of antimatter makes quite a blast but it's way short to destroy planet Earth we would need 2 and 1/2 trillion tons of the [Music] stuff that's a bomb the size of Mount Everest at the bottom of a hole 4,000 M deep if it were possible the result would split the earth into thousands of pieces with a powerful enough bomb the pieces would fly out into space and are lost with a slightly weaker bomb the pieces fall back under the force of Their Own gravity collapsing into a molten ball an eerie echo of Earth's creation 4 and2 billion years ago it could happen in theory but there are a few technical details to iron out first so what's the matter with antimatter well if you're trying to destroy the Earth it'll work it'll do the job the problem is you need about the energy that the sun puts out in an entire weak so it's a huge amount and we just don't have the technology to create that right now at the present rate of production making the bomb would take more than the age of the universe the other problem is getting it to the Earth how do you do that well you'd have to get it to the Center of the Earth and that means digging a hole several miles across and 4,000 M deep so in the end don't think anim matter is probably the most efficient way of destroying the planet so as a way of destroying the Earth maybe antimatter has some problems but we know the next approach works because it already happened once before in Earth's ancient [Music] past space is a dangerous place it's full of debris rocks the size of Pebbles up to rocks near the size of a planet there are impact craters everywhere including our moon these asteroids can hit us as well an asteroid wiped out the dinosaurs maybe a bigger asteroid could destroy the planet entirely meteor crater Arizona almost a mile across nearly 600 ft deep today science can reconstruct what happened here thousands of years ago Dr Dan Dura planetary scientist you wouldn't want to be standing here 50,000 years ago this iron meteorite about the size of a small office building or so it's made out of stainless steel from space it's about to strike the desert with an impact energy of somewhere between 1 and 10 megatons and it's that energy that's going to excavate and open up this crater behind me which is nearly a mile across the impact ultimately devastated an area the size of New York City with 600 times the power of the Hiroshima bomb and that was small 65 million years ago a real monster struck it was 6 mil across sat on the ground it would out toop Everest by half a mile the crater was over 100 m wide the impact wiped out the dinosaurs and destroyed most of life on Earth an even bigger Space Rock could destroy the planet we're already developing Technologies to protect against future impacts ironically you could use those same Technologies to make an impact happen one approach is to hover a space probe near the [Music] asteroid the probe's mass generates a tiny gravitational pull on the [Music] rock over time that can change the asteroid's course enough to miss the Earth or to guarantee a hit another protection technology that we could use is a technique called solar sublimation this diverts an asteroid or Comet using nothing more than sunlight to demonstrate the effect Dura starts by building a homemade Comet some fraction of nearth objects are comets so let's examine what comets are made out of let's let's actually make a comet take some soil add dry ice then water and some chocolate we'll put in a few perc of organic material into our Comet and of course in the outermost solar system there's a little bit of ammonia here and there we'll let that be represented by this ammonia cleaner let's see if we can pack this up and make ourselves a little Comet nucleus a magnifying lens completes the [Music] apparatus if one were to uh actually Focus the light from the sun onto the surface one could cause some of that that water to vaporize away and just like on this Comet nucleus the jetting action of those evaporating gases act a little bit like little artificial Rocket Motors attached to the object and over time they really do cause it to be pushed slightly off course the power of sunlight alone is enough to divert a space Rock onto a collision course with Earth but solar sublimation may not be effective on an object big enough to pulverize our planet to destroy the Earth our space missile needs to be big like Mars big we know this for certain because it's happened before 4 and A2 billion years ago a rock the size of Mars struck the earth a glancing blow the impact debris created the moon if it had hit head on none of us would be [Music] here we've come here to the vertical gun range at Nasa ases in California for proof this 12T gun fires beads up to 4 m per second six times faster than a rifle bullet Professor Peter Schulz a planetary impact geologist uses the gun to simulate a mars-sized object represented by this small projectile hitting our planet headon [Music] the space environment chamber is ready Schultz makes his final adjustments but will our scale model Earth break apart completely that hurt that really hurt look at this thing just this is worse than a science fiction movie that's that's just glorious disaster there's nothing [Music] left a head-on strike destruction guaranteed so the things that destroy an object is going to be combination of the size of the object the speed of the object and the angle the lower the angle the less likely it'll completely bust it apart so to really destroy the Earth you need something that's humongous and needs to hit straight on now we know what it takes to use an impact to destroy planet Earth asteroids and comets are just too small we need to move something the size of a planet onto a collision course that's a level of Technology we won't be reaching anytime soon now we can move asteroids around and we can move comets around but those are only a few miles across the problem here is that we need something really big Mars is about a third of the size of the Earth and even that hitting the Earth won't destroy it we would need something almost as big as the Earth itself something like Venus and even then we just don't have the technology to be able to move something that big with that kind of precision to aim it at the Earth and blow it up destroying the Earth with a space Rock just isn't going to happen perhaps the killer punch won't come from space but from right here on [Applause] Earth genetics robotics nanotechnology researchers hope machines will lead us to a brave new New World already robots can learn build other robots and cooperate with each other it could be the beginning of a new age it could also be the beginning of the end right now we can only build robots that work with humans in control but science is working towards machines that can think for themselves and even reproduce robots that can make copies of themselves without human control could one day take over the [Music] world hod Lipson professor of Robotics Lipson is a Pioneer in robot replication if this robot could make another robot identical to itself and then those two robots can make four robots and so forth these robots could fill up a space such as this here uh fairly quickly once the first replicate is made there's no stop stopping the process but first we've got to make them at Cornell's robotics lab Lipson and his team already make robots that learn robots that build and robots that build [Music] themselves this is the world's first self-replicating robot Supply it with building blocks and it assembles them to make a copy of itself it needs Lipson and his labex to keep it stocked with plastic cubes so this robot is pretty benign to destroy the Earth we need to develop robots that use smaller blocks and eventually individual atoms we've been trying to make robots made of much tinier cubes uh on the order of half a millimeter and you can uh barely see them there's about 10 of them in this container here we're trying to get these very small units to combine together and the smaller they get the faster and more easy it is to replicate Lipson thinks that advances in robotics will revolutionize design and manufacture but where there's progress there's also danger in theory nanosiz machines could start to rep replicate out of control self-replicating nanom machines could in theory destroy all life on [Music] Earth to destroy the planet itself we need something more to reproduce a robot needs energy and raw materials in other words food the more food there is the more copies our robots can make and the biggest source of food on the planet is the planet itself the ultimate uh kind of self-replicating process is something that's inspired by Nature so if we can have a machine that can essentially self-replicate using resources in the environment food and energy then that would be a pretty big achievement and the biggest natural resource on Earth is Rock design a self-replicate robot that feeds on rock and it has 6 trillion trillion tons of food right under its feet some living creatures already use rock rock feeding bacteria live in the Earth's crust even several miles deep but Nature's Rock eaters are good for the planet they help form soil and keep life ticking there's a whole Suite of Rock eating bacteria that we've now uncovered on the earth which will go and chew up and eat and use the materials in the rocks for their sources of energy and for the sources of compounds they use to build other biologic molecules there are literally biologic organisms that do just this eat rock rock eating self-replicating robots but they've got to be smart they need to cooperate Professor Alan Winfield roboticist in charge of the siman project to design robots that swarm like insects Syrian is a 5-year project to try and build a swarm of self assembling robots perhaps as many as as 30 or 40 will physically join and then behave and act as a single organism the big challenge is going to be how to get the robot to first of all decide what to be a foot bot or a knee bot or a sensor bot or a brain bot and then work cooperatively so that for instance the organism can stand up and walk we can already make robots that reproduce we can make robots that cooperate put them together and at last we may have our planet [Music] killer here's the math say each robot takes one day to replicate then after a single month you have over 1 billion robots after a year you have trillions Earth is covered with machines that do nothing but gobble Rock in the end no more rock just a a huge ball of self-replicating [Music] machines now what a robots made of well iron magnesium aluminum and silicon the same things the earth is made of and so all you have to do is to create one of these self-replicating robots and let it out into the wild it'll make a zillion copies of itself and they will consume the Earth and eventually there'll be nothing left success at last perhaps perhaps not in our quest to destroy the planet we've tried devouring it incinerating it pulverizing it blowing it up and breaking it down planet Earth is a proven Survivor it has taken everything the universe can throw at it for 4 and2 billion years and one thing is certain we're still [Music] here [Music] [Music]

Channel: Spark

Views: 6,060

Keywords: Spark, Science, Technology, Engineering, Learning, How To, education, documentary, factual, mind blown, construction, building, full documentary, space documentary, bbc documentary, Science documentary, space, end of the world, apocalypse, black hole, antimatter, robots, the sun

Id: F8d06iI3J2A

Length: 45min 16sec (2716 seconds)

Published: Fri May 31 2024