pale blue dot -carl sagan-第59部分

按键盘上方向键 ← 或 → 可快速上下翻页，按键盘上的 Enter 键可回到本书目录页，按键盘上方向键 ↑ 可回到本页顶部！
————未阅读完？加入书签已便下次继续阅读！


　mammals）。　Over　the　typical　lifetime　of　a　mammalian　species；　even　if　we　were　able　to　travel　close　to　the　speed　of　light　and　were　dedicated　to　nothing　else；　we　could　not；　I　think；　explore　even　a　representative　fraction　of　the　Milky　Way　Galaxy。　There's　just　too　much　of　it。　And　beyond　are　a　hundred　billion　galaxies　more。　Will　our　present　motivations　remain　unchanged　over　geological；　much　less　cosmological；　timescales—when　we　ourselves　have　been　transfigured？　In　such　remote　epochs；　we　may　discover　outlets　for　our　ambitions　far　grander　and　more　worthy　than　merely　populating　an　unlimited　number　of　worlds。

Perhaps；　some　scientists　have　imagined；　we　will　one　day　create　new　forms　of　life；　link　minds；　colonize　stars；　reconfigure　galaxies；　or　prevent；　in　a　nearby　volume　of　space；　the　expansion　of　the　Universe。　In　a　1993　article　in　the　journal　Nuclear　Physics；　the　physicist　Andrei　Linde—conceivably；　in　a　playful　mood—suggests　that　laboratory　experiments　（it　would　have　to　be　quite　a　laboratory）　to　create　separate；　closed…off；　expanding　universes　might　ultimately　be　possible。　〃However；〃　he　writes　to　me；　〃I　myself　do　not　know　whether　＇this　suggestion＇　is　simply　a　joke　or　something　else。〃　In　such　a　list　of　projects　for　the　far　future；　we　will　have　no　difficulty　in　recognizing　a　continuing　human　ambition　to　arrogate　powers　once　considered　godlike—or；　in　that　other　more　encouraging　metaphor；　to　plete　the　Creation。



FOR　MANY　PAGES　NOW；　we　have　left　the　realm　of　plausible　conjecture　for　the　heady　intoxication　of　nearly　unconstrained　speculation。　It　is　time　to　return　to　our　own　age。

My　grandfather；　born　before　radio　waves　were　even　a　laboratory　curiosity；　almost　lived　to　see　the　first　artificial　satellite　beeping　down　at　us　from　space。　There　are　people　who　were　born　before　there　was　such　a　thing　as　an　airplane；　and　who　in　old　age　saw　four　ships　launched　to　the　stars。　For　all　our　failings；　despite　our　limitations　and　fallibilities；　we　humans　are　capable　of　greatness。　This　is　true　of　our　science　and　some　areas　of　our　technology；　of　our　art；　music；　literature；　altruism；　and　passion；　and　even；　on　rare　occasion；　of　our　statecraft。　What　new　wonders　undreamt　of　in　our　time　will　we　have　wrought　in　another　generation？　And　another？　How　far　will　our　nomadic　species　have　wandered　by　the　end　of　the　next　century？　And　the　next　millennium？

Two　billion　years　ago　our　ancestors　were　microbes；　a　halfbillion　years　ago；　fish；　a　hundred　million　years　ago；　something　like　mice；　ten　million　years　ago；　arboreal　apes；　and　a　million　years　ago；　proto…humans　puzzling　out　the　taming　of　fire。　Our　evolutionary　lineage　is　marked　by　mastery　of　change。　In　our　time；　the　pace　is　quickening。

When　we　first　venture　to　a　near…Earth　asteroid；　we　will　have　entered　a　habitat　that　may　engage　our　species　forever。　The　first　voyage　of　men　and　women　to　Mars　is　the　key　step　in　transforming　us　into　a　multiplanet　species。　These　events　are　as　momentous　as　the　colonization　of　the　land　by　our　amphibian　ancestors　and　the　descent　from　the　trees　by　our　primate　ancestors。

Fish　with　rudimentary　lungs　and　fins　slightly　adapted　for　walking　must　have　died　in　great　numbers　before　establishing　a　permanent　foothold　on　the　land。　As　the　forests　slowly　receded；　our　upright　apelike　forebears　often　scurried　back　into　the　trees；　fleeing　the　predators　that　stalked　the　savannahs。　The　transitions　were　painful；　took　millions　of　years；　and　were　imperceptible　to　those　involved。　In　our　case　the　transition　occupies　only　a　few　generations；　and　with　only　a　handful　of　lives　lost。　The　pace　is　so　swift　that　we　are　still　barely　able　to　grasp　what　is　happening。

Once　the　first　children　are　born　off　Earth；　once　we　have　bases　and　homesteads　on　asteroids；　ets；　moons；　and　planets；　once　we're　living　off　the　land　and　bringing　up　new　generations　on　other　worlds；　something　will　have　changed　forever　in　human　history。　But　inhabiting　other　worlds　does　not　imply　abandoning　this　one；　any　more　than　the　evolution　of　amphibians　meant　the　end　of　fish。　For　a　very　long　time　only　a　small　fraction　of　us　will　be　out　there。

〃In　modern　Western　society；〃　writes　the　scholar　Charles　Lindholm；

the　erosion　of　tradition　and　the　collapse　of　accepted　religious　belief　leaves　us　without　a　telos　＇an　end　to　which　we　strive＇；　a　sanctified　notion　of　humanity's　potential。　Bereft　of　a　sacred　project；　we　have　only　a　demystified　image　of　a　frail　and　fallible　humanity　no　longer　capable　of　being　god…like。

I　believe　it　is　healthy—indeed；　essential—to　keep　our　frailty　and　fallibility　firmly　in　mind。　I　worry　about　people　who　aspire　to　be　〃god…like。〃　But　as　for　a　long…term　goal　and　a　sacred　project；　there　is　one　before　us。　On　it　the　very　survival　of　our　species　depends。　If　we　have　been　locked　and　bolted　into　a　prison　of　the　self；　here　is　an　escape　hatch—something　worthy；　something　vastly　larger　than　ourselves；　a　crucial　act　on　behalf　of　humanity。　Peopling　other　worlds　unifies　nations　and　ethnic　groups；　binds　the　generations；　and　requires　us　to　be　both　smart　and　wise。　It　liberates　our　nature　and；　in　part；　returns　us　to　our　beginnings。　Even　now；　this　new　telos　is　within　our　grasp。

The　pioneering　psychologist　William　James　called　religion　a　〃feeling　of　being　at　home　in　the　Universe。〃　Our　tendency　has　been；　as　I　described　in　the　early　chapters　of　this　book；　to　pretend　that　the　Universe　is　how　we　wish　our　home　would　be；　rather　than　to　revise　our　notion　of　what's　homey　so　it　embraces　the　Universe。　If；　in　considering　James'　definition；　we　mean　the　real　Universe；　then　we　have　no　true　religion　yet。　That　is　for　another　time；　when　the　sting　of　the　Great　Demotions　is　well　behind　us；　when　we　are　acclimatized　to　other　worlds　and　they　to　us；　when　we　are　spreading　outward　to　the　stars。

The　Cosmos　extends；　for　all　practical　purposes；　forever。　After　a　brief　sedentary　hiatus；　we　are　resuming　our　ancient　nomadic　way　of　life。　Our　remote　descendants；　safely　arrayed　on　many　worlds　through　the　Solar　System　and　beyond；　will　be　unified　by　their　mon　heritage；　by　their　regard　for　their　home　planet；　and　by　the　knowledge　that；　whatever　other　life　may　be；　the　only　humans　in　all　the　Universe　e　from　Earth。

They　will　gaze　up　and　strain　to　find　the　blue　dot　in　their　skies。　They　will　love　it　no　less　for　its　obscurity　and　fragility。　They　will　marvel　at　how　vulnerable　the　repository　of　all　our　potential　once　was；　how　perilous　our　infancy；　how　humble　our　beginnings；　how　many　rivers　we　had　to　cross　before　we　found　our　way。




ABOUT　THE　AUTHOR

　
CARL　SAGAN　was　the　David　Duncan　Professor　of　Astronomy　and　Space　Sciences　and　Director　of　the　Laboratory　for　Planetary　Studies　at　Cornell　University。　He　played　a　leading　role　in　the　American　space　program　since　its　inception。　He　was　a　consultant　and　advisor　to　NASA　since　the　1950s；　briefed　the　Apollo　astronauts　before　their　flights　to　the　Moon；　and　was　an　experimenter　on　the　Mariner；　Viking；　Voyager；　and　Galileo　expeditions　to　the　planets。　He　helped　solve　the　mysteries　of　the　high　temperature　of　Venus　（answer：　massive　greenhouse　effect）；　the　seasonal　changes　on　Mars　（answer：　windblown　dust）；　and　the　reddish　haze　of　Titan　（answer：　plex　organic　molecules）。

For　his　work；　Dr。　Sagan　received　the　NASA　medals　for　Exceptional　Scientific　Achievement　and　（twice）　for　Distinguished　Public　Service；　as　well　as　the　NASA　Apollo　Achievement　Award。　Asteroid　2709　Sagan　is　named　after　him。　He　was　also　awarded　the　John　F。　Kennedy　Astronautics　Award　of　the　American　Astronautical　Society；　the　Explorers　Club　75th　Anniversary　Award；　the　Konstantin　Tsiolkovsky　Medal　of　the　Soviet　Cosmonauts　Federation；　and　the　Masursky　Award　of　the　American　Astronomical　Society　（〃for　his　extraordinary　contributions　to　the　development　of　planetary　science　。。。。　As　a　scientist　trained　in　both　astronomy　and　biology；　Dr。　Sagan　has　made　seminal　contributions　to　the　study　of　planetary　atmospheres；　planetary　surfaces；　the　history　of　the　Earth；　and　exobiology。　Many　of　the　most　productive　planetary　scientists　working　today　are　his　present　and　former　students　and　associates〃）。



ACKNOWLEDGMENTS



Most　of　the　material　in　this　book　is　new。　A　number　of　chapters　have　evolved　from　articles　first　published　in　Parade　magazine；　a　supplement　to　the　Sunday　editions　of　American　newspapers　which；　with　an　estimated　80　million　readers；　may　be　the　most　widely　read　magazine　in　the　world。　I　am　greatly　indebted　to　Walter　Anderson；　the　editor…in…chief；　and　David　Currier；　the　executive　editor；　for　their　encouragement　and　editorial　wisdom；　and　to　the　readers　of　Parade；　whose　letters　have　helped　me　understand　where　I　have　been　clear；　and　where　obscure；　and　how　my　arguments　are　received。　Portions　of　other　chapters　have　emerged　from　articles　published　in　Issues　in　Science　and　Technology；　Discover；　The　Planetary　Report；　Scientific　American；　and　Popular　Mechanics。

Aspects　of　this　book　have　been　discussed　with　a　large　number　of　friends　and　colleagues；　whose　ments　have　greatly　improved　it。　Although　there　are　too　many　to　list　by　name；　I　would　like　to　express　my　real　gratitude　to　all　of　them。　I　want　especially；　though；　to　thank　Norman　Augustine；　Roger　Bonnet；　Freeman　Dyson；　Louis　Friedman；　Everett　Gibson；　Daniel　Goldin；　J。　Richard　Gott　III；　Andrei　Linde；　Jon　Lomberg；　David　Morrison；　Roald　Sagdeev；　Steven　Soter；　Kip　Throne；　and　Frederick　Turner　for　their　ments　on　all　or　part　of　the　manuscript；　Seth　Kaufmann；　Peter　Thomas；　and　Joshua　Grinspoon　for　their　help　with　tables　and　graphs；　and　a　brilliant　array　of　astronomical　artists；　acknowledged　at　each　illustration；　who　have　permitted　me　to　showcase　some　of　their　work。　Through　the　generosity　of　Kathy　Hoyt；　Al　McEwen；　and　Larry　Soderblom；　I've　been　able　to　display　some　of　the　exceptional　photomosiacs；　airbrush　maps；　and　other　reductions　of　NASA　images　acplished　at　the　Branch　of　Astrogeology；　U。S。　Geological　Survey。

I　am　indebted　to　Andrea　Barnett；　Laurel　Parker；　Jennifer　Bland；　Loren　Mooney；　Karenn　Gobrecht；　Deborah　Pearlstein；　and　the　late　Eleanor　York　for　their　able　technical　assistance；　and　to　Harry　Evans；　Walter　Weintz；　Ann　Godoff；　Kathy　Rosenbloom；　Andy　Carpenter；　Martha　Schwartz；　and　Alan　MacRobert　on　the　production　end。　Beth　Tondreau　is　responsible　for　much　of　the　design　elegance　on　these　pages。

On　matters　of　space　policy；　I　have　benefited　from　disc