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AT TWENTIETH AND NOHTHA,\IPTON STHEET8, EASTON, P~~NNSYL\'.\NI.\ Board of Editors IluGH S. TAYLOI\ \Y. .I. C UNNINGHDI AHTHIJII K. PAHPAHT : AI\T1IlJll V. TOIlOLSKY VOLl ME 45 .JANUAHY 1957 NCMBEH L I SP EC IAL COMMEMORATIVE ISSUE

S t U .II A XI .\" .ll'ION,I/. OfT ICNUS CONTENTS .1. \V. B ,\ nK f :R . P rt' .'f id"~ll l T . T. 1l00 ~~tJo: . Esecnt ioe St rrf'iaru D. H. PRENTJCl-: , T' r r asur er and CONTRIBUTORS ,'j f) Hillho.rse Avenue. New Haven II , Conn.

RfJS .1 NATIONAL UFFI CEli.~ Page 6A \VALL.A~": It. Bnoo..s, Chairmalt N ews and Views DONAl,Ll B. PnF.:-';TIC.;, Director and T rea«­ IUI~r Communications [rom Dr. Barker a11<1 !)G l l illhouse Avenue , New IIa.\'P.Il 11, Con n . Dr, Brode, page'GA Agendas [or the Annual Con uenlions, COM,lfl T T F:lI' ON N ,ITIUN ,I/. I.ECT U UES JII I' S page SA Th e Plutonium Sto ri), page 12.\ F n .\ ~- K ;\'1. C A R P ENTEH, Director Correspondence, page 22A fiG l l illho use Avenue, New Haven II , Con n. THI, .U IER IC A N SCIENTIST is pub ­ Page I lish ed fi ve ti mes a year (J a nu a ry . ~I::Lrclt . JUOf" . Septem ber . Dece mber ) by the Soeiet v H UGH TAYLOR, Th ree Score Y ears of the ~ i~ m a. Xi a t t he :\'Ia ck Printing Co., :!Oth and Northampton S t.s., East on , Pu , and Ten

BU,lRD OF EDITOIlS P. O. Box 703 , Prin cet on , x, ,J. Page 5 ~VI. J o .-\N' c. COOK S O K. Sec r ~ tn.T Y C. J .\NSKY, JR. , The Beqinninqs The A ~If:R ' CAS" Scn:' ·TlsT is e ntere d U ~ of Radio second- cl u -e , matter at t he Easton . Pu. . pos t o tfiee, under the Act of Au,:r;u ~ t 24, 19 12, A physieist-engineer pays tribute to t.he Addit ion al e ru.ry III the N ew l la ve n . Conn. , ofIi(~e . memory of his deceased broth er , Karl post December 9 , 194 :i. .Iansky, who was one of th e founders of EDITORIAL CORRE SPONDENC E an d th e scienc e of . Karl public utf on s for rev iew sho uld b e uddressed Junskv's life exemplifies devotion' to true to P. O. Box 70:l , Princeton, K, J . Tile sub­ mission of manuscripts is welco med but no seient.lfic ideals. How better ca n we pr e­ responaibility for safe keeping ur re turn ca n serve these ideals t.hnn by recording t.hfl h e assu me d . salient facts in such u life'? ADVERTISING C O R RESPONDE"'CE sho uld be addressed to the Ad ve rt.ixing Representut.ive , Mrs, Wi ltlum A. .lumes, Page 1:~ 2 17 Canner St reet, Now Haven , Co nn , GERALD S. H A II'K INS, Th e Deuelop­ C II A NG E OF ADDIlESS sho uld h" .., n t meni of Radio A sirononu) to : S i ~ n l:l. Xi . ij U Hillhouse Avenue , N ew Ha ve n 11. Conn. In artier to avoid th e loss T he scient.ist in charge of the Harvard of nn issue, se nd su ch not.i ce, promptly, Radio Moteor Project reviews the deve lop­ ~ivin~ fu ll name, prev ious address . lo cal or national affi liation 0 8 well a :-o the Hew ment of radio astronomy sinc e its incep­ udd resw. C lai ms for a lost issue m ust b e tion in 1932. The radio sky has been ruude within tiD dn ys of oublicat.ion. mapped, but th e causes of these mysteri­ S UB SCR IPT IO N C O R R E S I' O :-lDENCE ous signals from space ure st ill unknown. s ho u ld b e addressed to : Sig mn Xi , 5t.i H ill­ house Av enue. New Haven" II , C o n n. All chec ks sho u ld be made payable to Si gma X i. Page 28 Arrrrrua K. PARPART, Advancing A nn ual Subscription, $2.00 Frontiers in the Study of R£ology Simtle co py, ;.Or. Fo reig n Sub ... cription, 52 .;30. Co pvria bt.. IQ;jfj, b y T lle Soe iety Page :3-1 of the Hig lna X i. AHTHLR V. T O n OLSKY, Renolution in Pol ymer Chemistry Page 4-l Page 7D .;\H'I'llUH II. SNELL. A Survey of the .J.S. \VEI1\'1<;R, Ph?J.sical A nthro]JoloflY Particles of Phy~ics ... A n A ppraisal The Director of the Division of the The Reader in Physical Anthropology at Oak Ridge National Laboratory and the Oxford and author of Th e Piltdoioa For­ genial author of "Geneva Dairy, August, aery consented, during a visi t to the Inter­ 1955" in the October 195.5 issu e of the national Congress on Anthropology at American Scientist accepts the invitation Philadelphia in September last, to provide of the Editors to review, for t.he 70th An­ the readers of the American Scientist with niversary issue, the present ideas concern­ an appraisal of U10 science of anthropology ing the fundamental particles of physics, at the mid-century mark. Puge 57 Page 88 .JOSEPII R. Rove», Psychology 1:10 G. EVELYN H UTCHINSON, 111al"­ Mid-Twentieth Century ~inalia A young psychologist takes a broad look AIleI' an ab sence of t.wo yea rs from the at th e present and future of his ar ea of pages of the Am erican Scientist, Professor study. Professor Royce has been primarily Hutchinson of Yale U nivers ity accepted working on animal behavior. He ha s car­ th e request of the Editors to contribute ried out research for the government on ce more, for the Sp ecial Anniver sary ranging from submariner aptitude tests to Issue, one of his channing essays on the flight experiences. He is Associate Profes­ state of science, on this occasion some SOl' of Psychology at t.he University of t.hought.s on the problem of evolution. Redlands, California. Page .'l0A Page 74 HVGH TAYLOR AND GUEST RE­ \:Y . .1. CC1\';\"l1\'GIIAM, Automolion. VIEWERS, The Scientists' Bookshelf

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(;ttl>5S by G. O. JONES; :340 pages ; SU.7;") ; John Wilc.,' & Sons 119 pages; S2.00; London : Methuen &: 1956. Co . Ltd., New York : John Wiley & A Folloio-U» Study of War Ne uroses by Sons, 1956. NaUMAN Q. BUll.L and GILIJERT \". Man and the Waters of the U pper Ohio BEEBE' Basin (a symposium); 393 p~ges ; Veterans Administrntion 100 pages; Pymat.uning Laborat ory of lViedieal Monograph, HJ55. Field Biology. Special Publication No. J, Musical .4cousiics (4th edit ion ) by 1956. Mars, the New Frontier: Low ell' s Hypothe­ CHARLES A. CULVER; 30;") pages; 86.00; }lcGmw-Hill Book sis by WELLS ALAN WEBB; 141 pages; Fearon Publishers, IDiiG. Co., 19:)6. The Hardiness of Plants (Vol. VIol' Aqron­ The Concept of Entropy in Communication, onuj] by J. LEVIT'l'; Liuinq Orqanisms and Thermodynamics 278 pages; $7.00; Academic Press, H!:)G. by Y. S. TOULOUKIAN ; Phys'ics and Clcemistru of the Ea rth, Vol . 1, 66 pages; S1.00; Bulletin No . 130, Engi­ edited by L. H. AHRENS, KALEHVO neering Experiment Station, Purdue RAI\"KA~IA, and S. H. R uxconx ; U ni versity, 1956 . 317 pages: 88 .00; :VlcGraw-llill Book California and the Southwest, edited by Co., HJ56. CLH'FORD M . ZIEREH; Landnuirks ill the His/or!! 4 fJ !l!Jiene by 37G pages; $11.25; J ohn Wil ey & Sons, HE:"RY E. Smarus'r: 1!l:)G. 78 pages; 83 .00 ; Oxford u nive rsity Elcmentary Cry stallography by M. J. Press, I !~5G. B UERGlm; l nsects and Spider»: A nook of [(eys with ii28 pages; $8 .75 ; J ohn Wiley & Sons, Biological Notes by C. 1'. FRn:DLANDEU 19:")6. and D. A. PRIEST; 124 pages; 82.7;";; Philosophioal Library, Experimental Physical Chemistry (5th edition) by F. DANIELS,.T. H. MATHEWS, 1956. Ceramics for the Archaeoloqist by AN:"A O. J. W. WILLIAMS, P . BENDER, and R. A. AI~BERTY; SHEPARD; 414 pages; Carnegie Institution of Wash­ 482 pages; 81.>..'50 ; :'dcGraw-Hili Book ington, 195G. Co., 1956. The Psucholoin, of Occupations by A:'oINE nOE ; i Continucd on paye 34.1) 4A THE BEGINNINGS OF RADIO ASTRONOMY*

By C..M. J Al\SKY, .1R.. & Bailey, In c., Wa shin gt on , D . C. KARL Guthe Jansky was born October 22,190,), in what was then the Territory of Oklahoma. At that time his father was Dean of the College of Engineering at th e at l\orman. He was th e third son of Professor Cyril, Methodius Jansky and ~ellie Moreau Jansky. The following facts with respect to his parents ar e of interest. His father, now eighty-six years of age, was born in Ri chland County, , the son of Czech immigrants who cam e to thi s country on a sailing vessel in the early 1860's. Father Jansky sta rte d teaching school at the age of sixteen. He was a teacher throughout his active life, retiring as Professor of Ele ctrical Engineering at the Universi ty of Wisconsin. Karl Jansky's mother's maid en name was "\'ellic Moreau . She was of French and English parentage, her ancestors having come to the United States prior to the Revolutionary War. Although already a graduate of Valpariso University, about 1902 Father Jansky decided that he should have more education. Therefore, he resigned his position as Superintendent of Public Schools in a small Michigan town and entered the University of Michigan. Here he obtained hath graduate and postgradua te degrees in Physics and E lect rical Engineering. By this time th ere were two children in th e family-I, the oldest, and a second son . While at the University of M ichigan, Father Jansky worked under and became a great admirer of Dr. Karl Guthe, a German-American and a member of the faculty of the University of Michigan, In 1904 both Dr. Guthe and our father became members of th e staff of the United States Bureau of Standards at Washington at th e time this institution was founded. In 1905 the family moved from Washington, D .C., to Norman, Oklahoma. When the third 80n WH S born shortl y after reaching Oklahoma Ill) was nam ed after Dr. Karl Guthe, the scientist and teacher whoso guida nce had meant so much to his father. I have gone into Home detail with respect to thi s family history to show that the perseverance with which Karl Guthe Jansky accumula ted scientific data, and the object ivity and creative ingenuity he demon­ st rated in making the fundam ental discovery upon which the Science of Radio Astronomy is bas ed, were not accidental. His family life and ba ckground contributed much. Even his name, Karl Guthe , preserves that of a great physicist and outstanding teacher.

~ P resented at the Nin ery-Fourth Meeting of the American Astronomical Society, The Ohio St.at e Univ ersity , Columbu s, "larch 2:;, H).56 . 5 A~IEnJ(':A.': SCIE XTI S'I' After throe years in Oklahoma the family moved to Madison, Wis­ consin, where Father .Iansky became a member of th e faculty of the University of Wisconsin . Ilcre Karl .Iansky received his public school und his university education. He received his Ba chelor of Science degree in Physics in 1927. He was graduated with honors having been elect ed to membership in Phi Beta Kappa, Phi Kappa Phi, and Phi Sigma Phi. Ni ne years later he received th e Master's degree in Physics from t he sa me insti tution. Karl Jansky was no bookworm. He was an excellent tennis player and an outstanding star on the University of Wisconsin's icc hock ey team. I might abo mention here that later in life, while with Dell Telephone Lab oratories, he becam e th e table tenni s cham pion of Monmouth County, Xe w Jersey, It is unrealistic and, therefore, unsci entific to underestimate th e impact of t he element of chance on human dest iny or as a factor uffect ing man's acquisition of kn owledge conce rning th e universe in which he lives. This in no way detracts from th e credit du e those who t ake the fullest advantage of the opp or tunity chan ce affords, When Karl Jan sky applied for a positi on with Dell Telephone Laboratories in 1I:l28 he was at. first turned down for physical reasons. It so happened t hat ten yea n; pro­ viously I had been a member of th e staff of th e Bell System Laboratories and more recently, while a member of the faculty of the University of , I had spe nt summe rs a t th e Laborat ories. Th erefore, by chance, I happened t o ho in a positi on to argue with members of th e personnel department , with whom I was well acquainted, that Karl Jansky was a good risk. This may have bad some small influence in the Laboratories' decision to hire him . Certainly, Bell Telephone Labora­ to ries and the world of science never had reason to regret this decision. Again t he element of chance enters into the picture. This was the ass ignment of Karl Jansky to the Bell Laboratories' field stat ion at Cliff­ wood, New J ersey, and th e decision of his supervisors to ass ign to him n project inv olving st udies of certain phenomena. All of th ese factors, namely- basic elements of character, inh erent abilities, family environment, scholastic environment, cte ., together with th e decisions of people-the choice of a course of st udy in college, t he choice of a life work, th e choice of an employer, the decision t o em ploy, the assignment to a labora tory branch and to a spec ific project, had a vital influenco upon wha t followed. The stage must be set before the play can begin. The ste ps in Karl .Iansky's work from Hl28 to Hl32 which led to th e discovery which furni shed th e foundation for the Science of Radio Astronomy are fully described by Dr. George C. Sou thworth in his art ide, "The Early H ist ory of Radi o Astronomy," in the Scientific M onthly for Fe brun ry, 105f\. 1 will review th ese briefly because I believe TilE BEGINNINGS OF HADlO AST[WNOMY 7 this history contains many lessons for those of us whose life work is in the field of either pure or applied science, and particularly for students and young people who hope to become scientists. Karl Jansky was given the task of studying certain factors affecting the operation of Bell System transoceanic circuits. It is important to note that this was an applied scientific project with a very practical objective, namely, improvement in transoceanic radio­ telephone service. I used to tell my students in radio-engineering at the University of Minnesota that a radio circuit consists of three parts-(l) a radio trans­ mission installation, (2) a radio receiving installation, and (:~ ) a trans­

.i->:

Karl Gut-he Jansky und his I4 .G meter rotatnble directional mission medium which carries signals from the transmitter to the re­ ceiver. Man can and has throughout the years made remarkable progress in the development and improvement of radio transmitters and re­ ceivers and radio transmitting and receiving antenna systems. However, he can do nothing to modify th e characteristics of the transmission medium. He must use this medium as nature gives it to him . Neverthe­ less, he can by field study and scientific analysis of the results obtain valuable information on what the t.rnnsmission medium does to his radio signal and the types of static, noise, etc., affecting his use of it. In 1928 Karl Jansky began his studies of the radio transmission medium and specifically of static and interference noises. While some 8 A;\fEIUCAN SCIEN'I'IS'I' of his work was done on long of the order of 4000 meters, of particular concern to radio astronomy are his studies on 14.6 meters (20.53 megacycles). These required instrumentation and it is important to note that in the late 1920's and early 1930's adequate instrumentation for his project, and particularly for wavelengths as short as 14.6 meters, involved many new and unsolved problems. Every scientific worker makes use of the results obtained by others who have gone before and of advice and help from co-workers. Karl Jansky had much help from the results.of past research work and from other engineers in Bell Telephone Laboratories. This in no way detracts from e,he credit due him for his scientific discovery. Rather, it extends credit to those who by advice and counsel contributed to the final result. About March 1929, Karl Jansky began the design of a 14.6 meter rotatable, directional antenna system and the development of the associated receiving apparatus. Construction of the antenna was started in August 1929. At the same time he was still working on the study of static on long wavelengths. In 1930, the Laboratories' field station with which he was connected was moved from Cliffwood to Holmdel, New Jersey. Therefore, it was not until the fall of 1930 that the 14.6 meter rotatable antenna and its associated receiving and recording equipment were in good working order. Next came the long period of time devoted to the unimpressive, prosaic, and laborious taking of data, that is, data on the characteristics and intensity of static re­ ceived on 14.6 meters as a function of two variables-(a) time, and (b) direction. I wish to dwell for a moment on the subject of data taking. It is one thing to sit at a desk and on the basis of information and data gathered by others hypothesize with respect to the laws of nature. It is another to design, develop, and build apparatus and equipment and then to embark upon a long, tedious program of taking accurate, dependable data on what actually takes place. There are some who look upon data taking as beneath the dignity of true scientists preferring to leave this detail work to assistants. I do not wish to disparage the value of theory and speculation as necessary elements in any scientific study but rather to emphasize that Karl Jansky's work demonstrates how essential is the accumulation of adequate, accurate data. This is as true with respect to studies of radio propagation phenomena as it is in astronomy. A fair share of my life as a radio engineer has been devoted to the field study of the radio propagation medium. I subscribe to a philosophy of approach with respect to work in this field of science. If an objective scientist takes sufficient data and then without the prejudice of pre­ conceived theories or hypotheses analyzes the results, somehow nature's laws will become almost self-evident. The scientist's problem is to rec­ ognize basic facts even though they are obscured by a wealth of ex­ THE BEGINNINGS OF RADIO ASTRONOMY 9 traneous material, and then to apply creative imagination In their interpretation. This Karl Jansky did. In a paper titled, "Directional Studies of Atmospherics at High Frequencies," presented at Washington, D.C., in April 1932 before the International Scientific Radio Union, Karl .Iansky described his equip­ ment and classified the types of static he was receiving on 14.6 meters into three distinct groups. The first group he described as static from local thunderstorms, and the second as static from thunderstorms some distance away. Then he stated, "The third group is composed of a very steady hiss static the origin of which Is not yet known." While he specu­ lated on the possible source of this new type of static, it is important to note his comment that "the data as yet only cover observations taken over a few months and more observations are necessary before any hard and fast deductions can be drawn." I am not concerned here with specific dates. They are all a matter of record . What is important is the long period of time devoted to the accumulation of data on static as received on 14.6 meters as a function of time and direction and the creative interpretation of this factual evi­ dence. Dr. J. H. Dellinger, a prominent authority on radio propagation, at one time stated in effect that no one is interested merely in data but in what the data show. Before the \Vashington meeting of the International Scientific Radio Union held in April 1933, Karl Jansky presented his paper in which he stated his conclusion as to what the data showed. The title of this paper is, "E lectrical Disturbances Apparently of Extra­ terrestrial Origin." Note the use of the word "apparently." This illus­ trates a modesty which I am sure astronomers, and all true scientists both understand and appreciate. In his paper Karl Jansky set forth with reasonable accuracy, con­ sidering the limitations of his antenna, the point of origin of the extra­ terrestrial hiss static he was receiving. I will quote from the paper:

"In conclusion, data have been presented which show the existence of electro­ magnetic waves in the earth's atmosphere which apparently como from a direction that is fixed in space. The data obtained giv e for the coordinates of this direction a right ascension of 18 hours and a declination of -10 degrees. " T he experiments which are th e subject. of t.his paper were performed at Holmdel, N..1 . (Latitude 40 ° 22 ' N and Longitude 74° 10' W ) during the year J!l32."

:Xow, I am all electronic engineer and uot an ustronomcr. My com­ ments must he taken with this limitation in mind. I look upon Karl Jansky's paper, "Electrical Disturbances Apparently of Extraterrestrial Origin ," as a classic. It is ill effect a wedding ceremony. It weds the science of astronomy and the science of radio and electronic engineering. It ties these sciences together by inseparable bonds. :'I'Iy collegia te studies were in a field of pure science, namely, physics. Then I became a teacher of an applied science, namely, radio and elec­ 10 ,u m mCAX SC lE"TIST tricul engineerin g. In Illy teachin g days when I was perhaps more willing to generalize than now, I used to define a pure scientist as one who if he saw a practical application of what he was doing somehow felt con­ taminated by comm ercialism and an applied scientist, as one who if he could not see a practical application of his work would lose interest. Is it not true th at there exists no definitive boun dary between pure and applied science'! The discovery of ext raterrestrial noise came as a result of a resear ch pro gram originally directed to a very practical end. T oday, radio astronomy is making possible the }levelopment of radio sextants which will ena ble th e navigators of ships and aircraft to take celesti al bearings without regard to visibility conditions. What better illustration is th ere th at a practical scientific study may lead to discoveries in the field of pure science, or that research in pure science may yield highly pra ctical results'! Nn.turally, I had at least a limited appreciati on of what was going on in Karl J ansky 's mind in the early 1030's when he was gathering large amounts of data and also t rying to figure wha t the data meant. I remem­ her well when he started the study of th e basic principles of astronomy, a field of science in which he had had no previous training. He felt this necessary if he were to interpret t he mass of factual inf ormation he was collecting, I lind his descrip tion of as t ronomical coordinates as lucid as anything on th e subject I have read elsewhere . Very pr obably this is becau se my training and experience had been in th e sa me field of science as was his, namely, physics and electronic engineering. I recall am ong other th ings that after Karl Jansky concluded that his hiss static carne from th e cen ter of the he went back and tried correlating the data he had taken some tim e previously. At. first it looked as though in some instances no correlat ion existed. Then suddenly he reali zed th a t some of these early data had been record ed using daylight saying tim e. Wh en he applied th e correction, he found these previous da ta tend ed still further to support his discovery. Karl Guthe Jansky died in Red Bank, New Jersey , in F ebruary 1!)50 at th e age of forty-four. In the trying period th at followed his death I told th e members of his family that his contribution to basic science was such that. th e full value of his discovery would not be recognized for at least half a century. How wrong can a man he! Here just six yea rs later I find mys elf before a group of astronomers, physic ists, and radi o engineers far more competent tha n I , viewing with amazement th e prog­ ress which has taken place in recent years in a new bran ch of astronomy based upon a scientific discov ery made by a man I am proud to say was my bro th er. In th e atmosphere of in ternati onal tension th at exists t oday th ere ar e those who view with alarm all scientific effort, whether pure or applied, because they fear th at the destructive pot entiali ties of modern irnplc­ TIl}<; BEGJNXIXGS OF HADIO ASTHOXO~IY 11 men 1.:; of warfare developed by scientists are so great that they may lead to the extermination of civilization. I suggest we should view man's search for scientific knowledge in a different light. The frontiers of radio astronomy are being pushed back hy the efforts of work ers in many nations-v-Grcat Britain, The Netherlands, Australia, th e United States, Callada, Ru esia, France, Japan, Norway, Sweden, etc . As work ers in one country develop new instrumentation and acquire new kn owledge, that information is conveyed to fellow work ers in ot he r countries. Meetings held in one nation ar e att, end ed by scient ists from ot hers. The emphasis is not primarily on competition but upon mu tual under­ standing and cooperative effort directed to wards a common objec tive-­ the acqui siti on of more and more knowlcdge of th e uni verse in wh ich we live. Have I not described a mode of living and a philosoph y of life which must be understood and followed by mankind generally if th ere is eve r to come a day when there will be eternal peace between nations'? Therefore, is it not appropriate to say tha I, among th e most effective apo stles for peace are th escicnt.ists who not only by their discoveri es mak e life more worthwhile but who also through the ir way of life demon­ strato how th e peoples of different nations should coopera te with one another and live together on this planet, a planet which somehow seems to grow smaller and smaller as our knowledge of th o universe is enlarged'? Progress in science is based 011 fac t but scientists ar e :I:; human as anyone else-lawyers, politicians, 01' business men. There exists in each of us to a more or less extent, a tendency to be somewha t. envious of the superior accomplishments of others, How ever, th ere seems to be some­ thing which affects the viewpoint of those who have dedicated th eir lives to the search for scientific knowledge, which more than counteracts this tendency. I do not know just how to explain thi s except to state that to be effective the search for truth must he obj ective and if one is objective then one is quick to give credit where credit is du e. In my limited and admittedly superficial study of astronomy and particularly radio astronomy, nothing has moved me more than the readiness with which astronomers and others have not only extended credit to Karl Jansky for his discovery but also have given full credit to other early workers in radio astronomy and to each othe r. 1 not e that already there is coming into common use a basic unit of power density named after Karl Guthe Jansky. Karl Jansky gave us our first hrief look at interst ellar space th rough a new and previ ously unknown wind ow in th e electromagn etic spectrum. \\'e now know that thi s new window is from 50 to 100 tim es wider than th e opti cal window previously available. He pull ed ba ck th e curtain only a. very little but it was enough to inspire others to attack th e 12 AMERICAN SCIENTIST problems of instrumentation and data gathering so necessary to take advantage of the opportunity now available. In remembering Karl Jansky, his work and his discovery, we should remember that his philosophy of life was that of a true scientist-per­ severence in the accumulation of data, objectivity in analysis, modesty, credit to others for their contributions, and a willingness to leave the ultimate evaluation of one's work to the future.