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irlpool　Nebula；　or　Centaurus　A；　or　the　Virgo　cluster　of　galaxies；　or　the　nearest　Seyfert　galaxies；　none　among　any　of　the　hundred　trillion　stars　in　thousands　of　nearby　galaxies。　Stake　through　its　heart　or　not；　the　geocentric　conceit　stirs　again。

Of　course；　it　might　be　a　token　not　of　intelligence　but　of　stupidity　to　pour　so　much　energy　into　interstellar　（and　intergalactic）　munication。　Perhaps　they　have　good　reasons　not　to　hail　all　ers。　Or　perhaps　they　don't　care　about　civilizations　as　backward　as　we　are。　But　still—not　one　civilization　in　a　hundred　trillion　stars　broadcasting　with　such　power　on　such　a　frequency？　If　the　META　results　are　negative；　we　have　set　an　instructive　limit—but　whether　on　the　abundance　of　very　advanced　civilizations　or　their　munications　strategy　we　have　no　way　of　knowing。　Even　if　META　has　found　nothing；　a　broad　middle　range　remains　open—of　abundant　civilizations；　more　advanced　than　we　and　broadcasting　omnidirectionally　at　magic　frequencies。　We　would　not　have　heard　from　them　yet。



ON　OCTOBER　12；　1992—auspiciously　or　otherwise　the　500th　anniversary　of　the　〃discovery〃　of　America　by　Christopher　Columbus—NASA　turned　on　its　new　SETI　program。　At　a　radio　telescope　in　the　Mojave　Desert；　a　search　was　initiated　intended　to　cover　the　entire　sky　systematically—like　META；　making　no　guesses　about　which　stars　are　more　likely；　but　greatly　expanding　the　frequency　coverage。　At　the　Arecibo　Observatory；　an　even　more　sensitive　NASA　study　began　that　concentrated　on　promising　nearby　star　systems。　When　fully　operational；　the　NASA　searches　would　have　been　able　to　detect　much　fainter　signals　than　META；　and　look　for　kinds　of　signals　that　META　could　not。

The　META　experience　reveals　a　thicket　of　background　static　and　radio　interference。　Quick　reobservation　and　confirmation　of　the　signal—specially　at　other；　independent　radio　telescopes—is　the　key　to　being　sure。　Horowitz　and　I　gave　NASA　scientists　the　coordinates　of　our　fleeting　and　enigmatic　events。　Perhaps　they　would　be　able　to　confirm　and　clarify　our　results。　The　NASA　program　was　also　developing　new　technology；　stimulating　ideas；　and　exciting　schoolchildren。　In　the　eyes　of　many　it　was　well　worth　the　10　million　a　year　being　spent　on　it。　But　almost　exactly　a　year　after　authorizing　it；　Congress　pulled　the　plug　on　NASA's　SETI　program。　It　cost　too　much；　they　said。　The　post…Cold　War　U。S。　defense　budget　is　some　30；000　times　larger。

The　chief　argument　of　the　principal　opponent　of　the　NASA　SETI　program—Senator　Richard　Bryan　of　Nevada—was　this　＇from　the　Congressional　Record　for　September　22；　1993＇：

So　far；　the　NASA　SETI　Program　has　found　nothing。　In　fact；　all　the　decades　of　SETI　research　have　found　no　confirmable　signs　of　extraterrestrial　life。

Even　with　the　current　NASA　version　of　SETI；　I　do　not　think　many　of　its　scientists　would　be　willing　to　guarantee　that　we　are　likely　to　see　any　tangible　results　in　the　＇foreseeable＇　future　。　。　。

Scientific　research　rarely；　if　ever；　offers　guarantees　of　success—and　I　understand　that—and　the　full　benefits　of　such　research　are　often　unknown　until　very　late　in　the　process。　And　I　accept　that；　as　well。

In　the　case　of　SETI；　however；　the　chances　of　success　are　so　remote；　and　the　likely　benefits　of　the　program　are　so　limited；　that　there　is　little　justification　for　12　million　taxpayer　dollars　to　be　expended　for　this　program。

But　how；　before　we　have　found　extraterrestrial　intelligence；　can　we　〃guarantee〃　that　we　will　find　it？　How；　on　the　other　hand；　can　we　know　that　the　chances　of　success　are　〃remote〃？　And　if　we　find　extraterrestrial　intelligence；　are　the　benefits　really　likely　to　be　〃so　limited〃？　As　in　all　great　exploratory　ventures；　we　do　not　know　what　we　will　find　and　we　don't　know　the　probability　of　finding　it。　If　we　did；　we　would　not　have　to　look。

SETI　is　one　of　those　search　programs　irritating　to　those　who　want　well…defined　cost/benefit　ratios。　Whether　ETI　can　be　found；　how　long　it　would　take　to　find　it；　and　what　it　would　cost　to　do　so　are　all　unknown。　The　benefits　might　be　enormous；　but　we　can't　really　be　sure　of　that　either。　It　would　of　course　be　foolish　to　spend　a　major　fraction　of　the　national　treasure　on　such　ventures；　but　I　wonder　if　civilizations　cannot　be　calibrated　by　whether　they　pay　some　attention　to　trying　to　solve　the　great　problems。

Despite　these　setbacks；　a　dedicated　band　of　scientists　and　engineers；　centered　at　the　SETI　Institute　in　Palo　Alto；　California；　has　decided　to　go　ahead；　government　or　no　government。　NASA　has　given　them　permission　to　use　the　equipment　already　paid　for；　captains　of　the　electronics　industry　have　donated　a　few　million　dollars；　at　least　one　appropriate　radio　telescope　is　available；　and　the　initial　stages　of　this　grandest　of　all　SETI　programs　is　on　track。　If　it　can　demonstrate　that　a　useful　sky　survey　is　possible　without　being　swamped　by　background　noise—and　especially　if；　as　is　very　likely　from　the　META　experience；　there　are　unexplained　candidate　signals…perhaps　Congress　will　change　its　mind　once　more　and　fund　the　project。

Meanwhile；　Paul　Horowitz　has　e　up　with　a　new　program—different　from　META；　different　from　what　NASA　was　doing—called　BETA。　BETA　stands　for　〃Billion…channel　ExtraTerrestrial　Assay。〃　It　bines　narrow…band　sensitivity；　wide　frequency　coverage；　and　a　clever　way　to　verify　signals　as　they're　detected。　If　The　Planetary　Society　can　find　the　additional　support；　this　system—much　cheaper　than　the　former　NASA　program—should　be　on　the　air　soon。



WOULD　I　LIKE　TO　BELIEVE　that　with　META　we've　detected　transmissions　from　other　civilizations　out　there　in　the　dark；　sprinkled　through　the　vast　Milky　Way　Galaxy？　You　bet。　After　decades　of　wondering　and　studying　this　problem；　of　course　I　would。　To　me；　such　a　discovery　would　be　thrilling。　It　would　change　everything。　We　would　be　hearing　from　other　beings；　independently　evolved　over　billions　of　years；　viewing　the　Universe　perhaps　very　differently；　probably　much　smarter；　certainly　not　human。　How　much　do　they　know　that　we　don't？

For　me；　no　signals；　no　one　calling　out　to　us　is　a　depressing　prospect。　〃plete　silence；〃　said　Jean…Jacques　Rousseau　in　a　different　context；　〃induces　melancholy；　it　is　an　image　of　death。〃　But　I'm　with　Henry　David　Thoreau：　〃Why　should　I　feel　lonely？　Is　not　our　planet　in　the　Milky　Way？〃

The　realization　that　such　beings　exist　and　that；　as　the　evolutionary　process　requires；　they　must　be　very　different　from　us；　would　have　a　striking　implication：　Whatever　differences　divide　us　down　here　on　Earth　are　trivial　pared　to　the　differences　between　any　of　us　and　any　of　them。　Maybe　it's　a　long　shot；　but　the　discovery　of　extraterrestrial　intelligence　might　play　a　role　in　unifying　our　squabbling　and　divided　planet。　It　would　be　the　last　of　the　Great　Demotions；　a　rite　of　passage　for　our　species　and　a　transforming　event　in　the　ancient　quest　to　discover　our　place　in　the　Universe。

In　our　fascination　with　SETI；　we　might　be　tempted；　even　without　good　evidence；　to　succumb　to　belief　but　this　would　be　self…indulgent　and　foolish。　We　must　surrender　our　skepticism　only　in　the　face　of　rock…solid　evidence。　Science　demands　a　tolerance　for　ambiguity。　Where　we　are　ignorant；　we　withhold　belief。　Whatever　annoyance　the　uncertainty　engenders　serves　a　higher　purpose：　It　drives　us　to　accumulate　better　data。　This　attitude　is　the　difference　between　science　and　so　much　else。　Science　offers　little　in　the　way　of　cheap　thrills。　The　standards　of　evidence　are　strict。　But　when　followed　they　allow　us　to　see　far；　illuminating　even　a　great　darkness。




CHAPTER　21　　　TO　THE　SKY！

　

　

The　stairs　of　the　sky　are　let　down　for　him　that　he　may　ascend　thereon　to　heaven。　O　gods；　put　your　arms　under　the　king：　raise　him；　lift　him　to　the　sky。　To　the　sky！　To　the　sky！

—HYMN　FOR　A　DEAD　PHARAOH　（EGYPT；　CA。　2600　B。C。）

When　my　grandparents　were　children；　the　electric　light；　the　automobile；　the　airplane；　and　the　radio　were　Stupefying　technological　advances；　the　wonders　of　the　age。　You　might　hear　wild　stories　about　them；　but　you　could　not　find　a　single　exemplar　in　that　little　village　in　Austria…Hungary；　near　the　banks　of　the　river　Bug。　But　in　that　same　time；　around　the　turn　of　the　last　century；　there　were　two　men　who　foresaw　other；　far　more　ambitious；　inventions—Konstantin　Tsiolkovsky；　the　theoretician；　a　nearly　deaf　schoolteacher　in　the　obscure　Russian　town　of　Kaluga；　and　Robert　Goddard；　the　engineer；　a　professor　at　an　equally　obscure　American　college　in　Massachusetts。　They　dreamt　of　using　rockets　to　journey　to　the　planets　and　the　stars。　Step　by　step；　they　worked　out　the　fundamental　physics　and　many　of　the　details。　Gradually；　their　machines　took　shape。　Ultimately；　their　dream　proved　infectious。

In　their　time；　the　very　idea　was　considered　disreputable；　or　even　a　symptom　of　some　obscure　derangement。　Goddard　found　that　merely　mentioning　a　voyage　to　other　worlds　subjected　him　to　ridicule；　and　he　dared　not　publish　or　even　discuss　in　public　his　long…term　vision　of　flights　to　the　stars。　As　teenagers；　both　had　epiphanal　visions　of　spaceflight　that　never　left　them。　〃I　still　have　dreams　in　which　I　fly　up　to　the　stars　in　my　machine；〃　Tsiolkovsky　wrote　in　middle　age。　〃It　is　difficult　to　work　all　on　your　own　for　many　years；　in　adverse　conditions　without　a　gleam　of　ho