"NEIL DEGRASSE TYSON:" "Mustwedie?" "Aretherebeingsinthecosmos wholiveforever afloatonan endlessjourney downtheriveroftime ?" "¶ ¶" "¶ ¶" "¶ ¶" "DEGRASSE TYSON:" "Our ancestors markedthepassageoftime  bytheMoonand stars." "But it was the people who once lived here, around 5,000 years ago, who first starting chopping up time into smaller bite-sized portions of hours and minutes." "They call this place Uruk." "We call it Iraq." "It's a part of Mesopotamia, the land between the Tigris and the Euphrates rivers." "The city was invented here." "And one of humanity's greatest victories was won in the ceaseless battle against time." "It was here that we learned how to write." "Death could no longer silence us." "And writing gave us the power to reach across the millennia and speak inside the heads of the living." "Noonehaseverspoken acrossa longerstretch oftime'sriver thanthisAkkadianprincess, daughterofthefirstemperor inhistory, andpriestessof theMoon-- Enheduanna." "Fornotonly didshewritepoetry, butEnheduannadidsomething noonebeforeher  hadeverdone-- shesignedhername toherwork." "She'sthefirstperson forwhomwe cansay  weknowwhoshe was , andwhatshedreamed." "Shedreamtof stepping throughtheGateofWonder." "Here'sa thought Enheduannasent acrossmorethan4,000years toyou." "It'sfromherworkentitled" "Lady of the Largest Heart." "(Enheduanna speaking Sumerian)" "ENHEDUANNA (translated):" "Innana,theplanetVenus, goddessoflove, willhaveagreatdestiny throughouttheentireuniverse." "(echoing): ...throughout theentireuniverse." "And Uruk is also the place where the epic tale of "The Hero's Journey" was first written down." "Before Batman, Luke Skywalker," "Odysseus-- before them all-- there was a man named Gilgamesh wholefthomeona quest tovanquishtime." "Gilgameshwassearching forimmortality." "Helookedeverywhere, gainedcompletewisdom, uncoveredwhatwashidden." "Hebroughtbackatale oftimes  beforetheGreatFlood." "(creature growling)" "HebuilttheWallofUruk,  whichnofutureking willevermatch." "Readthestory ofthatmanGilgamesh, aherobornofUruk , whowentthroughall kinds ofsufferings." "Whocrossedtheocean, thebroadseas, asfaras thesunrise;" "whoinspected theedgesof theworld, searchingforeternallife." "Onhistravels," "Gilgameshencountered awisemannamedUtnapishtim, whotoldhimthe storyofa floodthatdestroyedthe world, andhowoneofthegods instructedUtnapishtim tobuildan arktorescue hisfamilyandthe animals." "(thunder crashing)" "(dove cooing)" "Theearliestsurvivingaccount ofthefloodlegend was written down in Mesopotamia, a thousand years before it was retold as the story of Noah in the Old Testament." "So, you could say Gilgamesh fulfilled his quest for immortality." "We still read the Epic of Gilgamesh, and with every reader, he lives again." "And all those heroes and superheroes who have come since follow in the footsteps of the first hero's journey-- another kind of immortality;" "a story sent from one civilization to another across thousands of years." "But life itself sends its own stories across billions of years." "It's a message that every one of us carries inside, inscribed in all the cells of our bodies, in a language that all life on Earth can read." "The genetic code is written in an alphabet consisting of only four letters." "Each letter is a molecule made of atoms;" "each word is three letters long." "Every living thing is a masterpiece, written by nature and edited by evolution;" "the instructions for running and reproducing the intricate machinery of life." "The essential message of life has been copied and recopied for more than 3 billion years." "But where did that message come from?" "Nobody knows." "Perhaps it began in a shallow, sunlit pool, just like this." "Somehow, carbon-rich molecules began using energy to make crude copies of themselves." "Some varieties were better at making copies, and left more offspring." "The competing molecules became more elaborate." "Evolution and life itself was underway." "Orlifecould'vestarted inthesearingheat ofa volcanicvent onthedeepsea floor." "Orisit possible thatlifecametoEarth asa hitchhiker?" "Letmetellyou astory abouta traveler fromanotherworld." "Thepeaceof theEgyptian villageofNakhla, nearAlexandria, wasabruptlyshattered ona Junemorningin1911 ." "Writteninthismeteoritewas amessagefromanotherplanet." "But70yearswouldpass  beforeanyonecouldreadit." "In1976," "NASAlandedtwoViking spacecraftonMars." "CarlSagantookusthere onouroriginaljourney throughthecosmos." "CARL SAGAN:" "Wefoundthatthe Martianair waslessthanone percent asdenseas ours, andmademostly ofcarbondioxide." "Thereweresmalleramounts ofnitrogen, argon,watervaporand oxygen." "DEGRASSE TYSON:" "Afewyearslater, whenscientiststhought toanalyzethegasses trappedinside theNakhlameteorite, andothermembersofitsclass , theyfound astrikingsimilarity-- thevastmajorityofmeteorites arefragmentsof asteroids." "Butthekind thathitNakhla,onEarth, couldonlyhavecome fromoneplace..." "Mars." "WelcometoMars." "Over a billion years ago, a volcano erupted here and its lava cooled into solid rock." "Hundreds of millions of years later, this area was flooded with water." "And long after that flood, an asteroid the size of the Rock of Gibraltar crashed into the Martian surface, blasting out a huge crater." "Much of the debris was ejected back out into space, where it orbited the Sun until a gravitational tug from its home planet, Mars, diverted one of the boulders into a collision course with Earth." "Its arrival shook up the little village of Nakhla." "Meteorites of the type that hit Nakhla are the vehicles of a natural interplanetary transit system that sends rocks between the planets." "Sucha meteoritecansafely sheltermicroscopiccargo-- theseedsof life-- an interplanetary ark." "Most rocks are porous, full of tiny nooks and crannies, where life can stow away." "Weknow thatsomemicrobescan survive thehostileenvironment ofspace." "Taketheseguys,for instance." "Thesemicrobesspentayear  anda halfriding ontheoutsideofthe InternationalSpaceStation, exposedtotheextreme temperatures,vacuum, andradiationof space." "Andsomeof them werestillaliveand kicking whentheywerebroughtback  toEarth." "Evenmoreastonishing arethesecreatures, awakenedfromadeathlikesleep ofeightmillionyears." "Theywerefrozen intheAntarcticice  millionsofyearsbefore ourspeciesevenexisted." "And they're still alive." "Iflifecanwithstand thehardshipsof space and endure for millennia, then it could ride the natural interplanetary transit system from world to world." "It's a good bet that our microbial ancestors spent some time in space." "Why do we think so?" "The Earth is four-and-a-half- billion-years old." "Forthefirsthalf ofitslifetime, largeasteroidswerebombarding theplanet everyfewmillionyears." "Themostviolentimpacts vaporizedtheoceans andevenmelted thesurfacerock." "Eachsuchcollisionwouldhave  completelysterilized theplanet forthousandsof years." "Butweknowfromfossils intherocks thatbacteriawereevolving onEarth duringthisformativeperiod." "Sohowcouldlifehave survived sucha lethalseriesofblows?" "Wheneverone ofthosebigasteroids hit the Earth, the explosion would blast out a crater, launching millions of boulders into space." "Many of those rocks carried living bacteria inside." "Some of the bugs would have survived in space, while all those left behind on Earth would have been fried." "A few thousand years after each impact, the Earth would have cooled down enough for water to condense into oceans." "The planet would again be habitable." "Meanwhile, most of the rocks launched into space would have been orbiting the Sun." "Someofthemwouldencounter theEarthagain, reentertheatmosphere asmeteorites, anddelivertheirprecious cargooflife tore-seedtheplanet likeNoah'sark." "Whatthismeansisthat life  doesn'thave tostartoveragainfrom  scratchaftereachcatastrophe." "Itcanpickup whereitleftoff ." "When the solar system was young," "Venus was probably more like Earth, with oceans and maybe even life." "Venus, Earth, and Mars were all exchanging rocks with each other, due to asteroid impacts." "Does life on Earth carry any traces of interplanetary voyages made in the distant past?" "Why is it that some microbes can survive the intense radiation and vacuum of space?" "These conditions don't naturally exist on Earth." "Maybe those bugs are telling us that their ancestors survived those same conditions in space, a few billion years ago." "So we know that microbes can stow away in rocks and survive the voyage from planet to planet." "But what about trip from star to star-- an interstellar odyssey?" "The dandelion." "Around 30 million years ago, it evolved another way to send its own message of life through space and time." "Eachseedling isa littleparatrooper, floatingonthewind, riskingeverything fora safeplacetoland ." "Updraftscancarrythem higherintotheair ." "Adandelioncantraveldozens, possiblyhundreds ofkilometers, evencrossingover mountainranges." "Evolutionhasshapeditinto  anexquisiteflyingmachine." "The seed is another kind or ark, ensuring the survival of its species by riding the currents of the atmosphere to safe harbors." "Each seed in its DNA carries a story, the character and destiny of the next dandelion-- life propagates by retelling its story." "Isitpossiblethatlife  couldsurvivethejourney fromstarto star?" "The stars are about a million times farther apart from each other than are the planets." "Space is so vast that it would take billions of years for a rock ejected from the Earth to collide with a planet circling another star." "Any stowaway microbes would never survive the cosmic radiation for that long." "But there's a plausible scenario for how life could spread from one solar system to another." "Thestarsof theMilkyWay aredrawnby gravity intheirownenormousorbits arounditscenter." "OurSun,forexample, takessome225millionyears tocompleteasingleorbit." "Duringeachrevolutionaround thegalaxy, oursolarsystemwill passthroughtwoorthree giganticinterstellarclouds, eachofthem manylightyearsacross." "Galaxiesare world-makingmachines." "OurMilkyWayhas morethan  100ofthesevastclouds, placeswheregasand dust condense toformnewstarsandplanets." "In its travels through the Milky Way, ourSunis accompaniednot only byitsplanets, butalsoby  atrilliondistantcomets." "Whenoursolarsystempasses throughaninterstellarcloud, thegravityof  themassivecloud stirsuptheoutermostcomets." "Somecometswillbehurledout intothespace betweenthestars." "Otherswillplungeinward fallingtowardstheSun ." "(explosion thundering)" "Andsomeof themmay collide withtheplanets." "Thehigh-speedimpact ofa cometwitharockyplanet willlaunchboulders likerocketsintospace." "Ifthatplanetshould happentobe inhabited, manyofthoserocks willcarrypassengers-- livingmicrobes." "Afterthousandsof years, fragmentsoftherocks ejectedfromEarth canfallas meteorsintothe atmospheresofnewbornplanets intheinterstellarcloud." "Ifthestowawaymicrobes shouldhappento come incontactwithliquidwater, theycanreviveand reproduce." "Thismaybe  howlifecomesbarreling intothebarrenplaces." "The sun emerges from the cloud, having scattered the seeds of life among the newborn worlds of other stars." "Those new worlds, now touched by life, will then leave their birth cloud and go their separate ways." "Eventually, their stars will carry them through other interstellar clouds, where they may seed still more new worlds." "Imaginethisprocess repeatedfromworldtoworld, eachonebringinglife toothers." "Life would then propagate, like a slow chain reaction, through the entire galaxy." "Thiscouldbe  howlifecametoEarth." "Wedonotknowforsure." "Are there any beings out there like us?" "Do they ask the same questions?" "Do they share our fears?" "(bell tolls)" "Do they have heroes and adventures?" "(bell tolling)" "If they do exist, where are they?" "How might they make their presence known?" "How did we first announce our presence to the galaxy?" "It was 1946, the year after the Second World War ended." "NEWSREEL ANNOUNCER:" "Thevividimaginations ofH.G.Wellsand BuckRogers nevercookedup amore fantasticexperience thantheArmyengineers attheirlaboratory inBelmar,NewJersey." "Itopensup  unlimitedpossibilities forinterstellarexperiment." "DEGRASSE TYSON:" "Americanengineers bounceda beam ofradiowavesoff the Moon, andwereable todetectitsecho." "(electronic thrumming)" "(electronic warbling and static)" "Theycalledthisexperiment ProjectDiana." "Itwasthefirst interstellarmessage eversentby ourspecies... (bell tolling) ...aneerie,tollingbell." "If one allows the imagination free reign, many future possibilities appear." "Spaceships, carrying passengers at thousands of miles per hour, can be controlled and communication established with their passengers, for we now know that the Earth's atmosphere can be penetrated." "DEGRASSE TYSON:" "Traveling at thespeedof light, ittakesjustoveronesecond fora radiowave toreachthelunarsurface." "Buttheexpandingwavefront ismuchbiggerthantheMoon." "Mostofthewave passesrightby it , butthecentralpart getsbouncedback." "Aftera round-triptraveltime oftwoandahalf seconds, ithitsourplanet." "ProjectDianatransmitted aseriesof powerful radiowaves-- oneeveryfourseconds-- to" ping"theMoon." "(bell tolling)" "ThepartsthatmissedtheMoon aretravelingstill." "(garbled voices, static)" "Itwasjustthe beginning." "AfterWorldWarII,  televisionstationscroppedup allovertheUnitedStates, andotherpartsoftheworld ." "(various overlapping voices and static)" "TheProjectDianamessage andtheFM radio,television andradarsignals ofthe20thcentury allmoveoutward atthespeedoflight." "Thesetransmissionsmakeup avastsphereofradiowaves , expandingawayfromthe Earth inalldirections." "Youcouldsaythatourworld  isradiatingstories." "Ourancestorsetched thestoryof Gilgamesh intoclaytablets, sendingthatepictale intothefuture." "We'veencodedourstories inradiowaves andbeamedthemintospace." "Theycoveronelight-year ofdistance-- that'ssixtrillionmiles-- foreveryyearoftime  sincetheyweresent." "We'vebeensending ourstoriesintospace forover70 years." "Theleadingedge ofthesesignals hasalreadywashedover thousandsofplanets ofotherstars." "Ifanyof theseworldsarehome toa civilization withradiotelescopes, theycouldalreadyknow thatwe'rehere." "Whatifotherworlds aresending theirstoriesintospace?" "Since1960, we'vebeenlistening forextraterrestrial radiosignals withouthearingso much asa tollingbell." "Butoursearch hasbeensporadic andlimitedto  certainpartsof thesky ." "Forallwe know, wemayhavejustmissed analiensignal, lookinginthewrongplace atthewrongtime." "We'veonlylistenedto aminisculefraction ofthestarsinourgalaxy." "Andtheremaybe anotherproblem:" "weare,to someextent, prisonersofourown  momentintime andthelimits ofourtechnology." "Radioandtelevision broadcasting maybeonly abriefpassingphase inourtechnological development." "Whenweimagine aliencivilizations broadcastingsignals withradiotelescopes, areweanydifferent fromearliergenerations whoimaginedriding cannonshellsto theMoon?" "Civilizationsevensliy moreadvancedthanours mayhavealreadymovedon tosomeothermode ofcommunication, onethatwe have yettodiscover orevenimagine." "Theirmessagescouldbe swirlingaroundus , atthisverymoment, butwelackthe means toperceivethem, justasallofourancestors, uptoalittlemore  thana centuryago, wouldhavebeenobliviousto themosturgentradiosignal" "fromanotherworld." "Butthere'sanother, moretroublingpossibility-- civilizations, likeotherlivingthings, mayonlylivesolong  beforeperishing duetonaturalcauses, orviolence, orself-inflictedwounds." "Whetherornot weevermakecontact withintelligentalienlife maydependon  acriticalquestion:" "Whatisthelifeexpectancy ofa civilization?" "DEGRASSE TYSON:" "BythetimeofEnheduanna, thefirstperson toevergetawritingcredit, civilizationwasalready morethan1,000yearsold." "But today, her glorious city is a barren wasteland." "What went wrong?" "One problem was the almost ceaseless warfare between the cities of Mesopotamia, which continually destroyed their achievements." "They glorified military conquest and ultimately became its victims." "Anothercauseof decline wasthattheir technicalknow-how overrantheir understandingofnature." "Theingeniousirrigationsystem thatwasthebasis forthegreatcivilizations ofMesopotamia hadanunintendedconsequence-- thewaterchanneledinto theirfarmlandseveryyear evaporatedandleft itssaltbehind." "Overgenerations, thesaltaccumulated andbeganto killthe crops." "Andthen,about2,200BC, notlongafter thetimeof Enheduanna, disasterstruck:" "adroughtof truly epicproportions, lastingformanydecades." "Therainsstopped, cropswithered, andtherewasfamine andanarchy." "Barbariansinvaded." "Thestreetsof manycities werelitteredwithdead." "Therecouldbe only oneexplanation:" "Enlil,thesupremegod , wasangrybecause oneofhistemples hadbeendestroyed." "Thepeopleof Mesopotamia couldnotknow thatthesamedrought wascrushing thedawningcivilizations ofEgypt," "Greece,India," "PakistanandChina." "AllthegodsoftheEarth  musthavebeenreallyangry aboutsomething." "Foralltheirbrilliance, thepeopleof  thosecivilizations hadnoinkling theywereexperiencing" "(bird screeches) abruptclimatechange." "3,000yearslater,the climate wouldchangeabruptlyfor  anothergloriouscivilization, thisonein CentralAmerica." "Atitspeak, theMayancivilization perished, wipedoutby aseries ofseveredroughts overthecourseofa century." "Westillcarrywithinus theechoesof these extinctcivilizations inourlanguagesand our myths." "Today,wehaveasingle globalcivilization." "Howlongwillitlive ?" "Thereareso manyways fora civilizationto die." "Let's start with the ones that we probably wouldn't be able to do much about." "Thatsupernova is1,000light-yearsaway." "Ifitweremuchcloser,say... lessthan30 light-years fromEarth, itscosmicradiation wouldshred theatmosphere's protectiveozonelayer and destroy our civilization." "Lucky for us, none of the stars close enough to harm us are likely to go supernova any time in the next few hundred million years." "Everymillionyearsorso, asupervolcanoerupts somewhereonEarth." "Thelasttimeithappened was74,000yearsago , ontheislandofSumatra, inwhatis nowIndonesia." "Itspewed hundredsoftimesmore rock,ashandtoxicgas thananysinglevolcano inrecordedhistory." "Themoltenrockthaterupted fromEarth'scrust leftthiscaldera," "100kilometerslong, nowfilledwithalake ." "TheTobavolcanosent morethan600cubicmiles ofpulverizedrock soaringskyward." "Thewestwardwindcarriedthe volcanicashoverIndia, whereitfellout  ina smotheringblanket overthesubcontinent." "Theeruptionloaded theupperatmosphere withsulfurgases." "Theresultwasaglobalhaze thatblockedmost ofthesunlight fromreachingthesurface foratleastfiveyears." "Itwaslikeone  five-year-longcloudyday." "Thisso-called "volcanicwinter"" "resembleda " nuclearwinter," butwithouttheradiation." "Temperatures fell everywhere." "Plants and animals froze even in the tropics, dying in enormous numbers." "But life is hardy." "Only a few species were driven to extinction." "One of our ancestors in central India sharpened this stone blade in the years before the Toba eruption." "And this blade was one of dozens that were found in the soil layer above the volcanic fallout." "This tells us that some toolmakers, even in the area directly affected by the volcano, managed to survive the cataclysm." "But the global human population must have plummeted before rebounding." "If an eruption like this were to happen tomorrow, our civilization would be brought to its knees, although the human species would survive." "I can imagine that our technology of a few hundred years from now would allow us to siphon off the energy of a threatening supervolcano before it explodes." "We could then use that energy for our own purposes." "About once every million years, a small asteroid collideswiththeEarth, causinga similaramount ofdevastation." "Withourcurrentscience andtechnology, wealreadyknowhow toprevent anasteroidimpact." "Wewouldseeitcoming yearsinadvance andcouldsend aspacecraftthere todeflectit into aharmlessorbit." "With the technology of a thousand years from now, we might even be able to mitigate the deadly effects of a nearby supernova on Earth's atmosphere." "But what happens when the danger to a civilization is invisible?" "When no one can see it coming?" "DEGRASSE TYSON:" "BeginningwithColumbus, theEuropeaninvaders oftheAmericas had a secret weapon that even they knew nothing about." "Theywerecarrying bacteriaandviruses fordeadlydiseases, suchassmallpox, thattheoriginalAmericans hadneverbeenexposedto." "TheEuropeansliketobelieve thatitwastheirvalor andsuperiorweapons andculture thatwonthemthe New World." "Therealconquistadorswere thearmiesof thepathogens thatracedon ahead toinfectandkillnine out oftenof allthe Indians ofNorth,Central andSouthAmerica." "Thegreatcivilizations oftheNewWorld crumbledundertheonslaught ofinvadingmicrobes." "Withouthisinvisiblearmy," "Cortezandthosewho followed mightnever havestoodachance." "But what about civilizations that self-destruct?" "Oureconomicsystemswere formedwhentheplanet anditsair,rivers, oceans,lands, allseemedinfinite." "Theyevolvedlongbefore wefirstsawthe Earth asthetinyorganism thatitactuallyis." "They'reallalike inonerespect:" "they'reprofit-driven, andtherefore, focusedonshort-termgain." "Theprevailing economicsystems, nomatterwhat theirideologies, havenobuilt-inmechanisms forprotectingourdescendants ofeven100yearsfrom now,  letalone,100,000." "In one respect, we're ahead of the people of Ancient Mesopotamia." "Unlike them, we understand what's happening to our world." "For example, we're pumping greenhouse gasses into our atmosphere at a rate not seen on Earth for a million years." "And the scientific consensus that we're destabilizing our climate." "Yet our civilization seems to be in the grip of denial;" "a kind of paralysis." "There's a disconnect between what we know and what we do." "Being able to adapt our behavior to challenges is as good a definition of intelligence as any I know." "Ifourgreaterintelligence isthehallmarkofourspecies, thenweshoulduse it,  asallotherbeingsusetheir  distinctiveadvantages-- tohelpensure thattheiroffspringprosper, andtheirheredity ispassedon ," "andthatthefabricofnature thatsustainsus is protected." "Humanintelligence isimperfect,surely, andnewlyarisen." "Theeasewithwhichitcanbe  sweet-talked,overwhelmed, orsubvertedby other hard-wiredtendencies, sometimesthemselvesdisguised asthelightofreason, isworrisome." "Butifourintelligence istheonlyedge, wemustlearntouseitbetter ." "Tosharpenit ." "Tounderstanditslimitations anddeficiencies." "Touseit as catsuse stealth beforepouncing." "Aswalkingsticks usecamouflage." "Tomakeit thetool ofoursurvival." "Ifwedo this,wecansolve  almostanyproblem wearelikelytoconfront inthenext100,000years." "Andnowwe 'vearrived attheplace whereourancientdreams ofimmortality and modern astrophysics converge." "Giant elliptical galaxies are something like..." "Florida, where the oldest stars in the universe may be found." "Thisisared dwarfstar , smallerandfainter thanourSun." "Reddwarfsarebyfarthemost plentifulstarsin thecosmos." "UnliketheSun,whichis halfwaythrough its10-billion-yearlifetime, reddwarfswillcontinue toprovidelightand warmth totheirplanets fortrillionsof years." "That'shundredsof timeslonger thanthepresentage  oftheuniverse." "Whatwould intelligentbeingsdo  iftheyhadaneternity todeveloptheirunderstanding oftheuniverse?" "Perhapstheywouldlearn howtoopenshortcuts inthefabricofspacetime, totravelbetweengalaxies fasterthanthespeedoflight ." "Maybetheywouldcreate wholenewuniverses asartistic orscientificexperiments." "Of course no one, or at least nobody on Earth, knows what the immortals might do." "(film projector whirring)" "If one allows the imagination free reign." "But what about us?" "What is our own future?" "What would the Cosmic Calendar of the next 14 billion years look like?" "If the original Cosmic Calendar includes all of time from the birth of the universe until this very moment... what would the Cosmic Calendar look like for the next 14 billion years?" "Just as with the Cosmic Calendar of the past, every month on the future calendar equals about a billion years;" "every day, some 40 million." "Science makes it possible for us to foretell certain astronomical events in the unimaginably distant future-- the death of the Sun, for example." "Insomefivebillionyears, ourstarwillhave exhausteditshydrogen-- thenuclearfuel thatpowersit-- becominga redgiant." "Iknowthatsoundsdepressing, butifwe applyour  intelligence,ourdescendants ofthatdistantfuture willhavelongdeparted fromthelostworlds oftheSun." "Whoknows?" "Human events entail too many variables, too many uncertainties, to make scientific statements about our future." "But we can still dream." "The next golden age of human achievement begins here and now" "NewYear'sDay ofthenextcosmicyear ." "Inthefirsttenthofasecond , wetakethevision ofthepalebluedottoheart,  andlearnhowtosharethis tinyworldwitheachother." "The last internal combustion engine is placed in a museum, as the effects of climate change reverse and diminish." "Afifthof asecond intothisfuture peoplewillstopdying fromtheeffectsofpoverty." "Theplanetis now acompletelyself-sustaining, intercommunicatingorganism." "Ahalf-secondfromnow , the polar ice caps are restored to the way they were in the 19th century, andtheforecast ismildandpleasant forthenextcosmic minuteandahalf" "40,000years." "Bythetime wearereadytosettle eventhenearest otherplanetarysystems, wewillhavechanged." "Thesimplepassage ofsomanygenerations willhavechangedus." "Necessitywillhavechangedus." "Wearean adaptablespecies." "Itwillnotbewe whoreachAlphaCentauri andtheother nearbystarsystems onourinterstellararks." "Itwillbe aspecies verylikeus , butwithmoreofourstrengths andfewerof ourweaknesses;" "moreconfident,far-seeing, capableandwise." "Forallourfailings, despiteourflaws andlimitations, wehumansarecapable ofgreatness." "Whatnewwonders, undreamtofin ourtime, willwehaveaccomplished inanothergeneration... andanother?" "Howfarwill ournomadicspecies havewandered bytheendofthenextcentury, andthenextmillennium?" "Ourremotedescendants, safelyarrayedon manyworlds throughoutthesolarsystem andbeyond, willbeunified bytheircommonheritage, bytheirregard fortheirhomeplanet, andbytheirknowledgethat , whateverotherlifemay be," "theonlyhumans inalltheuniverse camefromEarth." "Theywillgazeup andstrainto find thebluedotintheirskies ." "Theywillmarvel athowvulnerable therepositoryof all ourpotentialoncewas , howperilousourinfancy, howhumbleourbeginnings, howmanyrivers wehadto cross beforewefoundour way ." "Captioned by MediaAccessGroupatWGBH  access.wgbh.org"