The Universe: Fiery Objects Plummet to Earth (S4, E3) | Full Episode | History

in the beginning there was darkness and then  bang giving birth to an endless expanding   existence of time space and matter every day  new discoveries are unlocking the mysterious   the mind-blowing the deadly secrets of  a place we call the universe they appear   out of nowhere and threaten our very  existence from rocks crashing through homes   to mount everest sized boulders triggering mass  annihilation no one is safe from their wrath and   some of these intruders are not extraterrestrial  they're actually man-made cosmic junk   take cover as we investigate meteorites and space  debris the deadly stuff that falls from space 11 39 p.m october 6 2008 the  catalina sky observatory in arizona   notices something it hadn't seen before an asteroid the size of an suv  is screaming down towards earth   at over 000 miles per hour an alarm sounds  throughout the international scientific community is this asteroid on a collision course with  earth this object was special because it   was probably going to impact the earth  and over the course of the next 21 hours   500 observations were made of the object  to try to exactly calculate its orbit   at nasa's jet propulsion laboratory steve  chesley gets the urgent wake-up call   everyone wants to know when and where this rock  will touch ground they sent me the data i rushed   into the office rather excitedly and spent the  next couple of hours trying to get my arms around   the problem by running the numbers and i reached  the conclusion it was a 100 chance of impact chesley calculates the collision will occur  in less than 13 hours approximately 5 45 a.m   eastern african time its target  the nubian desert in northern sudan   we hadn't really expected or anticipated discovery   of an asteroid that was going to hit the  earth before impact with time to react and   time to predict the location of the impact is  very extraordinary never never seen it before it was countdown to impact with no  time to stop this runaway space rock   emails went out to alert those  on the ground and in the air   5 45 am the moment has arrived a  commercial pilot is flying over sudan   he witnesses a fireball smack right into the  earth's atmosphere with the energy of about   a thousand tons of tnt as it entered the  atmosphere it started to burn and brighten at some point the stresses on the body became  so fantastic from the atmospheric pressure   that it just exploded that explosion  would have sounded like a sonic boom   on the ground 23 miles below   sudanese people returning for morning  prayers hear the frightening sonic roar witnesses see a brilliant fireball followed by  mysterious flashes of light streak across the sky   scientists had hoped the asteroid wasn't  heavy enough to completely penetrate   through the earth's atmosphere  and wreak havoc on the ground satellites track the fiery explosion but there  is little indication that any fragments survive   so there is a possibility that people  could be frightened by such an event   but the risk of injury is really very low  from something so small and steve was correct   there were no reports of injuries or damage  due to falling debris in the remote region planet earth was spared from a potential  disaster partly because the region was so remote   the impactor was small but  the story doesn't end here december 2008 astronomer peter yeniskis  organizes a search and recovery team from   the university of khartoum in sudan  he's determined to find the unlikely   meteorites the surviving fragments  of the asteroid named 2008 tc3 we had a busload with students who were all  eager to go and search we drove 29 kilometers   into the desert to go through the area close to  the explosion to look for the smaller pieces that   might have survived the meteorite hunter's  only guide is a map of the nubian desert   with the projected approach path of the  asteroid they basically used my trajectory   in the ground track that i had laid out on  the desert floor as a guide for their search lined up everybody about 20 30 yards apart   and then started walking down the desert in  line searching for things that were black but spotting small charcoal-like  stones on the rocky desert surface   is akin to finding a needle in a haystack as the  sun begins to set on the first day the team is   about to walk away empty-handed when a student  suddenly comes forward with a suspicious rock   a student called muhammad alameen had this  little rock in his hand that was clearly a   meat white it had a beautiful black fusion  crust around it and it was undoubtedly a   metroid and then everybody started being excited  and shouting and singing and waving their hands 280 meteorite samples were eventually recovered  equaling 11 pounds which for planetary scientists   was like hitting pay dirt this was one of the  meat rights that was recovered uh not much bigger   than this we think that a lot of these meat rights  when they came out of the explosion were tumbling   very rapidly and that resulted in breaking of  the meteorites when it was still up in the air   2008 tc3 is the first asteroid ever observed  in space which was later found on the ground   scientists are calling it the first  asteroid sample return mission   it's the first time that we've actually detected  something in space figured out that it was going   to hit the earth figured out where it was  going to hit the earth and we actually saw   it hit the earth we've even recovered pieces of  it that's remarkable this whole experience was   really fantastic for us this was an excellent  test for what we're really preparing for which   is the possibility of having to deal with  a larger impactor sometime in the future planet earth may not be so lucky the  next time scientists now suspect 2008 tc3   came from a piece of a much  larger rock from the asteroid belt   a region between jupiter and mars where  asteroids and comets take up residence in this crowded galactic neighborhood these fossil  relics from the formation of the solar system   occasionally collide with each other and  explode into smaller pieces it's these fragments   that can migrate towards earth a bullet  can provide a pretty good stand-in for   one asteroid striking another in terms of its  impact speed asteroids in the main asteroid belt   will run into each other at speeds of over 11  000 miles per hour now a bullet traveling out   of a rifle can be a good analogy for that because  they will leave a rifle barrel at speeds you know   maybe a fifth that so it doesn't just fragment  it literally blows itself to pieces okay we'll   head down range and actually uh set up our little  artificial asteroids at a safe enough distance to   shoot since real asteroids are hard to come by  we're going to use a couple of stand-ins today   these bullet impacts are comparable to the  collisions in the asteroid belt let's see   what our results are here this is actually  rather typical of the results of an asteroid   impact where you tend to have a few large pieces  of debris several medium-sized pieces but nature   is very good at making lots and lots of little  debris these little kilometer size fragments   are what we actually see today as the near-earth  asteroids these fragments which have worked their   way in from the main asteroid belt approaching  the inner solar system passing near our planet   sometimes impacting our planet these near-earth  objects or neos have transformed our near space   environment into a danger zone the speeds with  which objects are running around in the inner   solar system is uh it's much akin to actually  a bunch of cars driving crazily down a highway   the vehicles themselves are traveling at high  speeds when they cross lanes without looking and   perhaps running into each other they're hitting  at equally high speeds and that's kind of like   objects moving on their own independent orbits  around the sun every few hundred years earth gets   hit with rocks the size of a football field that  can destroy entire cities but every half million   years we get struck with boulders the size of  mountains that could ignite global disasters the earth's atmosphere a layer of gases  surrounding our planet incinerates most material   but occasionally larger heavier objects slip  through as soon as they enter the earth's   atmosphere they get slowed down decelerated by the  atmosphere and they lose pretty much all of the   velocity with which they entered and during  that time is when you see the fireball event   but once they lose that  velocity that they came in with   they essentially just fall pretty much at  terminal velocity onto the earth's surface when asteroids hit the earth's atmosphere they  become meteors bright fireballs in the sky if they make it to the ground  they're called meteorites over the past century alone meteorites have  struck homes vehicles and even people in 1954   an eight-pound meteorite crashed through  the roof of a home in sylacauga alabama   and hit a woman in the hip  leaving her with nasty bruises in october 1992 amateur videos caught a fireball  flashing across the skies above several atlantic   states the 27-pound meteorite eventually crushed  the back end of a car in peekskill new york in november 2008 a police dash camera recorded  a bright meteorite explosion in the skies over   alberta canada these caught on video impacts  prove that things really do fall from the sky what's even more startling is the physical  evidence of much bigger impacts ones that   have caused global catastrophes in the past and  may ignite a cosmic armageddon in the future earth was not always an ideal  address for human beings during its infancy 3.8 billion years ago the  third rock from the sun was a cosmic war zone   during this brief period called the late heavy  bombardment billions of leftover debris from the   formation of the solar system pummeled our planet  at rates up to 20 000 times higher than today what happened is that jupiter and  saturn the two giant planets in our   solar system went into what's called a  gravitational resonance with one another   so jupiter made two complete orbits around  the sun for every single orbit made by saturn   and when that happened it rearranged the  entire solar system it reshuffled uranus   neptune jupiter and saturn and moved the  giant planets farther out when that happened   that just sent a volley of comets and  asteroids rocketing into the inner solar system at the same time these rocky bodies help to  mold our baby planet to the shape it is today here are the battle scars only 170  impact craters are still visible on earth   weather water and plate tectonics have  erased most traces of ancient cosmic violence   but proof of earth's tumultuous past lies on  the moon which was formed at the same time but   lacks plate tectonics and other erosion processes  that tend to erase the evidence the earth itself   has been bombarded every bit as much as our nearby  moon if you look up at the moon in the sky and you   see its cratered surface you have to imagine our  own earth cratered and battered to at least that   degree and in fact because we're a bigger target  in space even more by counting craters on the moon   scientists can learn about the number of  impacts on the nearby earth past and present   scientists can learn about the sizes and  compositions of asteroids that impact the earth by   studying the characteristics of the craters that  they create so we're going to try and demonstrate   that today by tossing some weights into the sand  on the beach here and we're going to see if we   can come up with a relationship between the size  of the weight and the size of the crater that it creates based on my measurements i calculate that this  beach was impacted by three rocks ten inches   in diameter five rocks that were six inches in  diameter and eleven two inch diameter rocks this   technique of measuring the size and frequency  of craters on this beach is very similar to the   technique that scientists use to understand the  frequency of impacts throughout earth's history   today the best preserved impact craters  exist in dry desert regions around the world   meteor crater located near winslow arizona   is one of the lasting reminders of the destruction  caused by objects from space and scientists are   just cracking the surface of understanding  the repercussions of these ferocious events okay lights okay do we want  to back one off to 250 000 planetary geologist pete schultz formulated a  new experiment to simulate what impact craters   look like under the surface 1.1 feet at the  vertical gun range at nasa's ames research center   schultz is using a massive 30 caliber light gas  gun that shoots projectiles at various targets   inside a vacuum chamber today we're going  to try to look inside a crater as it farms   and to do this we're going to use a clear block  it's transparent so we actually get to watch the   crater as it grows but from the inside rather  from the outside this little bead is simulating   an asteroid that's going to slam into the  surface of the earth so let's get inside we're in the impact chamber  this is where everything happens   projectile bead is going to be coming  in at around four miles per second   we're going to hammer this transparent  block we're going to be looking at   everything that happens below the ground when  an asteroid hits the surface of the earth outside the chamber high-speed cameras will  document the deep impact from various angles uh   the shimatsu is all up down there in the control  room schultz watches the monitor with nervous anticipation high voltage the vertical gun launches the glass  bead projectile into the acrylic block   sweet wow okay that is just freaking gorgeous  the experiment was a smashing success   pow so here we actually have the impact but  now we see this vapor plume this is really hot   gas it's about a temperature close to the  surface of the sun and then as it moves   away it cools and now we begin to form  the crater with the ejector coming out   and we're now watching the crater  actually begin to form on the inside that that is awesome okay i'm gonna see i'm  gonna see what we did oh man did we bust this up now we can look to see how these cracks develop  through time so if this were a big impact   these cracks would grow where the entire  crater could then collapse inward and fail impact experiments at the vertical gun range  shed light of a large scale destruction caused by   asteroids that have fallen from space when we see  an impact it's not just the cracks and cracking   you will also see the vapor plume expanding that  affects life that affects survival if this impact   occurred on earth and was large in scale it would  simply fry the atmosphere it would send debris   out and as it hits the earth again  it would cause more devastation   scientists have discovered that impacts  from space have affected the evolution   of life on earth we know that in fact the  flux of meteorites hitting the earth was   much higher in the past than it is today and in  fact there have been known instances for example   the large impact event 65 million years  ago at the cretaceous tertiary boundary 65 million years ago an asteroid  the size of mount everest   struck the yucatan peninsula in mexico with  the energy of a 100 million megaton bomb it created a hundred mile wide crater underwater  that was finally discovered in the 1980s   scientists have determined that the  asteroid impact ignited atmospheric events   that may have led to the mass extinction of 75 of  all prehistoric species including the dinosaurs there were a lot of potential effects  that could have led to the extinctions   heating of the atmosphere for instance  by the ejecta perhaps leading to   wildfires the poisoning of the atmosphere from  the gases produced from the vaporized asteroid   it was every ecological disaster you could think  of all happening at the same time but was this the   last time an asteroid triggered a mass extinction  a controversial new theory suggests a space rock   was responsible for the disappearance of  the ice age mega mammals of north america scientists are dying to know  what happened 13 000 years ago the ice age was slowly ending the north  american continent was inhabited with big   beasts like the woolly mammoth mastodon  giant ground sloth and the short-faced bear   but something caused 35 major groupings of  species to vanish from the fossil record   many think the ancient clovis people a hunter  and gatherer society killed off the mega mammals   but startling new evidence  suggests that an object from space   may have led to the demise of the giant creatures thirteen thousand years ago the climate  change suddenly rapidly and dramatically   it looks like there was some  type of extraterrestrial event   whether it was a large meteorite an asteroid  or a comet exploding in the atmosphere   and all of a sudden the planet was  thrown back into a little ice age north america experienced a brief  return to ice age conditions   so could there be a connection between this cold  snap and the disappearance of the mega mammals archaeologist ken tankersley claims to have  dug up evidence of a possible cosmic impact   in sheridan cave located in cary ohio it's one of only 12 known sites that  have been precisely dated to the time   of the late pleistocene extinction  which was the end of the last ice age in this deep cavern tankersley and his  team have discovered the burned remains   of more than 60 species of plants  and animals from that time period   including hunting weapons of the clovis culture  i don't believe it this is a clovis bone point   it's manufactured from a mega mammal rib probably  a large animal such as the american mastodon   what's fascinating about this specimen  is the person who manufactured this   likely witnessed the event 13 000 years  ago tankersley says that most of the bones   he's uncovered underwent intense burning that  couldn't have been caused by a mere forest fire   he says it had to have been from a colossal  explosion the kind generated by an earth impact and the archaeologist says he's found the  smoking gun oh look what we have here it's   hidden in a dark geological layer of dirt  called the black mat which dates back to 12   900 years ago this layer has been uncovered  in more than 50 locations in north america note this black area let's see if i can travel  through here and bring out some of the more dark   areas oh nice we're literally at this spot  looking at the contact of the end of the   last ice age and this oxidized layer above  it this is where the omega mammals go extinct within this sediment layer some scientists claim  to have found key pieces of evidence that point   to a cosmic impact carbon sparrules created by  intense fires shocked diamonds formed through   extreme temperatures and pressures lonsdale lights  rare hexagonal shaped diamonds that are only found   in meteorites and micrometeorites miniscule pieces  of iron and nickel that come from outer space   if we take a magnet and run it across this  oxidized layer my guess is we'll probably   pick up micro meteorites you can see how the  sediments adhering and just as the magnet picks up   iron from this layer so does the magnet  adhere to this meteorite and this suggests   because we have a high concentration of micro  meteorites in this layer and a complete absence   above or below and it's at the event of 13  000 years ago something dramatic occurred here we know that all over north  america there is a thin layer   of dust and particles just  before that black matte form   that indicates that something happened right  before the event that is the climatic change   what is it we still don't know exactly all we know  that something happened to date no impact crater   has been found but a space rock doesn't have to  reach the ground to generate mass devastation in 1908 a rocky body slammed into the atmosphere  six miles above siberia's tunguska wilderness   it released energy yielding about five  megatons of tnt you can imagine what it   feels like to do a belly flop off of a high  diving board and you smack into the water   a small weak rocky asteroid will kind of  undergo a similar sort of feeling as it   very quickly is decelerated and  break in the dense lower atmosphere   immediately after the tunguska airburst  impact an intense shockwave and hot air blast   travel to the ground and spread outward it  engulfed almost a thousand square miles of forest   some scientists proposed that a similar scenario   may have contributed to the extinction  of the north american mega mammals   and a comet not an asteroid may have been  the culprit unlike asteroids these dirty   snowballs contain more ices and gases that  tend to break up before reaching the surface when the theorized comet came down into the  earth and would have exploded in the atmosphere   it would have distributed amongst the ejecta that  was created beneath it it would also have seen a   great variation in the deposits left behind there  would have been intense burning over a large area   anything within the impact zone of course would  have been devastating at the same time however it   would not have had immediate impact for the rest  of the planet just within the impact area itself   this so-called clovis comet theory  suggests that profound climate changes   led to the eventual extinction of  the mammoths from north america   however contrary to popular belief a small number  actually survived in various regions of the world   up until around 2000 bc and archaeological  evidence indicates that the clovis culture   didn't go extinct from this alleged impact  rather they adapted to their changing environment when the large game animals that clovis  people were hunting disappeared from the   landscape people had to change the way  in which they were hunting and gathering we may never know with certainty whether  a near-earth comet caused the clovis event   but would modern man learn to survive after an  earth impact we may eventually be put to the test   at this very moment meteorite  scientists scour the landscape   in search of these messengers from the sky these  space rocks hold clues to impacts of the past   and as scientists are now discovering  clues to what is coming in the future mass extinctions mile wide craters scorched  landscapes all created by objects from space   meteorites have been intruding on our planet  since the formation of the solar system   so where do we typically find these rocks  most meteorites they're more easily found   in dry desert regions of the earth for example  in the saharan desert or even the cold deserts   like antarctica where there's not a whole lot  of vegetation or there's not a whole lot of   other rocks to confuse you however meteorites  fall everywhere on earth with equal probability   cosmo chemist menakshi wadwa has traveled  the world in search of meteorites   and now oversees the largest university-based  meteorite collection in the world we're here   looking at the collection of meteorites in the  center for meteorite studies at arizona state   university there's basically three different kinds  of meteorites you can have stony meteorites stony   iron or iron rich meteorites but all three kinds  have at least some amount of metal and so you   can distinguish terrestrial rocks from meteorites  by the content of metal and meteorites the other   way to actually distinguish a meteorite from  a terrestrial rock is that you'll actually see   a fusion crust on meteorites that forms on  these objects when they're falling through   the earth's atmosphere most of the meteorites  recovered originated in the asteroid belt   between jupiter and mars but nearly four dozen  actually came from our moon and the planet mars   the idea there is that you probably had a large  asteroidal body that impacted the moon or mars   and ejected pieces of the crust of the monomars  and these ejected pieces probably fell into these   unstable earth-crossing orbits and eventually  pieces made their way to the earth that way   this is a piece of a lunar meteorite and we  believe it came from the highlands portion   of the moon and we know that this is actually a  lunar meteorite because we can compare this with   actual samples that were brought back by the  apollo missions in the late 60s and early 70s   meteorites are precious research subjects although  they've destroyed life time and time again   they may also have provided the  chemicals needed for life on earth   this is possibly one of the most well-studied  meteorites in the world it fell in 1969   in mexico and an interesting thing  to note about this rock is that these   white grains are possibly some of the oldest  solids that formed in our solar system as our   solar system was forming four and a half billion  years ago these white grains combined with the   atmospheric chemicals and organic compounds on  earth may have formed a mixture of amino acids   the essential elements of life so meteorites  have played a very important role in   possibly the formation of life on our planet and  certainly the evolution of life on our planet   meteorites may have once provided the  necessary components for living things   but they can be a source of grave concern when  they hurtle down from space without prior warning   september 19 2007 a fiery meteorite  streaked down from the sky   and impacted the soft soil near the peruvian  town of carrancas which borders bolivia debris   flew over 600 feet as the meteorite left a  crater over 15 yards wide and 15 feet deep there was a gentleman riding a bicycle and he  was knocked over another person looking the   other direction quickly turned around and saw  this thing hit with a large plume rising above in talking with the locals of villagers they  had no idea except they thought maybe this   was some form of military action you know  they're very close to the border of bolivia   scientists reassured the locals that a meteorite  and not a missile caused the impact crater   but immediately after the event many villagers  complained about headaches and vomiting they   literally became ill most likely because of sulfur  or because of the fine dust that was inhaled the   vapor probably came from the material that was  following the meteorite as it was coming through   it was melting it was vaporizing  as it passed through the atmosphere   and it probably wouldn't hit cause  some additional release of gas   but could a space rock actually  deliver harmful elements to earth   sci-fi movies and conspiracy theorists  have proposed that meteorites could   seed our planet with lethal bacteria or  viruses but what's fact and what's fiction   the probability of this happening is very very  very small if that rock made it to earth and   somehow that microbial life form survived it  would find our atmosphere very toxic any microbe   that evolved in an anaerobic and a non-oxygen  environment is not going to survive long in oxygen the possibility that the peruvian meteorite  committed cosmic biological warfare   is remote but had this small stony meteorite  impacted a nearby village the aftermath would   have been much different this would look like  somebody had planted a roadside bomb it would   have had that effect it opened up a hole so  large that would have swallowed several cars   the peruvian meteorite impact once again  illustrates the unpredictability of things   that fall from the heavens and space rocks aren't  the only objects that can cause bodily harm   up to 200 heavy objects hit our planet each year  and they're not extraterrestrial they're man-made the space shuttle columbia was about to conclude  its mission in space when disaster struck   the vehicle disintegrated during  re-entry into earth's atmosphere   debris fell over texas louisiana and arkansas  all seven crew members perished because of   reentry heating it got hotter as it came into the  atmosphere some critical components failed that   caused an overall failure of the entire spacecraft  which spread debris over a large footprint spacecraft re-entry disasters are rare but space  debris is not since the beginning of the space age   rockets have carried thousands of  satellites into orbits around our planet   as a result we've littered space with spent  rocket stages defunct satellites fuel tanks   as well as nuts bolts and fragments from  collisions and explosions with other debris this abandoned space debris hovers over  our planet like a cosmic garbage dump   and some will eventually fall back to  the earth the question is when and where   things that re-enter the  atmosphere they do have a risk   the real risk is that something falling through  the atmosphere will hit a person on the ground 5400 tons of space junk is already crash-landed  on earth in 1979 skylab the first space station   scattered debris across the indian  ocean and parts of australia   in 1997 a dvd sized piece of  smoldering metal fell from the clouds   and brushed the shoulder of  a woman near tulsa oklahoma   she wasn't injured but hundreds of  miles away this 570 stainless steel tank   landed next to a farmer's house in texas both were  pieces of debris from the same stage of a delta   ii rocket it's a piece of debris from a launch  stage that was in orbit for about nine months and re-entered over the northern  part of the united states and canada came down and left several fragments of  debris around this was the largest piece   at the aerospace corporation in el segundo  california scientists study space debris   to find out what materials survive reentry  and why and how to minimize future hazards   this is remnants of a stage that  put a gps satellite into orbit   this was found in saudi arabia  this one is made out of titanium   which is a very high melting point material  and that's one reason why this one survived so   nicely and this was traveling again on the order  of probably 150 miles an hour and hit the ground why do objects fall back to earth   most space debris resides in low earth orbit  approximately 600 miles above our planet's surface in space objects can stay for tens to hundreds  of years because there's no air resistance   but they will eventually undergo orbital decay  they will lose energy because there's very little   atmospheric drag and the earth's gravity  will tug them back down into its atmosphere   satellites fall back sometimes quickly and  sometimes over a long period simply because they   begin to touch a little bit of the  atmosphere enough of the atmosphere   that there's an increasing force over a long  period of time and that small force acting   over a long time will basically drag them out  of orbit and they will eventually re-enter most debris burns up during atmospheric re-entry  and vaporizes however some pieces are made of   stronger components such as stainless steel  and titanium which can survive tremendous heat once below the dense regions of the atmosphere  they literally free fall to the ground it'll hit at a very low velocity say 150 feet per  second or 150 miles an hour something like that   and so that's the problem so you're basically  slowing something from an orbital speed   down to essentially nothing  in a relatively short time   main engine start the international space  community now imposes new design requirements   for most objects including a propellant system  to ensure controlled re-entries over water   basically the international community has agreed  that an acceptable level of risk for a re-entry   is around one in ten thousand that means that if  you did a particular re-entry ten thousand times   the likelihood is that you'll hit one person on  the planet and so if you exceed that threshold   the objective is that you should re-enter that  piece of hardware into a safe area like the ocean but new guidelines won't have any effect  on the thousands of pieces of old debris   already in space unfortunately we have a  number of objects in space still which were not   designed when that requirement  was around and they still are   slowly coming down so it'll be a while  before some of these things take effect it's no longer a sci-fi fantasy extraterrestrial  and man-made things continue to fall to earth   we constantly need to search the skies for  objects that could decimate a neighborhood   or even worse and human civilization you

Channel: HISTORY

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Keywords: history, history channel, history shows, history channel shows, the universe, history the universe, the universe show, the universe full episodes, the universe clips, full episodes, the universe season 4 episode 3, the universe s4 e3, the universe s04 e03, the universe 4X3, watch the universe, Watch the universe full episodes, Season 4, history clips, history channel full episodes, universe, the universe season 4, Fiery Objects Plummet to Earth, natural and manmade plummet

Id: rJxoWjOgu8k

Length: 44min 46sec (2686 seconds)

Published: Mon Jan 11 2021