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GROU]VD-BASED ASTRONOMT A TE]V-TEAR PROGRATVT REPORT PREPARED BY THE PANEL ON ASTRONOMICAL FACILITIES A FOR THE COMMITTEE ON SCIENCE Al:lD PUBLIC POLIC'( OF THE NATIONAL ACADEMY OF SCIENCES NATIONAL ACADEMY OF SCIENCES-NATIONAL RESEARCH COUNCIL (: w f) lAA¿ ^c.urNtlT¡)N Copyright © National Academy of Sciences. All rights reserved.
Endsheet: A portiarù of th.e Netu)otk Nebulø irL Cggnus, photogaphad, toÃth the 4\-inah Schmtd,t telescope ol the Mount Wllsotu and Pølþñ.øl Obse¡oøto¡Ães. The bop struc-ture i.s conposeil of the debrìs of a supernoþø erplos.¡oÃù nanv thousands ol geørs øgo. Rad.ia tel.escopes d,etea., the strongest rad,ÃatÃon ftumthe cenfer of the looþ. prÃntÃng 1966, aìth Second, reoìsed, Appendk. LÃbørg of Congess catatog nttmbet 64-62266 et 7234 P ublication N urnb Pri,ce: $4.O0 Copyright © National Academy of Sciences. All rights reserved.
w FI ffi li 1:i I August 19, 7964 Dear Dr. SeÃtz: The Comrnittee on Science anil, Public Poliat¿, on the basis of careful stuilg of thi.s report and, extensioe d,iscussion lDith its authors, is plnased to endorse Ãt to you for transmiflal. The report deals uith grounil-baseil astronomical facÃ¥IitÃes ercl:usioelg. It recommend,s ôertain neû facilities, to be acquired at a. rate based, on an in- temnl criterion--a consewatû)e esti'nnte of the rate at tohich astuonomical progtess can be made. We bekeae thnt this k the rìght aytproach to be adopted by panels of experts y:repøring 'plnnningi reports, i.e., reports on the oppor- tunities a.nd, needs of aaúous f,el.ds of science. Determhlat¿on of the optixrutm balance of the scáences as u.tell as the oaer-all ro,te of scienti.frc progress needed for achóetsing twtional goals requires mønq authoritatiÃe inputs of informati.on ïel.e.ti,ng to the aari,ous sciencøs, and the iudgment of people concet ned løith rwti.ornl policies. We are corwince¿J that the present rcport ôonstitutes a oetA sound input for such d,etermirntion. The report presents an excellently balnnced, program for nea facôlÃties of ground.-bøsed. astronomV i.n the neú decad.e, uell justif,ed, by the i,mportant scientìfrc opportunities brìeflg d,iscussed, in the report. The care uith ushich radio and, optica,l progra.ms haoe been interuoùen anil the sel.ection of facikti.es at oarì,ous le¡sels to sttit the eqJected, spectrum of research and, teachöng actiDitìes are especially noteaot'thV. A good deal of care appears also to haoe gone into the consideratÃon of lhe indÃuidual items of the progtam. Wi,th rcgard, to rud,ioaÃtronomì,cal facilities, the Commirtea on Science and Pubkc Policy Ã,s aware that Ãn the past some x.ùstantiallg loú cost estimates haoe been made, eoen bg øxpørt oÃbonomical engineers. The situation has improoed ¿n Ãecent gears, houeoer, aniL seoeral maior facÃlities (q 300-foot dish telescope, neu; \S-foot dtÃshes, and, some millimeter uaoe telescopes) haoe been com.pleted' at costs vþÃthin a feü percentd.ge poi,nts ol the original estimates. A great deal of care uent into ihe cost estÃmates of the facilities proposed here, and ue haoe Copyright © National Academy of Sciences. All rights reserved.
of thøse lacölìfies øre quite to no grúnd.s qüestÃ.on the rcMltant figures. Some adoanned, honseoer, anil ue loin the authors of the rcport in rccommending that further d,etail,ed cost estimntes be unilertaken pÿoà to d'ecÃsionà irusolaing such facilitips. The total scope ol the fanilifies program appears oery ieasornbl'e and ueII iustifieil bg tha promises of radin a.stronomy. Wöth îegard to optbal faciliti,es ae frnd that the recommendeil plan is ilefinìtelg conseraatû)e. ln fact, if u:e hnoe anE il,oubts at all, it ìà that ìt înaA err on the side of conseraatism bg not proaìding tufrciønt opportunities for the grousÃ,ng rwmbø of goung asttonomers at the gadlnte leael ønil, slightfu beEonÃ¥ to nnke uÃe of f.rst-cbss research facilifies. We are also not sure that the pro- poseil facilities and &tpporti,ng inÃtrumentetion, uhich clea g rcquite røpiìl ileoelopment, toould, be adequ.ate to peÃmit their efiectitse use by groups closelE relateil to aÃfionom7 an¿l Aet not quite an integTal palt ol if' We mean, for instance, sc¿entists usho are concemeil wìth the denils of planetarg strachtre and compositÃon. The Panel thnt prepare¿l thià røport uas requested to concern üself pri- marilE uðth astronomìral facilities. The report, houeoer, includ,es a bù'øf sectinn in ushich estômates of the annunl costs of scielntif,c actioities, uhÃch are additi'oe to the cos'ts of facilit¿es and thøh mnintenonce, are prøsented. The Panefs stud'g of this subiect uas considerablg less d,etailød than its studA of facikties rcquöre' ments, but ue belieoe tlnt the findings are quiie rcasonable and' aïe consistent u;ith the proposed plnn for facÃkties. The rcport rightlg emphasÃzes o.s'tronomy as a pure scÃence. lts søeep granileur hnoe had. an inner fasctuntion for all peopln at all thnes and Ãs anil certain to haoe if in the-Ãuture. We utould be remiss if u.:e iliil not note 1Dáth the Panel the mnior contri.bütÃons of astronomA to other sciences-for emmpl'e, the d,iscoaerg of heltum and, the contri,butians to the problem of thermonucleat rcactÃons. Clearly the fed.eral agencg ûhose activities u:iLl be most dôrectly affecteil by rcsearch ûith the heþ of nea østuonotnical fac¿lties is thø National Aero' nautics and, Space Ad.ministration. The connection betuseen the swbiect matter of the Nøtional Aercrwutics an'il Space Ad'mìnishatiois interest and the intetests of g¡otq4d-based astronomy is cloqe, not onlg in the uell;recognized. problems of the sol sustern, but in the eEnllE exciting areas of interstellar partü:les and Copyright © National Academy of Sciences. All rights reserved.
fielãs, uløaoiolet railiation of the stars, anil radio, X+ag, and gamma-raV energ7 sources. The Natiornl Aerorm.tics and Space Administîation Ã, in fact, engaged in alJ these field.s uith its orbiting erperáments. The natiorÃs neulg gaineiL tech- nologg of ertrateîrestrìa.l a:tronom7 mtkes ìt hnperatûse that the knouleilge tlwt can be had, from the ground in these arcas be pushe.d ahead, as fast øs possible so th.at the spaæ effort aill h^aae the strongest possible back-up. A mooe bg thn Nationi.l Aercrrtutics and, Space Administuation to broaden its alreadE sfiong interest in basic astronomical research so as to includ,e grounil,-based, stellar astronomA uoulà , be highlg aiLaantageous to the national scÃentifrc effort anÃ¥ to the Natianal Aerotwutács and Space Administration itself- The keen and, uell- itÃtifie¿I interest of the National Aerorwttics and Space Ad,ministration in the traÃning of space scÃentists coulil, toell be extend,ed to assiÃtance anil ðnuease in fani.lifies for ølI astronomy, because the space ønd, ground,-based, actioities of østronomers are but the tuo faces of the same coin. The National Science Foundntion has gioen the broadest poss:ible support to resea.rch i,n q.stronomV; the Foundntion and the. Office of Narsal Research haoe been the princùpal channels for Fed,eral participation in the &tppoú of thà research. lt is essential th(û the broad. sup,port from these sources, uhöch constitutes so Dilal a contribution to the adaancement of artronomy, be continued^ The Nati,onal Science Foundation anìl the Office of Naaal Research, together uith the Nøtional Aercrwutics and Spacø AdmÃ,nÃtratÃon, coul"d, form a strong gouetn- ment ted.m thnt uould cørry (rstronom7 foruard, on all fronts, by means of a bal- anced, program of wpport of alJ eLements along the lines enaÃÃoned, in this report. ln conclt¿sion, ûe ûÃh to recommend, a cøreful stuìlg o! thi.s report and. the adoption of its recommendatiotà to those. u;ho are concerned usith fed,eral pl.anning of suppott of science; Ãt is a carrtullg prepared ønd, toell-conceioed document. We extend our complÃ,merús on a iob u:ell ìl,one to all those u.tho particip(úe¿l in its preparation, and, especiallE to the chafumnn ønd, members of the Panel, uho deooted, maior perconal efrort to this r eport. Sincerelg yours, G. B. Kistiakou:skE FOR THE COMMITTEE ON SCIENCE A.ND PUBLIC POLICY iL Copyright © National Academy of Sciences. All rights reserved.
tï iì I l Since its foun¿l,ing in 7863, the Academg has hail, a ileep Ã¥nterest ground-based dstronomA. Benjamin A. Goul.d, a chnrter member in of the Acail.emg, uaà an interrntionally famous aatronþmer ol hà ilny. George Ellerg Hal.e, the first chairman of the National Research Coun- cil, u,vs enormotælg efiectioe in ad,oancÃng a.stronomg itù our countrA to a leaìling posátion in uo à astronomg. ln continu&tion oà thià interest the Acadenry s Commöttee on Science anil Pubkc Pokcg undertook a studg of the need for facilities in this field. It is a priailege to make their usork krnun. FreilerÃck Sei.tz PRESIDENT NÃTIONAI ÃCADEMY OF SCIENCES Washington, D.C August 25, 1964 Copyright © National Academy of Sciences. All rights reserved.
PANEL ON ASTRONOMIC AL FAC¿LITIES A. E. Whìrlod. Chaì¡n¿n, Lìck Obseþatory, UdoeÃttv ol CaliÃomìa R. N, Braceroell BadÃo Astonomg Instì*ute-nadbscÿnca f-aboratory, StanÃoú, U¡¿aeîsÃtg Frcnk D. Dru*e, Depaúnetut oà Astroflomg, Comell IlnÃ.oerdtg F¡ed,e¡ì¿k T..Hød.dock, ln, Bødiø Astronamg Obsemøtorg, ÃlnioersÃt! of MtchÃEatu William LÃIl¿t Depørtn¿nt oà Asttonôrnq, HaQard, IlrltueÃit| W. W. Moryan,IeÃes ObsetuatoîV, lJnÃoeÃitV of Chlcago Btwe H. Rule, Calilonlìø In"tt¿tute of Technolagg Allan R, Sønùrye, Mt. Wdlson øn¿ palþñû ObseþatorÃes, CøIÃÃontì4 lflstÃtute o! Technolngg, Comegi¿ Inst¡tutìor! oà W øshÃngtotr COMMITTEE ON SC¡ENCE AND PUBLTC POLICY Ceorye B. Kisri¿koÃskg, IIaroard, IJnÃaeÃitV, Chahnøn Løuyence R. Blìnks, Stanfod, tJnÃaersÃtg H.W. Bode, BeIl Teløphone Laborcto¡ies Frank Brink, It., The RockeÃellet Instìtute Mellin Calþin, UnioeÃÃtg ol CalÃforrlta Frønk L. Horsfall, lr., Sloan-Ketterùrg InÃtitute for Cancer Research A. L. LehflÃrlger, The lohni Hopkìns fJniaersÃtg Saunderc Mo.c Lane, I]nÃ,Ãers¿ttJ oà Ch¿cago Ca PÃafrrnann, Broen |Jrlù)ersit! Alløn R. Sand,age, Moünt WilÃon and, Polona¡ Obsercato es HartE L. ShapÃro, Ameñcøn Museum of Natural HÃÃtoîV T. M. Sonneborn, Ind,Ãana UniDersìtV lohn Yerhoogen, UnÃoeÃÃt! oî Calilornla Abh M- We¡nbeÃ, Oak RÃdge National LaboraÃoru Robert E. Cîeen, NotÃonal Acad,ema oà Sci.ences, ErecutÃoe Secretarg Copyright © National Academy of Sciences. All rights reserved.
FOREWORD The Panel on Astronomical Facilities was established late in 1962 by the National Academy of Sciences as an actÃvià of the Academy's Committee on Science and Public Policy. The established purpose of the Panel was to study the probable need for major new astronomical facilities in the United States during the next ffve to ten years, and to recommend guiding princÃples and estimates of cost in order that federal fu¡ds might be em- ployed with maximum efficiency to promote advancement of astronomy in all its b¡anches. The members of the Panel, cbosen to be representative of the most active groups in both optical and radio astuonomy, have attemptetl to assess the dùection that the obsewational branch of the science is likeþ to take in the decade ahead, and to ¡ecommend a program of facilities that will build upon the strength ancl productivity that the American âstronomical community has already demonstrated. The study was conffned to grounil-based facilities. Investigations of the universe by telescopes carried above the ea¡th's aûnosphere are under the cognizance of review bodÃes considering various aspects of the national space program, and the Panel has not considered them to be within its stated purview. It has, however, given thought to the relative roles of orbiting and ground-based telescopes and to the proper divÃsion of tasks betwéen the two methods of observatÃon, in oriler to appraise any imbalance in support or emphasis tliat may exist. The Panel has been guided by the view that âstronomy is a branch of the physical sciences engaged in basic research of Copyright © National Academy of Sciences. All rights reserved.
the purest sort, haditionally motivated by the desire to Imow and und.er_ stand. It is true that astronomy has also provided economic or practical dividends such as navigation, guidance systems, aod the gatherinf of data that gpirle and support the national space program. Furthelnore, ashonomy has enriched all other sciences: examples ,tã dr" di."ou"rv of the element helium from observations of the sr::r; ttre recognition of thennonuclear reac_ tions as a source of energy and as an explanation of the origin of the ele_ ments; and rÃevelopment of a picture of the early history óf tlre earth_ important to both geology and biology. Nevertheless, thé panel has con_ sidered its assignment to be the formulation of a facilities program dictated by the orderþ development of observational astronomy ai a pure science, not tied to mission-oriented facilities that may be proviáed with other goals in mind. The Panel has sought to anive at a set of recommendations that will be_ reasonable and pr.udent, consistent with growth rates already estab- lished. The Panel has felq however, tïat these rational precautions should be secondary to its mâin charge: to recommend ground--based instruments that will enable astronomers to exploit the opportrmities that beckon-both age-old problems that are on the verge of yielding to observational attack and exciting new developments of transcendent importance. _ The support that the federal govemment gives to such a program is in the same category as that given to Ãnvestigatioà of the inte¡ioi ofihe earth, of the depths of the ocean, of tlie upper atmosphere, and incleed to thé e4lloratjon of space by orbiting vehicles. These efiorts are all consequences of the natural human desire to understand ttre larger aspècts o¡ mart's environment. To the non-specialist the far reaches of space and time investi. gated by the astronomer have widespread appeal. The panel believes that an Ãnvestment in ground-based astronomical facilities of the order of one half of I per cent of that going into the space efiort woulil be consistent with a balanced program of federal support for science. '--- 4 Copyright © National Academy of Sciences. All rights reserved.
tr fà t: ': , i l CON?EN?'S I INTRODUCTION AND GENERAL STATEMENT 1 I The Nature of Astronom\ l Deaelopment ol a World, Picture Role of the United States in Astronomical Research g Optìcal Astronomg 3 RadÃo A,stuorLorng 4 CurrentProblems 5 Creat¡on oà the ChemÃcal Elements 6 Neø Rnotoled,ge lrora Rødio Astîoñomv 6 Calaùzs Erplod,Ãng 6 I QuasïStetlat Radio Sources I The lnadequacg of Present FacìlÃties The Relntion of Ground,-Based, and Space Astronomu to TI THE PRESENT POSITTON IN GROUND-BASED ASTRoNoMy 13 Theoretù:ølAstrophVsics is Optical ArttonomA 14 Prcsent Doì¡t¡nant Posit¿on o! the Uûited, States 74 Ãoà Futøe Success 75 Th.e Limãting Føctol Asttonom| Radio 18 Pre$ent PosÃÃÃon of the United States 78 Need. lol Hteh Afleulø¡ Resoüttìnn 18 ResolutÃorl oà Rød¿o Gala*ies 79 Prcblem 20 Resoh¡Ãon ønd the CosmologÃcal Methods oà Achÿoing H¿Bh AngulÃt ResolutÃon 27 Collecting Area and Sidelobes as Limitr¿ng Factors 23 Parubolic Antennas 24 à -.- Copyright © National Academy of Sciences. All rights reserved.
The Dilzmmn of the Astuonomg Graduøte School in 1964 26 Mdnpotner Tlohthtg of Asaononets Coøpøted, to Trøinlng o! Other phgsteal Scientì.sts 29 U. S. Memberchtp lo the lrúeîrøtion¿l, Astronomhal Unìon 3l Graà u&te Stud,eÃt Populntlon in Ashonomg DepaÃhnent$ Sz A Prcie.tìon 35 TerÃYeat Conclusion 37 A PROGNAM FOR CONSTRUCTION OF OPTICAL TELESCOPES 38 Tgpes Neeiled sa Spea tl-Purpose Tel.escopes 39 SolarTebscopes 39 Categories 40 Si.z,e Perlotmnncø aersas Size 40 Big? HorD 42 Large Telescopes 42 Location of Large Telescopes a3 Under What Auspi.ces? 44 PteoÃous Pefiormance 44 lÃtst¡tution 44 Tgpe o1 Goal The Prlmar! 46 Engineeúng Studg for a Giant Tel.escope 46 Size Telescopes of Mod,erate 47 SmallTelescopes 48 Summary of Reconînendati,ons lor Opticøl Telescopes 49 N A PROGRAM FOR CONSTRUCTION OF RADIO TELESCOPES 50 A Maior High-Resolution lnstrument 50 A Hìgh-Resolution ArraE of Limited CapabilitA 62 Larye Parøboloids 5s lnstruments Smøller Special-Puîpose 54 DesÃgn Studg fot the Largest Possible Steerable Paraboloid, s6 Copyright © National Academy of Sciences. All rights reserved.
A SoIn Raìlar Sgstem 5z Summarg of Recommen¿htÃnns lor Railìn Telescopes d7 V AUXILIARY INSTÃUMENTS ATID AUTOMATION 58 Auriliaru Instruments 58 Rtd,latìoo Deteeto¡s 59 AuaÃllarg Optìtal Insttuments 60 Atûwsphe c D¿shûbances 67 Recommendt¡tions 62 Autofiwtion 63 lntîod,ucitotu 63 ol Datø 64 Acqu&tÃon ønd, Redua'tÃotl o! Neu; AutoÃtotìc Tnctrønents 65 Deoelopm.ent Infon&tÃor. Stotuge 66 Autonûted. Obsetuatoà as 67 Recotumend,alÃorls 68 VI THE MAGNITUDE OF THE PROGBAM 71 Intîoduction 77 Summary of Recommendations and, Costs 74 Optlcøl Asttunomv 74 Athonomg 75 Rad,lo Aut¡liary lûst )rnetuts and, Automatiþn 75 AÃnual OperatÃag Support 76 oà Cost Esthnøtes and Proiected. Spending Rate 76 Ba.si,s FocìlÃtg Cost Est ñøtes 76 Atunual Opetut¿ng Suppol¿ lot Neto FocilÃtÃes 80 SpendtngRo¿e 83 ExÃstìtul FaailÃtÃes 87 Annral ScÃøntifio Suppoît Ãoà APPENDIX 88 i á .._ Copyright © National Academy of Sciences. All rights reserved.