"[ Man Narrating ] Two alien warships... battle it out in a ﬂooded meteor crater." "This isn't science fiction." "Fire!" "[ Narrator] It's the beginning of a new kind of warfare here on Earth... with a secret weapon hidden in big history." "[ Explosion ]" "We think of history as a timeline... a series of events stretching a few thousand years into the past." "It's time to think bigger." "Instead of a line, imagine a web of infinite connections... interacting over billions of years... linked together to create everything we've ever known- our universe, our planet and us." "History as we know it is about to get big." "[ Narrator] The American Civil War." "For the first time in the history of mankind..." " two ships" " Fire!" "Made not of wood but of iron" " Fire!" " Meet in battle." "The Monitor... and the Merrimack." "While traditional history tells us that the first clash of ironclads... ushers in a new era of naval warfare..." "Big history reveals an even a bigger story." "How this pivotal moment in human history... connects to the chaos of the early solar system... and the violent impacts from meteors, asteroids and comets... that shape the Earth as we know it... and give us the tools to survive." "Big history links back 35 million years." "This giant meteor, more than three miles wide... is on a collision course with Earth." "When it crashes, it will help to shape America." "The meteor slams into the Atlantic Ocean... with enough force to blast an underwater crater more than 50 miles wide... and as deep as the Grand Canyon." "Over millions of years, the coastline shifts... waters recede... leaving behind a bay deep enough to harbor large ships" "the Chesapeake." "The Chesapeake Bay itself is a gigantic impact crater." "[ Narrator] An impact in just the right location... to make the Chesapeake a critical hub of American history." "The Chesapeake Bay sits midway down the eastern coastline... at the intersection of five major rivers." "A safe harbor that's ideal for building colonies and commerce." "The first English settlers to put down permanent roots in America... do so here in Jamestown, Virginia." "And because the bay is a gateway to America... the power to control it is a prize worth fighting for." "During the American Revolution... both sides see the Chesapeake as the key to victory." "In 1781... the Americans surround the British at Yorktown... forcing a surrender and Winning the War." "Thirty years later, in the War of 1812... the British invade up the Chesapeake Bay... and march on to burn Washington, D.C." "And as North battles South in the American Civil War" "[ Man ] Fire!" "The Monitor and the Merrimack fight to a draw... on the waters of the Chesapeake impact crater." "It's a prehistoric scar ripped into the surface of the Earth." "But the Chesapeake Bay... is just one of almost 200 known large impact sites around the planet." "At 186 miles wide, the Vredefort crater in South Africa... is evidence of the largest asteroid ever to strike the Earth." "Many more impact zones have been erased over million of years... by weather and erosion." "One of the frightening things, once you zoom out and look at a big history point of view... is just how often the Earth has been pounded by rocks." "[ Narrator] These impacts don't just create the contours of our map... meteors create the entire planet." "This is the birth of our solar system." "The sun sits at the center of a debris field." "Over millions of years, the debris clusters together... into space rocks that we call meteors... and ice chunks called comets." "In the chaos of space, they crash into each other... merging and growing into larger clusters." "[ Man ] As one object hits another... the larger object will have sufficient gravity to attract the smaller object to it." "Like a snowball, all this material is brought together, right... into these larger and larger objects." "[ Narrator] Large objects like planet Earth." "Once the planet forms... more rocks crash in... with alien elements that lake hold..." "And threaten to take over." "[ Narrator] Big history is a new way to see the world." "It connects the chaos of the early solar system... to the birth of our planet... and reveals how the scars on the surface of the Earth... that shape our story. -." "Are the results of violent impacts." "Impacts with the power to transform the ground beneath our feet... into the elements we crave most." "As a meteor hurtles to Earth... each ton of rock carries the energy of 100 tons of T.N. T." "Meteor collisions are very serious events indeed... because of the size and power... um, and explosive sort of potential of these collisions." "[ Narrator] Large impacts have enough power to change the Earth's chemistry." "In Siberia... where shock pressure from an ancient meteor... creates the largest deposit of diamonds in the world." "And in Oklahoma... where Ames Crater now sits atop 25 million barrels of oil... because of conditions created by a meteor explosion." "But meteors don't just create valuable resources." "They also deliver them." "Big history connects back... to the Chesapeake meteor crater... and the battle of the Murmur and the Merrimack." "It's the clash of the ironclads... and it changes the way we fight." "[ Markley] it was the end of the wooden ships of the line." "It was the beginning of what the world now recognizes as a warship." "It was a significant turning point in military history." "[ Narrator] The battle kick-starts the worldwide race... to build the biggest, most powerful ﬂeet of iron ships." "But there's a secret weapon that makes modern warfare possible." "Big history connects the ironclads... to a four-billion-year-old rain of iron from the sky." "This molten mass is the newly formed planet Earth." "It's filled with metals like iron and nickel." "Metals so heavy, they sink down into the core, far out of reach." "But as the Earth cools... a solid crust forms a thick skin around the planet... that absorbs the impact of even more meteors." "Meteors filled with metals." "And when they started bombarding the early Earth... they brought those metals with them, deposited them." "And the reason we have those metals even around us today... is thanks to meteors and asteroids." "[ Narrator] Without these metals from space... humanity would be stuck in the Stone Age." "Instead, we figure out how to extract and master them... to build our civilization... bigger and stronger." "To make tools and machines... like the first modern warships." "80 if metals that hitch a ride on meteors can survive the journey through deep space... and our atmosphere... then a mystery remains." "What else do meteors bring us?" "The same barrage from space that delivered our metals... may also have delivered the most important one-two punch in history" "water." "Trillions of comets and asteroids carry enough to fill the oceans... creating an environment that can support what meteors bring next- life." "D.N.A. or even our earliest single-celled ancestors... may have arrived on Earth with a bang." "The idea is that life on Earth actually originated with microbes... that hitched a ride on a meteor... traveled through our solar system... landed on Earth and gave rise to everything we have today." "So they may have played a crucial role in the early history of life on Earth." "[ Narrator] But while meteors and comets may have brought life... they may also bring our ultimate destruction." "[ Narrator] Big history has shown... that meteors and comets are Earth's secret supplier of metal... water... and perhaps even life." "They carry so much energy that even a small impact leaves a big mark." "The meteor that explodes over Russia in 2013... is only 55 feet wide." "[ Explosion ]" "But it unleashes 30 times the energy... of the Hiroshima atomic bomb into the atmosphere." "80 when a meteor that's 600 times bigger makes contact... it's catastrophic." "Big History links back 65 million years." "[Growling 1" "This is Earth in the last days of the dinosaurs." "An asteroid six miles wide... is about to overturn the balance of power on the planet." "It smashes into the Gulf of Mexico somewhere near the Yucatén Peninsula." "[ Man ] The results were just catastrophic." "First, there's this massive impact... which is like all the world's nuclear weapons going off simultaneously." "Enormous earthquakes." "Enormous tsunamis." "Huge fires." "Then enormous amount of stuff going into the atmosphere which blocks sunlight." "[ Narrator] The Earth descends into darkness." "It's the equivalent of a nuclear winter that dooms the dinosaurs... and 75% of all animal species." "An impact of this magnitude only happens about every hundred million years." "And one species's catastrophe  [ Birds Chirping ]" " Is another's opportunity." "A good way to put it is that every extinction does reshufﬂe the deck." "You just take all of the playing cards, put them back, mix it up... and deal yourself a new hand." "[ Narrator] In the aftermath of the dinosaur die-off... our earliest ancestors emerge from the shadows." "If there had been no asteroid collision 65 million years ago... would the human species even exist?" "Probably not." "[ Man ] So it's interesting to consider that a gigantic impact... led to the demise of the dinosaurs... that ultimately allowed us to come into existence." "But, in the same way... another such impact could lead to our eventual destruction." "[ Narrator] Many large comets and asteroids are out there." "And some are heading toward Earth." "So far, we've identified more than 800 nearby... that measure more than a half a mile wide." "But even more dangerous are the objects we can't see." "[ Filippenko ] The orbits of asteroids can be tracked." "We can watch them circling the sun... and we can tell where they're going and where they will end up." "Comets are much more difficult to deal with." "We can't see these comets until they approach the sun for the first time." "So comets are actually more dangerous than asteroids." "[ Narrator] The meteors and comets that create... sculpt... and supply our planet... may ultimately destroy us in one final, colossal impact." "But what brings down mankind... could pave the way for something else." "[ Benjamin ] Ironically, it could be a meteor... that eventually extinguishes human life on this planet." "That's a sort of perspective, I think, that big history brings to human knowledge." "[ Narrator] But the story of meteors and comets is only the beginning." "There's a much bigger puzzle hidden in big history." "Each episode unlocks a clue." "Everyday things like the sun... water... and beef hold the key." "Watch them all and you'll see this grand mystery revealed." "The big history of time, of space." "The big history of us."