¡¶pale blue dot -carl sagan¡·

ÏÂÔر¾Êé

Ìí¼ÓÊéÇ©

pale blue dot -carl sagan- µÚ63½Ú


°´¼üÅÌÉÏ·½Ïò¼ü ¡û »ò ¡ú ¿É¿ìËÙÉÏÏ·­Ò³£¬°´¼üÅÌÉ쵀 Enter ¼ü¿É»Øµ½±¾ÊéĿ¼ҳ£¬°´¼üÅÌÉÏ·½Ïò¼ü ¡ü ¿É»Øµ½±¾Ò³¶¥²¿£¡
rface¡¡temperatures¡¡close¡¡enough¡¡to¡¡the¡¡freezing¡¡point¡¡of¡¡water¡¡for¡¡the¡¡second¡¡phase¡¡of¡¡Martian¡¡terraforming¡¡to¡¡begin¡ªtemperatures¡¡rising¡¡due¡¡to¡¡the¡¡pressure¡¡of¡¡substantial¡¡water¡¡vapor¡¡in¡¡the¡¡air£»¡¡widespread¡¡production¡¡of¡¡O2¡¡by¡¡genetically¡¡engineered¡¡plants£»¡¡and¡¡fine¡­tuning¡¡the¡¡surface¡¡environment¡£¡¡Microbes¡¡and¡¡larger¡¡plants¡¡and¡¡animals¡¡could¡¡be¡¡established¡¡on¡¡Mars¡¡before¡¡the¡¡overall¡¡environment¡¡was¡¡suitable¡¡for¡¡unprotected¡¡human¡¡settlers¡£

Terraforming¡¡Mars¡¡is¡¡plainly¡¡much¡¡easier¡¡than¡¡terraforming¡¡Venus¡£¡¡But¡¡it¡¡is¡¡still¡¡very¡¡expensive¡¡by¡¡present¡¡standards£»¡¡and¡¡environmentally¡¡destructive¡£¡¡If¡¡there¡¡were¡¡sufficient¡¡justification£»¡¡though£»¡¡perhaps¡¡the¡¡terraforming¡¡of¡¡Mars¡¡could¡¡be¡¡under¡¡way¡¡by¡¡the¡¡twenty¡­second¡¡century¡£

THE¡¡MOONS¡¡OF¡¡JUPITER¡¡AND¡¡SATURN£º¡¡Terraforming¡¡the¡¡satellites¡¡of¡¡the¡¡Jovian¡¡planets¡¡presents¡¡varying¡¡degrees¡¡of¡¡difficulty¡£¡¡Perhaps¡¡the¡¡easiest¡¡to¡¡contemplate¡¡is¡¡Titan¡£¡¡It¡¡already¡¡has¡¡an¡¡atmosphere£»¡¡made¡¡mainly¡¡of¡¡N2¡¡like¡¡the¡¡Earth's£»¡¡and¡¡is¡¡much¡¡closer¡¡to¡¡terrestrial¡¡atmospheric¡¡pressures¡¡than¡¡either¡¡Venus¡¡or¡¡Mars¡£¡¡Moreover£»¡¡important¡¡greenhouse¡¡gases£»¡¡such¡¡as¡¡NH3¡¡and¡¡H2O£»¡¡are¡¡almost¡¡certainly¡¡frozen¡¡out¡¡on¡¡its¡¡surface¡£¡¡Manufacture¡¡of¡¡initial¡¡greenhouse¡¡gases¡¡that¡¡do¡¡not¡¡freeze¡¡out¡¡at¡¡present¡¡Titan¡¡temperatures¡¡plus¡¡direct¡¡warming¡¡of¡¡the¡¡surface¡¡by¡¡nuclear¡¡fusion¡¡could£»¡¡it¡¡seems£»¡¡be¡¡the¡¡key¡¡early¡¡steps¡¡to¡¡one¡¡day¡¡terraform¡¡Titan¡£



IF¡¡THERE¡¡WERE¡¡A¡¡PELLING¡¡REASON¡¡for¡¡terraforming¡¡other¡¡worlds£»¡¡this¡¡greatest¡¡of¡¡engineering¡¡projects¡¡might¡¡be¡¡feasible¡¡on¡¡the¡¡timescale¡¡we've¡¡been¡¡describing¡ªcertainly¡¡for¡¡asteroids£»¡¡possibly¡¡for¡¡Mars£»¡¡Titan£»¡¡and¡¡other¡¡moons¡¡of¡¡the¡¡outer¡¡planets£»¡¡and¡¡probably¡¡not¡¡for¡¡Venus¡£¡¡Pollack¡¡and¡¡I¡¡recognized¡¡that¡¡there¡¡are¡¡those¡¡who¡¡feel¡¡a¡¡powerful¡¡attraction¡¡to¡¡the¡¡idea¡¡of¡¡rendering¡¡other¡¡worlds¡¡in¡¡the¡¡Solar¡¡System¡¡suitable¡¡for¡¡human¡¡habitation¡ªin¡¡establishing¡¡observatories£»¡¡exploratory¡¡bases£»¡¡munities£»¡¡and¡¡homesteads¡¡there¡£¡¡Because¡¡of¡¡its¡¡pioneering¡¡history£»¡¡this¡¡may¡¡be¡¡a¡¡particularly¡¡natural¡¡and¡¡attractive¡¡idea¡¡in¡¡the¡¡United¡¡States¡£

In¡¡any¡¡case£»¡¡massive¡¡alteration¡¡of¡¡the¡¡environments¡¡of¡¡other¡¡worlds¡¡can¡¡be¡¡done¡¡petently¡¡and¡¡responsibly¡¡only¡¡when¡¡we¡¡have¡¡a¡¡much¡¡better¡¡understanding¡¡of¡¡those¡¡worlds¡¡than¡¡is¡¡available¡¡today¡£¡¡Advocates¡¡of¡¡terraforming¡¡must¡¡first¡¡bee¡¡advocates¡¡of¡¡the¡¡long¡­term¡¡and¡¡thorough¡¡scientific¡¡exploration¡¡of¡¡other¡¡worlds¡£

Perhaps¡¡when¡¡we¡¡really¡¡understand¡¡the¡¡difficulties¡¡of¡¡terraforming£»¡¡the¡¡costs¡¡or¡¡the¡¡environmental¡¡penalties¡¡will¡¡prove¡¡too¡¡steep£»¡¡and¡¡we¡¡will¡¡lower¡¡our¡¡sights¡¡to¡¡domed¡¡or¡¡subsurface¡¡cities¡¡or¡¡other¡¡local£»¡¡closed¡¡ecological¡¡systems£»¡¡greatly¡¡improved¡¡versions¡¡of¡¡Biosphere¡¡II£»¡¡on¡¡other¡¡worlds¡£¡¡Perhaps¡¡we¡¡will¡¡abandon¡¡the¡¡dream¡¡of¡¡converting¡¡the¡¡surfaces¡¡of¡¡other¡¡worlds¡¡to¡¡something¡¡approaching¡¡the¡¡Earth's¡£¡¡Or¡¡perhaps¡¡there¡¡are¡¡much¡¡more¡¡elegant£»¡¡cost¡­effective£»¡¡and¡¡environmentally¡¡responsible¡¡ways¡¡of¡¡terraforming¡¡that¡¡we¡¡have¡¡not¡¡yet¡¡imagined¡£

But¡¡if¡¡we¡¡are¡¡seriously¡¡to¡¡pursue¡¡the¡¡matter£»¡¡certain¡¡questions¡¡ought¡¡to¡¡be¡¡asked£º¡¡Given¡¡that¡¡any¡¡terraforming¡¡scheme¡¡entails¡¡a¡¡balance¡¡of¡¡benefits¡¡against¡¡costs£»¡¡how¡¡certain¡¡must¡¡we¡¡be¡¡that¡¡key¡¡scientific¡¡information¡¡will¡¡not¡¡thereby¡¡be¡¡destroyed¡¡before¡¡proceeding£¿¡¡How¡¡much¡¡understanding¡¡of¡¡the¡¡world¡¡in¡¡question¡¡do¡¡we¡¡need¡¡before¡¡planetary¡¡engineering¡¡can¡¡be¡¡relied¡¡upon¡¡to¡¡produce¡¡the¡¡desired¡¡end¡¡state£¿¡¡Can¡¡we¡¡guarantee¡¡a¡¡long¡­term¡¡human¡¡mitment¡¡to¡¡maintain¡¡and¡¡replenish¡¡an¡¡engineered¡¡world£»¡¡when¡¡human¡¡political¡¡institutions¡¡are¡¡so¡¡short¡¡lived£¿¡¡If¡¡a¡¡world¡¡is¡¡even¡¡conceivably¡¡inhabited¡ªperhaps¡¡only¡¡by¡¡microorganisms¡ªdo¡¡humans¡¡have¡¡a¡¡right¡¡to¡¡alter¡¡it£¿¡¡What¡¡is¡¡our¡¡responsibility¡¡to¡¡preserve¡¡the¡¡worlds¡¡of¡¡the¡¡Solar¡¡System¡¡in¡¡their¡¡present¡¡wilderness¡¡states¡¡for¡¡future¡¡generations¡­who¡¡may¡¡contemplate¡¡uses¡¡that¡¡today¡¡we¡¡are¡¡too¡¡ignorant¡¡to¡¡foresee£¿¡¡These¡¡questions¡¡may¡¡perhaps¡¡be¡¡encapsulated¡¡into¡¡a¡¡final¡¡question£º¡¡Can¡¡we£»¡¡who¡¡have¡¡made¡¡such¡¡a¡¡mess¡¡of¡¡this¡¡world£»¡¡be¡¡trusted¡¡with¡¡others£¿

It¡¡is¡¡just¡¡conceivable¡¡that¡¡some¡¡of¡¡the¡¡techniques¡¡that¡¡might¡¡eventually¡¡terraform¡¡other¡¡worlds¡¡might¡¡be¡¡applied¡¡to¡¡ameliorate¡¡the¡¡damage¡¡we¡¡have¡¡done¡¡to¡¡this¡¡one¡£¡¡Considering¡¡the¡¡relative¡¡urgencies£»¡¡a¡¡useful¡¡indication¡¡of¡¡when¡¡the¡¡human¡¡species¡¡is¡¡ready¡¡to¡¡consider¡¡terraforming¡¡seriously¡¡is¡¡when¡¡we¡¡have¡¡put¡¡our¡¡own¡¡world¡¡right¡£¡¡We¡¡can¡¡consider¡¡it¡¡a¡¡test¡¡of¡¡the¡¡depth¡¡of¡¡our¡¡understanding¡¡and¡¡our¡¡mitment¡£¡¡The¡¡first¡¡step¡¡in¡¡engineering¡¡the¡¡Solar¡¡System¡¡is¡¡to¡¡guarantee¡¡the¡¡habitability¡¡of¡¡the¡¡Earth¡£

Then¡¡we'll¡¡be¡¡ready¡¡to¡¡spread¡¡out¡¡to¡¡asteroids£»¡¡ets£»¡¡Mars£»¡¡the¡¡moons¡¡of¡¡the¡¡outer¡¡Solar¡¡System£»¡¡and¡¡beyond¡£¡¡Jack¡¡Williamson¡¡'s¡¡prediction¡¡that¡¡this¡¡will¡¡begin¡¡to¡¡e¡¡about¡¡by¡¡the¡¡twenty¡­second¡¡century¡¡may¡¡not¡¡be¡¡far¡¡off¡¡the¡¡mark¡£



THE¡¡NOTION¡¡OF¡¡OUR¡¡DESCENDANTS¡¡living¡¡and¡¡working¡¡on¡¡other¡¡worlds£»¡¡and¡¡even¡¡moving¡¡some¡¡of¡¡them¡¡around¡¡for¡¡their¡¡convenience£»¡¡seems¡¡the¡¡most¡¡extravagant¡¡science¡¡fiction¡£¡¡Be¡¡realistic£»¡¡a¡¡voice¡¡inside¡¡my¡¡head¡¡counsels¡£¡¡But¡¡this¡¡is¡¡realistic¡£¡¡We're¡¡on¡¡the¡¡cusp¡¡of¡¡the¡¡technology£»¡¡near¡¡the¡¡midpoint¡¡between¡¡impossible¡¡and¡¡routine¡£¡¡It's¡¡easy¡¡to¡¡be¡¡conflicted¡¡about¡¡it¡£¡¡If¡¡we¡¡don't¡¡do¡¡something¡¡awful¡¡to¡¡ourselves¡¡in¡¡the¡¡interim£»¡¡in¡¡another¡¡century¡¡terraforming¡¡may¡¡seem¡¡no¡¡more¡¡impossible¡¡than¡¡a¡¡human¡­tended¡¡space¡¡station¡¡does¡¡today¡£

I¡¡think¡¡the¡¡experience¡¡of¡¡living¡¡on¡¡other¡¡worlds¡¡is¡¡bound¡¡to¡¡change¡¡us¡£¡¡Our¡¡descendants£»¡¡born¡¡and¡¡raised¡¡elsewhere£»¡¡will¡¡naturally¡¡begin¡¡to¡¡owe¡¡primary¡¡loyalty¡¡to¡¡the¡¡worlds¡¡of¡¡their¡¡birth£»¡¡whatever¡¡affection¡¡they¡¡retain¡¡for¡¡the¡¡Earth¡£¡¡Their¡¡physical¡¡needs£»¡¡their¡¡methods¡¡of¡¡supplying¡¡those¡¡needs£»¡¡their¡¡technologies£»¡¡and¡¡their¡¡social¡¡structures¡¡will¡¡all¡¡have¡¡to¡¡be¡¡different¡£

A¡¡blade¡¡of¡¡grass¡¡is¡¡a¡¡monplace¡¡on¡¡Earth£»¡¡it¡¡would¡¡be¡¡a¡¡miracle¡¡on¡¡Mars¡£¡¡Our¡¡descendants¡¡on¡¡Mars¡¡will¡¡know¡¡the¡¡value¡¡of¡¡a¡¡patch¡¡of¡¡green¡£¡¡And¡¡if¡¡a¡¡blade¡¡of¡¡grass¡¡is¡¡priceless£»¡¡what¡¡is¡¡the¡¡value¡¡of¡¡a¡¡human¡¡being£¿¡¡The¡¡American¡¡revolutionary¡¡Tom¡¡Paine£»¡¡in¡¡describing¡¡his¡¡contemporaries£»¡¡had¡¡thoughts¡¡along¡¡these¡¡lines£º

The¡¡wants¡¡which¡¡necessarily¡¡acpany¡¡the¡¡cultivation¡¡of¡¡a¡¡wilderness¡¡produced¡¡among¡¡them¡¡a¡¡state¡¡of¡¡society¡¡which¡¡countries¡¡long¡¡harassed¡¡by¡¡the¡¡quarrels¡¡and¡¡intrigues¡¡of¡¡governments¡¡had¡¡neglected¡¡to¡¡cherish¡£¡¡In¡¡such¡¡a¡¡situation¡¡man¡¡bees¡¡what¡¡he¡¡ought¡¡to¡¡be¡£¡¡He¡¡sees¡¡his¡¡species¡¡¡£¡¡¡£¡¡¡£¡¡as¡¡kindred¡£

Having¡¡seen¡¡at¡¡first¡¡hand¡¡a¡¡procession¡¡of¡¡barren¡¡and¡¡desolate¡¡worlds£»¡¡it¡¡will¡¡be¡¡natural¡¡for¡¡our¡¡spacefaring¡¡descendants¡¡to¡¡cherish¡¡life¡£¡¡Having¡¡learned¡¡something¡¡from¡¡the¡¡tenure¡¡of¡¡our¡¡species¡¡on¡¡Earth£»¡¡they¡¡may¡¡wish¡¡to¡¡apply¡¡those¡¡lessons¡¡to¡¡other¡¡worlds¡ªto¡¡spare¡¡generations¡¡to¡¡e¡¡the¡¡avoidable¡¡suffering¡¡that¡¡their¡¡ancestors¡¡were¡¡obliged¡¡to¡¡endure£»¡¡and¡¡to¡¡draw¡¡upon¡¡our¡¡experience¡¡and¡¡our¡¡mistakes¡¡as¡¡we¡¡begin¡¡our¡¡open¡­ended¡¡evolution¡¡into¡¡space¡£




CHAPTER¡¡20¡¡¡¡¡¡DARKNESS

¡¡

¡¡

Far¡¡away£»¡¡hidden¡¡from¡¡the¡¡eyes¡¡of¡¡daylight£»¡¡there¡¡are¡¡watchers¡¡in¡¡the¡¡skies¡£

¡ªEURIPIDES£»¡¡THE¡¡BACCHAE¡¡£¨CA¡£¡¡406¡¡B¡£C¡££©

As¡¡children£»¡¡we¡¡fear¡¡the¡¡dark¡£¡¡Anything¡¡might¡¡be¡¡out¡£¡¡here¡£¡¡The¡¡unknown¡¡troubles¡¡us¡£¡¡Ironically£»¡¡it¡¡is¡¡our¡¡fate¡¡to¡¡live¡¡in¡¡the¡¡dark¡£¡¡This¡¡unexpected¡¡finding¡¡of¡¡science¡¡is¡¡only¡¡about¡¡three¡¡centuries¡¡old¡£¡¡Head¡¡out¡¡from¡¡the¡¡Earth¡¡in¡¡any¡¡direction¡¡you¡¡choose£»¡¡and¡ªafter¡¡an¡¡initial¡¡flash¡¡of¡¡blue¡¡and¡¡a¡¡longer¡¡wait¡¡while¡¡the¡¡Sun¡¡fades¡ªyou¡¡are¡¡surrounded¡¡by¡¡blackness£»¡¡punctuated¡¡only¡¡here¡¡and¡¡there¡¡by¡¡the¡¡faint¡¡and¡¡distant¡¡stars¡£

Even¡¡after¡¡we¡¡are¡¡grown£»¡¡the¡¡darkness¡¡retains¡¡its¡¡power¡¡to¡¡frighten¡¡us¡£¡¡And¡¡so¡¡there¡¡are¡¡those¡¡who¡¡say¡¡we¡¡should¡¡not¡¡inquire¡¡too¡¡closely¡¡into¡¡who¡¡else¡¡might¡¡be¡¡living¡¡in¡¡that¡¡darkness¡£¡¡Better¡¡not¡¡to¡¡know£»¡¡they¡¡say¡£

There¡¡are¡¡400¡¡billion¡¡stars¡¡in¡¡the¡¡Milky¡¡Way¡¡Galaxy¡£¡¡Of¡¡this¡¡immense¡¡multitude£»¡¡could¡¡it¡¡be¡¡that¡¡our¡¡humdrum¡¡Sun¡¡is¡¡the¡¡only¡¡one¡¡with¡¡an¡¡inhabited¡¡planet£¿¡¡Maybe¡£¡¡Maybe¡¡the¡¡origin¡¡of¡¡life¡¡or¡¡intelligence¡¡is¡¡exceedingly¡¡improbable¡£¡¡Or¡¡maybe¡¡civilizations¡¡arise¡¡all¡¡the¡¡time£»¡¡but¡¡wipe¡¡themselves¡¡out¡¡as¡¡soon¡¡as¡¡they¡¡are¡¡able¡£

Or£»¡¡here¡¡and¡¡there£»¡¡peppered¡¡across¡¡space£»¡¡orbiting¡¡other¡¡suns£»¡¡maybe¡¡there¡¡are¡¡worlds¡¡something¡¡like¡¡our¡¡own£»¡¡on¡¡which¡¡other¡¡beings¡¡gaze¡¡up¡¡and¡¡wonder¡¡as¡¡we¡¡do¡¡about¡¡who¡¡else¡¡lives¡¡in¡¡the¡¡dark¡£¡¡Could¡¡the¡¡Milky¡¡Way¡¡be¡¡rippling¡¡with¡¡life¡¡and¡¡intelligence¡ªworlds¡¡calling¡¡out¡¡to¡¡worlds¡ªwhile¡¡we¡¡on¡¡Earth¡¡are¡¡alive¡¡at¡¡the¡¡critical¡¡moment¡¡when¡¡we¡¡first¡¡decide¡¡to¡¡listen£¿

Our¡¡species¡¡has¡¡discovered¡¡a¡¡way¡¡to¡¡municate¡¡through¡¡the¡¡dark£»¡¡to¡¡transcend¡¡immense¡¡distances¡£¡¡No¡¡means¡¡of¡¡munication¡¡is¡¡faster¡¡or¡¡cheaper¡¡or¡¡reaches¡¡out¡¡farther¡£¡¡It's¡¡called¡¡r
СÌáʾ£º°´ »Ø³µ [Enter] ¼ü ·µ»ØÊéÄ¿£¬°´ ¡û ¼ü ·µ»ØÉÏÒ»Ò³£¬ °´ ¡ú ¼ü ½øÈëÏÂÒ»Ò³¡£ ÔÞһϠÌí¼ÓÊéÇ©¼ÓÈëÊé¼Ü