AMATEUR ASTRONOMY Pubjished Monthly by the American Amateur Astronomical Association Vol. 4-No. 3, March, 1938 Ten Cents Solar Activity and Magnetic Disturbances MAUDE S. WIEGEL, Solar Director Meteoric showers of recent years may transmission. Research into the dcc- be a disappointment to the astronomers, trical state of our upper atmosphere only but the sun is not. The sun is surpass- will answer that question. ing in activity the last maximum and hadio now supplies some knowledge gives promise of the greatest activity of the ion density. By sending a radio since 1870. Bright chromospheric erup- pulse of one or two ten thousandths of tions have been numerous, with the sub- a sec rd. duration upward, the heighth of sequent magnetic storms, sometimes mild, the reflecting level is learned by the sometimes setting up great disturbances lengin of time sequence for the reflection in our atmosphere. io return. One instance, especially interesting, Radio waves travel with the velocity concerns a pilot of an airliner who was of light, 186,000 miles per second, con- flying over South America and receiving sequently the echo time is very short. It radio signals from his base at Lima, Pe- requires only one thousandth of a second ru, and a radio operator at Seattle, for the wave to travel to the height of Washington in touch with vessels at sea; one hundred miles and back. both men found their communications The height at which a radio wave will suddenly cut off. They were receiving be reflected depends upon the characteris- on high frequeñcy and contact was not tics of the wave transmitted. Suppos- reestablished in either case for more than ing a wave is sent directly, upward on a an hour. These two widely spaced points low frequency such as 900 kilocycles ; it were not the only spots to feel the cf- will be reflected when it encounters a fects of the magnetic disturbances. Wor- density of 10,000 electrons per cubic cen- kers at an observatory at Huancayo, Pe- timeter directly above the transmitter. ru, maintained by the Carnegie Insti- If waves are sent out on a higher fre- tution and conducted to record the quency, these waves pass through the strength and direction of the earth's reflecting layer of a lower frequency magnetic field, also the currents in the wave to one higher up. For instance, earth's crust and the electrical state of a wave transmitted on a frequency of the upper atmosphere, noticed at the 9,000 kilocycles encounters 1,000,000 elec- same time that the earth's magnetic trons before it is reflected, and if such field suddenly increased in intensity. It a high density does not exist the waves also shifted its direction a little and the pass into outer space and are lost. Then curi nts in the earth's surface became for each frequency there is a definite unsteady. The disturbance was noticed number of ions which will reflect the throughout the central portion of the wave at normal incidence. A wave is sunlit hemisphere. reflected when it encounters the value While this wide-spread interruption of ion-density which corresponds to that was in progress a brilliant sunspot erup- frequency, so the height of this ion-den- tion was taking place. It was first seen sity is determined. rn a £lydr3gen spectroheliogram taken at In measuring the density of ions in 1:58 p. m. E.S.T. No observations were the upper atmosphere, higher and higher available for an hour preceding this frequencies are used. The time is time. Successive exposures taken at four checked as the echo comes in until a fre- minute intervals show the flocculi de- quency is reached so penetrating that it creasing in brightness until about 2:22 passes all the way through. This is p. ni. E.S.T. when again the region ap- termed the "critical frequency", and peared normal, Did the eruption and the when all frequencies are combined, the Lade-out occur simultaneously? It does heights of layers of various ion-density not seem unreasonable to assume that and the distribution of ionization through- the outburst may have begun about 1:30 out the upper atmosphere, are found. since 28 minutes later it definitely was Earlier methods of measuring the dis- on the decline. It has become a well- tribution of ionization were necessarily known tact that solar and magnetic ef- slow and tedious and the ionosphere may fects are accompanied by radio fade-outs. have undergone changes while a meas- The question now ariç s, what factors urement was in progness. Later meth- are at work in the ionosphere surround- ods were wonderfully improved and now ing the earth that oY!ow the sun to in- four complete records are available each i'luence terrestrial magnetism and radio hour.

PDF compression, OCR, web optimization using a watermarked evaluation copy of CVISION PDFCompressor Page 26 Amateur Astronomy March, 1938 The ionosphere is not a simple struc- cubic centimeter and we have reached ture. Experiments show that two re- the E region. The increase in density gions exist and that the outer one of the at this level is so great that it is usually two under certain conditions divides in- known as "layer.' The ionization now to two regions of ionization; thus at decreases a little, it is believed, and then tunes three distinct regions exist. The increases rapidly until a maximum is region closest to the earth is known as reached somewhat above 130 miles. Here the E region, the next higher the Fi and the density corresponds to about 330,000 the highest, the F2. The E region is electrons per cubic centimeter; this is about 60 miles above the earth. F1 and the F1 region. F2 are about 125 and 180 miles respec- Now as we travel upward the ionisa- tively. In making records of the re- tion remains nearly constant, varying a flected 'waves, it was .noticed that there little at times until we reach the 180 was a displacement of the curve on the mile point, where a sharp increase oc- record similar to the Zeeman effect; this curs. The ion density. here may reach characteristic is said to exist because as much as. 1,000,000 electrons per cubic of the presence of the earth's magnetic centimeter. We have now reached the field in the ionosphere. F2 region. It must be remembered that this dis- Let us suppose that we could travel tribution is for a particular time of day, upward at noon time in some convey- season and year, and may vary under ance that might carry us to the outer- and As certain conditions. The regions E most border of the atmosphere. we F1 are present always, but F2 has a left the earth we would pass through a more transient existence. It is one with thin ion layer of possibly a few thou- F1 except when beneath the direct rays sand ions per cubic. centimeter, due to of the sun-when it seems to bulge while cosmic rays and other sources. At about separating from F1. Its high point, di- 15 to 40 miles we would travel through rectly below the sun becomes F2, and a region of which little is known con- if we move away from the sun in any cerning the ionization from actual ex- direction,, the height of this upper re- periment, but the ionization is thought gion falls until it finally merges with to be relatively low. As we reach the the region below. The separation be- 40 mile height, the density of ionization tween the two regions is scarcely dis- gradually increases and at 60 miles the tinguishable is density increases very suddenly. At less than about 450rn about 65 miles the maximum density cor- Twin Elms Observatory, responds to about 180,000 electrons per Elizabeth, l'a. ifi Section B .W. ROSEI RUGH, Director Editorial Note: Although the February, stars such as o Ceti, Chi Cygni, lt Hy- 1938, issue of Amatexr Astronomy con- drae, R Leonis, R Coronae Borealis and tained a brief review of this book, Dr. R Scuti. After reading this chapter it Merrill's welcome addition to the all too is to be hoped that many amateur tele- scant literature on variable stars in book scope makers will be inspired to start form, the publication committee deemed observing variable stars. If they have it advisable to include the following de- trouble in locating them they may de- tailed review: rive courage from the fact that Sir Wil- The advent of a new book about var- liam Herschel had difficulty at times in iable stars is nearly as exciting to the locating o Ceti. With our modern variable star observing brethren as a AAVSO charts the newest observer will , more especially when it is written find it much easier to locate and follow by one of our "elder brethren." o Ceti through its cycle than the fore- The author of The Natnre of Va'riable most astronomer did in 1780! Stars which can be secured from the When the beginner has done some ac- MacMillan Co., New York, at $2.00, is tual observing he will turn with great an astronomer at the M. )unt Wilson Ob- avidity to Chapter IV which describes servatory and an honorary member of the light curves of cepheids and long the AAVSO. While the book will prove period variable stars. These curves are fascinating reading to any serious mind- very largely based upon AAVSO obser- ed student of the stars, variable star ob- vations as compiled by our beloved re- servers of course will find it of the great- corder Leon Campbell. est value. By this time Chapter II, dealing with Beginners in variable star observ- varieties of variable stars, will take on ing will probably find Chapter III the a new meaning to the enthusiastic tyro most immediately interesting as it gives and he will doubtless review it in the the history of the discovery and early light of his increasing knowledge. The observatio.ns of many interesting variable classification of variable stars into no-

PDF compression, OCR, web optimization using a watermarked evaluation copy of CVISION PDFCompressor March, 1938 Amateui Astronomy Page 27 vae, long period variables ,irregular var- than the sun, while long period variable jables, cepheicls and eclipsing variables stars are red with temperatures of about proposed in 1880 by Director E. C. Pick- 2,800°K which vary in absolute magri- ering of the Harvard College Observa- tude from plus 3 to -1. These three tory, is of historical and sentimental in- types of variable stars lie in the giant terest to the members of the AAVSO star branch of the Itussell diagram and for Plof. Pickering was one of the foun- some possible theories for explaining ders of the AAVSO in 1911 . Although their variations are given. The pulsa- Prof. Pickering's classificatiOn is largely tion theory of Dr. harlow Shapley, im superseded by Ludendorff's classification mediate past-president of the AAVSO is which recognized 10 different types, it is deßcribed in some detail in Chapters VII my understanding that Ludendorff's and VIII as it comes the closest to ex- classification will be superseded in the pìaining the available facts. The thought not too far distant future by newer cias- is voiced that possibly these pulsating sifications based upon the spectra of var- stars, which are large and diffuse, nay iable stars. be stars in the early stages of develop- By the time the new variable star ob- ment in which the force of gravity has server has observed several stars and not yet gained sufficient control to sub- studied the book this far, Chapter V on due the matter in the stars to a steady physical properties will give him some diameter. idea as to what the long period variable The book does not deal with irregular stars he has been dbserving are really variable stars such as the U Geminorum like. With some previous knowledge of and R Coronae Borealis types to any astrophysics, one will have no difficulty extent, but concentrates its attention in interpreting the spectra shown in this principally on periodic variable stars. chapter, in comprehending the Harvard The book is 134 pages in length and classification of stars by their spectra the typography is excellent. It is wed as shown on page 75, or in following the illustrated with diagrams, and numerous table showing the percentage of a star's tables give muci information in a coni- radiation lying in various spectral re- pact form. gions as given on page 83. Those of us however who were taught physics about In our own monthly series of descrip- 1915 when Ganot's Physics and the Bohr tions of diffe.tut types of varaible stars atom were le dernier c'ri and who wish we have reahcd the time to discuss to grasp Chapter V in its entirety might pesiodie variabe stars and it is hoped do well to refer first to pages 536, 606 to start next month. In the meantime and 724 of Russell, Dugan and Stewart's the following article which Arthur L. Astronomy or to Dingle's Modern As- Peck, 1332 N. 14th St., Milwaukee, has trophysics for the energy curves of a kindly written for our readers will black body, the spectral sequence, and serve as an introduction to this fasci- the "Russell diagram." nating subject. Chapter VI, dealing with new or tem- Variables for Maxima Ovservations porary stars, will be of especial interest In reviewing the light curves of xnany to new observers who did not start work of the variables we see th.at the maxi- until the two recent bright novae, DQ mum brightness varies from one period (Nova) Herculis 1934 and Nova Lacer- to another. Also among many of the tae 1936, had already faded. Those of variables the period charges from tiroe us who watched these lonely stars "flame to time. Therefore, it is important that and die," probably have been curious careful observations be made of the stars enough about what we saw to ferret out as they reach their maximum stage. this information for ourselves ere now. Every possible effort should be made to Chapter VII deals with the relative observe the star so as to get the time velocities of variable stars compared with of its greatest brightness. Many of the the sun. it is pointed out that RH Lyrae light curves are very fragmentary, and stars (short period cluster type) and observations are needed at the maxima long period variables move rapidly but phases as well as on the ascending and that cepheids move slowly. A possible descending branches of the . explanation for this is advanced on page Neither should we be content with one 125. or several complete curves, for it takes In Chapter VIII the places occupied the means of many observations and by long period variables, cepheids and many light curves to base any conclu- RH Lyrae stars on the "Russell diagram" sions. are shown. RH Lyrae stars are blue It is thought, that inasmuch as the stars with a temperature of about maxima of nearly all stars listed in the 8,000° K and an absolute magnitudes of accompaning table reach a magnitude zero or about 100 times the sun's bright- well within the light grasp of the smaller ness. Cepheids are yellow stars of about telescope, and as many of the fields are 6,000°K and absolute magnitudes oscil- comparatively easy, the beginner in vari- lating about -2 or 600 times brighter able star observation, especially, might

PDF compression, OCR, web optimization using a watermarked evaluation copy of CVISION PDFCompressor Page 28 Amateur Astronomy March, 1938

easily adopt several of the stars as a column 5, the maximum from Schneller, program. 1938; the last column gives the observed Column three of the accompanying mixamum as published in the Harvard table gives the predicted day of the College Circular 418, 1935. It will be month on which the maximum should oc- noted in this column that those variables cur. That does not necessarily mean having more than one maxima during the that it will or must occur on that date. year reach various degrees of brightness. It undoubtedly will occur within a few Undoubtedly we would find upon inves- days before or after the date given. tigation that the periods from one maxi- However, we can reasonably expect that mum to the next would vary several some will occur on the given date. Ob- days, while the mean period is given on servers should bear this fact in mind the AAVSO charts. In column 4, the when observing. Also the maxima as maximum as given in the AAVSO cata- given on the AAVSO charts must not logue of March 15, 1938 is to be con- be taken as final. sidered the mean of many observations. may be either fainter or In the accompanying table, column i Any maximum the Harvard designation; column brighter than the magnitude as given in gaves 5, the maximum 2, the star; column 3, the predicted date this column. In column of the given month for the maximum.;i from Schneller, 1938, on the other hand column 4, the maximum as given in the gives the brightest observed maximum AAVSO catalogue of March 15, 1937; as reported.

Predicted MAXIMA Date of According According As Maximum to AAVSO to Recently Designation Star in March 1938 Catalogue Schneller Observed 011208 S Psc 18 9.6 8.2 8.3 021024 R Ari 24 8.2 7.3 8.0-8.3 022150 RR Per 21 8.9 7.9 - 022813 U Cet 17 7.5 6.6 7.7-6.8 032335 R Per 2 8.6 7.9 8.3-9.2 035124 T Eri 18 8.3 7.4 - 043274 X Cam 27 8.2 7.3 9.6-8.2-8.8 045514 R Lep 22 7.3 6.0 6.7 050022 T Lep 8 8.4 7.5 8.3 050953 R Aur 12 8.0 6.5 7.7 064030 X Gem 30 8.2 7.7 8.2 102900 S Sex 19 9.0 9.2 9.0 115919 R Corn 20 9.3 7.3 8.5 122803 Y Vir 28 9.4 8.5 8.8 123160 T IlMa 4 8.0 5.5 7.8 1822s0 Y Vir 10 8.6 8.0 9.0 183273 T UMi 2 9.1 8.4 9.3 140113 Z Boo 24 9.3 8.3 9.3 153215 W Lib 27 11.1 9.0 - 154536 X CrB 25 9.0 8.1 9.0 155229 Z CrB 2 10.0 8.9 10.1 160519 W Sco 17 10.8 10.0 - 162807 SS Her 22 8.9 8.0 9.6-8.6 170627 RT Her 15 9.8 8.8 9.6 180531 T Her 22 7.8 6.9 7.8-7.6-7.8 180565 W Dra 25 9.6 8.7 9.0 185032 RX Lyr 19 11.7 11.0 12.5 190941 RU Lyr 12 10.6 9.7 9.9 200812 RU Aqi 30 9.3 7.9 201437b WX Cyg 6 9.4 8.7 - 203816 S Del 26 9.0 8.4 9.0-8.9 210516 Z Cap 5 9.3 8.9 9.9 210903 HR Aqr 21 9.2 8.6 9.7 211614 Z Peg 6 9.3 8.8 9.6 230759 V Cas 22 7.8 7.0 7.8-8.8 233956 Z Cas 9 9.4 8.6 9.9 285350 R Cas 25 7.1 4.8 6.0

PDF compression, OCR, web optimization using a watermarked evaluation copy of CVISION PDFCompressor March, 1938 Amateur Astronomy Page 29 We find that there is only one maxi- stars have been received but Ferdinand mum listed for the star 233956 Z Cas Hartmann writes that the R Coronae for the year 1938. Every effort should Borealis type stars, T Orionis and SU be made to watch this star just before Tauri, have been fairly steady at about and after the predicted date for this the 10th and 9m,5, respectively. The maximum. Referring to Prager, 1934 irregular star Z Cam reached a maxi- we find that this star has been well ob- mum of 10e on 896 while the long period served in the past by members of the star R Agr which has lately been rather AAVSO as well as by other observers. irregular is declining having reached 88 Popular Astronomy vol. 34 p. 142 pub- on 922. The long period star S UMi lishes a short note by Waterfield on the had taded to 88 on 908 and S Ceph was chart of this variable. The ;ar seems at minimum of 111 on 897. T (Jeph s rising having reached 109 on 914. to have a well defined period of 493.0 days maxhnum = 9m.8 (8m.5 S Cyg is reported at minimum on 897 with and the writer found it at an unusually 11.1), minimum = 14".? (14m.0 - 15". low minimum of 123 on 925. By peering 4). Prager gives the spectrum as t7e around the corner of a cloud bank U from Ludendorff. Being an M type star Gem was found at a maximum of 89 on which it should be red, like Betelgeuse and An- 932. Of the five special red stars are under observation with red filters, tares. Also stars of this type show pro- only RS Cyg and R Lep are bright minent calcium lines and lines of other enough to be seen through the filter as metals, in addition there are dark bands the other stars are in the 11-12 mag. the and blue regions of the spec- range at present. DQ (Nova) llerc and in green Nova Lacertae continue to fade, the lat- trum which show obsorption by com- ter having reached 118 on 925. pounds, such titanium oxide. The as The weather has been too cloudy for surface temperature of the M stars the writer to assist Edwin E. Friton, measured with a thermocouple is in the 6542 Smiley Ave., St. Louis, with the neighborhood of 2600°k. Wirde this is AAVSO asteroid work, but it is to be a "cool" star as star tempelatures go, hoped that observers elsewhere have been able to help him. The charts which, he we see that it is much hotter than any prepared for the asteroids visible during earth temperatur.. the winter were well drawn and would Observations Made have been of greater use with clearer Comments on weather. Owing to the poor weather, only a few 3 Yates Boulevard, comments upon the recent variations in Poughkeepsie, N. Y.

AAVSO Nova Program Notes L. E. ARMFIELD Good reports have been received for the months of December and January in spite of the miserable observing conditions which have persistently prevailed throughout the country. We welcome again the renewed activity of Inouye and Swensson, whose names have not appeared recently in these columns. Special men- tion must be made of the excellent reports submitted by Cherryholmes, Schmidt- Cameraite De Vany, Lewis, Inouye of Japan, and Siensson. Waitkus of Pitts- burgh, in addition to reviewing his regions visually, is beginning a photographic patrol of certain areas. The interest being shown by all participants in the search for novae and comets is exceedingly gratifying and their efforts are becoming increasingly valuable to the professional astronomers. In confirmation of the im- portance placed upon the work being done in this program by the novae searchers, a ldtter has been received recently from Dr. Strattin of Gonville & Calus College, Cambridge, England, who wishes to stress before the International Astronomical Union the need for the organization of nova programs throughout the world similar to that of the AAVSO. All participants may well feel proud of their pioneering efforts which have broken the trail for others to follow in increasing the amateur astronomer's scope of helpfulness to the professional members of the science.

PDF compression, OCR, web optimization using a watermarked evaluation copy of CVISION PDFCompressor Page 30 Amateur Astronomy Marcb, 1938 Magnitude of faintest Total star reviewed Nights Observer RegionLocation 9 8 7 6 5 4 3 2 Cherryholmes 7 Columbus (Dec.) ------5 3 1 ------9 83 441 ------9 7 (Jan.) 5 6 ------11 83 83 ------11 70 3 ------3 82 3 ------81 3 ------3 De Vany *1P Davenport (Jan.) 7 ------7 7 ------7 7 ------7 7 ------7 7 ------7 *6P 7 ------7 *7p 7 ------7 Diedrich 43 Milwaukee (Jan.) ------2 ------2 Halbach 49 Milwaukee (Jan.) ------1 6 1 1 9 50 161 1. 9 71 312 0.... 6 Lewis 2 Columbus (Jan.) 4 2 1 ------7 31 231 ------6 42 18 ------4 46 411 ------6 55 .... 1311 ------6 84 ------12 ------3 Inouye 27 Tokyo, Japan (Aug.) ------1 9 3 13 28 (Sept. Nov., Dec.) ------1 9 3 13 84 (Aug.) 5 1 1 2 2 11 35 (Nov., Dec.) . 1 2 1 10 80 (Nov.) ------3 2 5 McNabb, Jr. 8 Acton, Can. (Jan.) ------3 2 ------5 72 ------21 ------3 Moore 54 Milwaukee (Jan.) ------2 11 ------3 16 Perkinson 34 Fresno, Cal. (Jan.) ------4 ------4 101 5 ------5 Rosebrugh 1 Poughkeepsie (Jan.) ------5 2 ------7 52 ------61 ------7 Swensson 25 Evanston, Ill. (Dec.) ------i ...... 1 26 11 ------2 36 231 6 37 231 6 38 221 5 36 (Jan.) ------8 2 1 11 37 821 11 38 821 ii Waitkus 36 Pittsburgh (Jan.) ------i ------i 83 3 ------3 92 i ------i 94 2 ------1... 3 110 1 ------i il Observers 34 different regions, 3400 square degrees of sky reviewed. i Observer 7 photographic regions, approximately 2800 square degrees of sky reviewed. *photographic regions for which numbers have been assigned tentatively. **Twothirds of area reviewed to magnitude 8.5; one-third to magnitude 6.0. The following observers used binos or low powered finders to review their re- gions: Cherryholmes, DeVany (Schmidt Camera), Lewis, Inouye, McNabb, Jr., Moore, Perkinson, Rosebrugh, Swensson and Waitkus. Appreciations are tendered to the following observers for summarizing their observations on the report blanks as described in these columns in the October, 1937, issue of Amateur Astrono'rmy; Cherryholmes, De Vany, Halbach, Rosebrugh, Swensson and Waitkus. 1410 N. Marshall Street, Milwaukee, Wisconsin.

PDF compression, OCR, web optimization using a watermarked evaluation copy of CVISION PDFCompressor Page 34 Amateur Astronomy March, 1938 Announcement The official monthly publication of the American Amateur Astronomical Association Due to the pressure of academic duties, Publication Headquarter. Franklin W. Smith, has tendered his 1312 E. Corti. Place. Milwaukee. Wi.. resignation as director of the AAAA's Affiliated Societies Astronomical Society of Rutherford, N. J. meteor section. The Association sincere- Amateur Astronomers Association of Pittsburgh. ly regrets the loss of Mr. Smith's ser- Pennsylvania. vices as he was exceedingly well quali- Astronomers Guild of Jamestown, New York. fied for the duties entailed. It was dif- Chicago Amateur Astronomical Association. Chi- cago, Ill. ficult to find a capable successor but the Eastbay Astronomical Association, Oakland. Calif. American Amateur Astronomical Asso- The Long Island Astronomical Society, Wantagh. ciation is happy to announce the appoint- N. Y. of Wesley Simpson, 629 Lilac, Louisville Astronomical Society, Eouisville, Ky. ment J. Madison Astronomical Society, Madison, Wis. Webster Groves, Missouri, as director of Metropolitan Astronomical Soqiety, New York. the meteor section, effective March 1, New York. 1938. Milwaukee Astronomical Society, Milwaukee. Wie. New Jersey Astrophysical Society, Woodbridge, N. J. Mr. Simpson is regional director of the Norwalk Astronomical Society, Norwalk, Conn. American Meteor Society's Missouri- Optical Division of the AAA, New York, N. Y. Southern Illinois region and is one of Editorial Staff the outstanding meteor observers in the Miss Elizabeth Wight, Editor country. The Missouri-Southern 11h- Mrs. A. K. Fisher T. lt. Hedengren nois region, under Mr. Simpson's super- E. A. Halbach Earl Needham vision has contributed 37,000 meteor ob- Advisory Editors servations to the American Meteor So- F'rof. Leon Campbell - Variable Stars. ciety during the past seven years. Tru- Prof. Charles P. Olivier - Meteors. George Van Biesbroeck Asteroids, comets. ly, a remarkable achievement. The As- Prof. - sociation expresses its appreciation to and double stars, accepting the respon- Ten cents per copy. $1_00 per year. Mr. Simpson for Membership in AAAA, $1.00 per year sibilities of'the méteor section director- including subscription. ship and extends its sincere best wishes Send all communications to the above address for a long and successful career. Calendar of Events GEORGE DIEDRICH (All Times C. S. T.) MARCH, 1938 the moon at 1:13 A.M. Jupiter 60 i Tue.-New moon at 11:40 P. M. 6' south. Conjunction of Mars and a ,vÇ M.a s,,d fha Uranus at 4:00 P.M. Mars 0° 44' moon at :ai. A. IVI. mars ai south. 29 TuConjuncfion of Saturn and the S Tue.-Superior conjunction of Mer- sun. cury and the sun at 6:00 A. M. 31 Thu.-New moon at 12:52 P. M. 1988 9 Wed.-First quarter at 2:35 A. M. APRIL, 10 Thu.-Opposition of Neptune and the 1 Fri.-Conjunction of Mercury and sun. Neptune 2,714,000,000 miles the moon at 11:51 P.M. Mercury 0° from the earth. Occultation of X9 11' north. Conjunction of Venus Orionis at 11:34:30 P. M. Position and the moon at 5:22 P. M. Venus angle of 112°. Magnitude 4.7. 3° 39' north and of mag. -3.3. moon 11:15 P.M. 2 Sat.-Mercury at greatest elonga- 15 Tue.-Full at Most 17 Thu.-The three planets Venus, Sa- tion east (19° 5'). favorable turn, and Mercury form a right- elongation of this year due to deci- angled isosceles triangle with Venus ded northern declination. at the 90° apex and above (north) 3 Sun-Conjunction of Mars and the of the other two. Saturn is 2° east moon at 1:46 A.M. Mars 0° 42 of Mercury on the imaginary hypo- south. thenuse. Saturn and Mercury wihi 7 Thu.-First quarter at 9:10 A. M. be about 8° above the horizon at Minimum of Algol at 9:80 P. M. sundown, leaving little time for ob- 8 Fri.-Conjunction of Mercury and serving this ususual proximity of Venus at 7:11 A.M. Mercury 3° 52' the planets.* north. 18 Fri.-Minimum of Algol at 8:50 14 Thu.-Full moon at 12:21 P. M. P.M. 15 Fri.-Conjunction of Venus and Ura- 19 Sat.-Conjunction of Mercury and nus at 2:15 P. M. Venus 0° 9' north. Venus at 11:00 P.M. Mercury 1° (Data from the Handbook of the Royal 17' north. Astronoviical Society of Canada.) 21 Mon.-.Sun enters Aries. Spring *Informatjpn from Popalar Astronomy breezes in at 12:43 A.M. Feb. issues 28 Wed.-Last quarter at 7:06 P. M. 3333 W. National Avenue, 28 Mon.-Conjunction of Jupiter and Milwaukee, Wisconsin. PDF compression, OCR, web optimization using a watermarked evaluation copy of CVISION PDFCompressor March, 1938 Amateur Astronomy Pane 35 The Long Island Milwaukee News Notes Astronomical Society M. N. FISHER, Correspondent E. H. CH1tISTMAN, Correspondent Now that spring is coming over the horizon, good observing weather (we At one of our recent meetings, F. K. hope) is finally on its way. The skies Schmid simultaneously made a sugges- in this area were leaden most of the tion and a job for, himself. He suggested winter, although the lack of work at that a library should be organized in the eyepiece was made up by a goodly order to obtain, as a society, looks, peri- amount of paper work and, more im- odicals, magazines and maps .which would portantÏy, by the formation of a new not otherwise be available to individual astronomical unit, The Waukesha Astro- members. nomical society. This bit of co-operative effort is giv- The Milwaukee society and the AAAA ing promise of accomplishing much. It cordially welcome this new group and has created and stimulated an interest in wish the members every success. astronomical literature. Brother Schmid It was on Jan. 31 that 12 men and is the librarian, and a committee of three women met at the Waukesha Y.M.C.A. is covering the task of reviewing, pur- to formulate preliminary plans for the chasing, and collecting likely additions society-to-be. Prof. Vincent Batha, to the small nucleus with which we are chairman of the department of physics starting. at Carroll college, was elected chairman pro tem. L. E Armfield, secretary of The mapping program is reporting the Milwaukee group, explained some of progress. Three enlarging machines the requirements that go along with have been built for the purpose of mak- work in an astronomical unit. ing the final copies of the photographic map. The second demonstration meeting of Seaford, Long Island. the Milwaukee society was held Feb. 3 at the extension division of the Univer- sity of Wisconsin with R. D. Cooke Celestial Globes speaking on occultations, E. A. Halbach on meteors and the methods of handling Through the kind suggestion of an the observations, and with Herbert W. officer of the Chicago Amateur Astrono- Cornell speaking and showing slides on mical Association, the Mid-West Geogra- the recent solar eclipse expeditions. phical Association has courteously of- E. P. Martz, Jr., came up from Chica- fered members of the AAAA an op- go early in February for an all too portunity to obtain a celestial globe. The short visit with Milwaukee members. globes are offered in two styles, "The Speakers during January and Febru- Orion" and "The Leo". The globe it- ary: Halbach, before a church group, on self in either style is nine inches in dia- the immensity of the universe; Armfield, meter. "The Orion" has a heavier base likewise before a church group, on gen- and is equipped with a horizon ring. eral astronomy. Both globes show the brightest stars as 217 N. 2th Street. well as the mythological figures. Quot- Milwaukee, wisconsin. ing the descriptive circular, "the stars are bright yellow on a midnight blue Norwalk Astronomical background with the figures and names in light blue." A 30 page Society booklet, "An Introduction to the Stars' MARY C. HAMILTON, Secretary describing the use of the globe and in- Members were asked to bring items of cluding some elementary astronomy ac- interest to the January meeting. Natu- companies each globe. rally there was duplication, but everyone The regular price for "The Orion" is had so many clippings that each person $5.00 and for "The Leo" is $3.50 plus was allowed only 10 minutes to read postage in each case. However for a them. The subjects included, asteroids, short time only the Mid-West Geographi- meteors, sun spots, the aurora borealis cal Association offers the members of the and the Springfield planetarium. A AAÄA a discount of 35 per cent from lively discussion followed. the regular price. Mr. Martin and Mr. Fleischer told of We suggest that any member desiring their visit to the New Haven Society Mid-West meeting at which Prof. Barton of New a globe send their order to the an on Geographical Association, 608 S. Dear- York gave illustrated lecture his once. trip to Peru last June to view the eclipse. born Street, Chicago, Illinois, at Several guests were present, some of The membership list of the AAAA has whom expect to join the Society. been forwarded to the association to in- 4 Union Park. sure your discount. Norwalk, Connecticut,

PDF compression, OCR, web optimization using a watermarked evaluation copy of CVISION PDFCompressor Page 36 Amateur Astronomy March, 1938 Meteors are believed to set up clouds of Tri State News Notes ionization which retlect waves that pene- AMAThUR ASTßONOMERS' ASSOCIATION trate the Heaviside layer. The moon, on OF PITTSBURGH the other hand, causes a gravitational WILLARD A. MacCALLA, Correspondent pull on the layer, and there is probably Proving that a treasurer can not on- also some ultra-violet reflection from the ly collect and disburse funds with the moon's surface. Following Mr. Kor- greatest o ease, but also can do a line neke's talk a friendly discussion arose job of pinch-hitting when both president between the TN's and the visiting RN's and \ce-president are absent, Joe Goin (radio nuts) as to whether astronomy is admirably conducted our Feb. ii meet- the basis for radio or vice versa. ing. A mirror clinic followed the lecture. At that meeting our group went on "Doctors" Scanlon, Goin, and Scanlon record as favoring a proposal of the prescribed cures for mirrors suffering Pittsburgh city council for creation of a from ingrown toe nails, flat feet, car- non-salaried board to supervise the work bundes and adenoids. Among the "vic- of the bureaus of parks and racreation. tims" were B. E. Knauss' 6-inch mirror, By that change it is believed that we and C. A. Atwell's 12-inch, now in the shall be able to make better use of our "600?' stage. Our old friends, the Opti- parks for the entertainment and instruc- cal Twins (Larry Scanlon and Joe Goin) tion of the public in the subject of a,- are developing a new rapid polishing tr'nomy. It will be remembered that technique, and it is reported that they last summer Fred Garland conducted actually brought a mirror from the 2F weekly classes on astronomy and constel- stage to completion in four hours! lation study at one of the city paiks. Valley View Observatory, The main topic of the February meet- Pittsburgh, Pa. ing was entitled, "What Sun Spots Are Doing to Amateur Radio Transmission." The speaker, Paul B. Korneke, Jr., is a Optical Division of AAA student at the University of Pittsburgh New York and owns and operates statiun W8NEX. Testifying to his activity are cards from ROBERT BLAKEMORE, Correspondeat amateurs all over the world, confirming About 30 members of the Optical Di- two-way communications. Joe Goin re- vision of the AAA met in their work- ports that the ceiling and walls of Mr. shop under the Hayden Planetarium on Korneke's radio room are literally pa- Friday, Jan. 28. Kodachrome movies pered with these cards. and stills of the Peruvian eclipse and According to the speaker, there is an the country en route to the observer's ionized region extending upward from station were shown. At the business about 68 miles above the earth's sur- meeting afterwards, favorable progress face. This is known as the Heaviside was reported on the 21-inch mirror being layer, and is actually composed of live ground in an alcove in the Planetarium or more independent layers, each having theatre. The center of curvature has the property of reflecting radio waves almost been reached. Members agreed of certain high frequencies. The ioniza- to help grind every week-night, assuring tion is caused by the sun's ultra-violet even more rapid progress. The tenjative radiation. This is proved by the partial plans for the observatory which will de-ionization of the Heaviside layer dur- house this young giant were on view. It ing a total eclipse of the sun. is an enviable achievement and should be the Mecca of amateurs and professionals The ability to transmit certain radio but from waves depends upon the height and den- not only from this country layer which in turn abroad. Already several valuable of- sity of the Heaviside the site have been re- varies according to the intensity of the fers of land for radiation. Long radio ceived from Connecticut, New Jersey and sun's ultra-violet Westchester County (part of suburban waves such as used in regular broadcast- City). A start has been ing are affected by magnetic rather than New York magnetic storms made towards having a machine shop, by light conditions, with several members offering sundry having the property of dispersing the it signals. Position tools for metal work. Incidentally, intensity of the radio looks as though the Bell Telephone com- and intensity of the sun's spots cause worlds with earth's magnetic con- pany will investigate new variations in the which to establish communication. No ditions. Thus radio broadcasting ex- have recent- to the ro- less than nine telephone men periences cycles corresponding 'become members and are making cred- tation of the sun spots as well as to the ly 6-inch to spot acti- itable mirrors ranging from familiar 11 year cycle of sun 12.5-inch Cassegrain! vity. Hayden Planetarium. At least two other heavenly bodies be- 81st St. and Central Park W. sides the sun affect radio transmission. New York City.

PDF compression, OCR, web optimization using a watermarked evaluation copy of CVISION PDFCompressor AMATEUR ASTRONOMY Published Monthly by the American Amateur Astronomical Association Vol. 4-No. 3. March, 1938 Ten Cents Prof. William Henry Pickering E. P. MARTZ, Jr., Director, Planetary Section In 1888, with the 13-inch Boyden re- fractor, Pickering obtained some of the earliest successful photographs of the planet Mars, and two years later began extensive visual observations and draw- ings of the planet with the 12-inch Ges'- rish polar telescope and the famous 15- inch refractor in Cambridge. This work seems to have determined much of his future trend. In 1889, after testing a number of sites in the western United States, he established the first Harvard Observa- tory branch on the peak of Mount \\'il- son in southern California, andinstituted work in astronomical photography there with the Boyden telescope It was not until years later that Dr. George Ellery Hale established the present Mount Wil- son Observatory' on the same site. As it was desired to establish a station still W. H. PICKERING further soüth than Mount Wilson, in With Calver Reflector, Jamaica, 1937 1891 Pickering with A. E. Douglass, set On January 17, amid the tropical beau- up the 13-inch refractor and other in- ty of the island of Jamaica in the Brit- struments in the mountains above Are- ish West Indies, there passed away at quipa, Peru, in South America. There, the age of 80 one of the few remaining in the course of extended photographic astronomers of the school of Flammarion, observations, Prof. Pickering discovered Schiaparelli, Lowell. the great whorls of diffuse galactic nebu- William Henry Pickering was born in losity enveloping the whole constellation Boston just before the Civil War of a of Orion. In 1892 he and Douglass dis- well-known Massachusetts family. He covered visually the numerous so-called received the Bachelor of Science degree "lakes" or "oases" on the planet Mars, from the Massachusetts Institute of and also established the existance of Technology in 1879, and taught physics "canali" crossing the dark regions, ce there until 1883. He was early called to "maria", thus proving that the latter nearby Harvard by his brother, Prof. are not "seas", as had previously been Edward C. Pickering, the Director of suspected. Harvard College Observatory, and in After returning to Boston, in the win- 1887 was made assistant professor of ter of 1893, Pickering met Percivâl Low- astronomy there. Throughout this early ell, who, besides being a member of period and in later life, William Picker- the well-known New England mill- ing was an ardent amateur photographer, owning family, was an ardent amateur and did much to develop the application astronomer. Lowell became interested iii of that science to astronomy. Following the work of Schiaparelli and Pickering successful photographs of the great neb- on Mars, and commissioned Pickering ula of Orion with a small camera at- and Douglass to build an observatory for tached to a telescope, he suggested to him in the western United States to be his brother Edward the application of devoted to the study of that planet. photography on a large scale to an as- Flagstaff, Arizona, was chosen as the tronomical survey of the sky. The sug- best site, and in 1894 Pickering and gestion was acted upon, and resulted in Douglass mountdd an 18-inch Brashear the great Harvard photographic survey refractor and a 12-inch Clark on the now containing over 400,000 plates of same polar axis for the first Lowell Ob- both hemispheres. W. H. Pickering de- servatory, and observations of Mars and veloped much of the early technique and Jupiter III were begun. Though Prof. the methods used in his brother's astro- Douglass remained at Lowell Observa- nomical photography and stellar photo- tory for several years, Pickering return- metry. ed to Cambridge to work at Harvard

PDF compression, OCR, web optimization using a watermarked evaluation copy of CVISION PDFCompressor April, 1938 38 Amateur Astronomy George H. Hamilton, who had been ob- observatory. and In 1899 he discovered on Arequipa serving Mars at Lowell Observatory niiìth satellite of Sat- elsewhere, came to Jamaica to work with photograpns the in 1935. urn, ThoeOe. A few years later he re- Prof. Pickering until his death ported a tenth aturnian satellite, but It is impossible to give here an ade- the discovery has flot yet been confirmed. quate discussion of Prof. Pickering's In the same year he undertook the first work in relation to the trans-Neptunian harvard expedition to the island of Ja- planet. Suffice to say that he predicted maica in tne West Indies, to test the positions for it as early as 1907 before astronomical seeing and sky transpar- Lowell's famous paper of 1916, and that CflCY with an excellent 5-inch Alvan when Pluto was discovered by Clyde Clark retractor. He found both very Tombaugh at Flagstaff in 1930, Mount fine, and in 1900-1901 returned to Jamai- Wilson Observatory found it on their ca to spend seven months photographing own plates taken in 1919, close to the the moon with a 135-foot focus 1-inch position predicted at that time by Picker- horizontal telescope. The reaultin liar ing. The earlier plates had not been atlas is published in his book, The Moon, examined for faint enough objects in and in Ha.rvan:t Observatory Annals, 1919, as Pluto turned out to be much Vol. 51. fainter than predicted by either Lowell IlL the small space we have available or Fickering. Though Lowell and Pick- here, it is hopeless to attempt a compre- eling by different methods reached so- hensive summary of the work of Prof. lutions quite close to each other, most W. H. Pickering, but we will note a few modern orbit computers do not feel that of the subjects that occupied his intere.ìt the very early observations of perturba- for the next few years . He early sug- tions of Uranus and Neptune from their gested the rocking-mirror method for "true" paths upon which each based his determining the velocity of meteors, analyses, were sufficiently accurate and which was used with such success by the justifiable data from which to compute recent Harvard meteor expedition to an orbit for a trans-Neptunian planet. northern Arizona. He was the first per- Undoubtedly, the primary credit for the son to develop the theoretical interpre- discovery of Pluto goes to the energetic tation of the rapid changes in the spectra staff of Lowell Observatory, for the long of novae that is today accepted as cor- and successful photographic search which rect, though it is often attributed to other astronomers. He published an ex- In 1935, after several trips abroad and tended investigation of most of the to the States, Prof. Pickering had with known cometary orbits. In a number of him on Jamaica for several months the trips to Alaska, Canada, Hawaii, and the present Lunar Section Director of the Azores, investigations were undertaken AAAA, Walter H. Haas. The next year of volcanic craters and their similarity the writer also had the pleasure of study- to the craters of the moon. ing and observing under Pickering from The year 1911 marks the founding of Jamaica, as described in Amateur Astro- the Jamaica branch of Harvard Observa- nomy and elsewhere.. It is worthy of Prof. Pickering was to spend member of the tory, where in- note here that another much of his later life. The primary AAAA organization, Latimer J. Wilson, strument in use at "Woodlawn", Mande- was also closely associated with Prof. ville, Jamaica, was the excellent 11-inch Pickering for many years in his many photo-visual Clark refractor loaned to to the "Mars Reports." Draper. Con- contributions Harvard by Mrs. Henry W. H. Pickering published over 450 stant visual observations of Mars, the books in the third satellite, Gan- papers and at least two moon, and Jupiter's course of a very prolific life. He was ymede, were continued for many years of scientific so- telescopes. In 1914 a member of a number with it and other cieties, and had several medals and the first of the classical "Mars Reports" upon him in addition by Pickering in Popular awards conferred was published observa- to being an associate of the Royal As- Astronomy. These analyses of of Great Britain. It of the planet by a tronomical Society tions and drawings ran is of interest that, though not primarily number of cooperating observers he observed at least numbers and were continued a solar observer, through 44 six total eclipses of the sun: Colorado in until 1930. Indies in 1886, age of 65 years, 1878, Granada, West In 1924, at the usual in 1889, Chile, South Ameri- was retired by Harvard. He California Pickering at "Wood- ca in 1893, Georgia in 1900, and New decided to retain the estate in 1932. Surely an enviable a private observatory, and in England let lawn" as was re- record for any solar astronomer, 1925, after the Draper telescope efforts were con- he bought a 10-inch alone one whose major turned to Harvard, centrated on the planets! Though his reflector and later a 12.5-inch Calver range, embracing observations of the moon work covered a broad reflector for Prof. astronomical photography, photometry, and Mars. A few years earlier,

PDF compression, OCR, web optimization using a watermarked evaluation copy of CVISION PDFCompressor AprIl, 1938 Amateur Astronomy Page 39

novae, eclipses, meteors, comets, plane- must be established to orient correctly tary and satellite astronomy (planetolo- the projection of the earth's equator on gy), orbit computing, vulcanology, and the disk of the sun. The spots may iow other field's, his influence is felt primari- be marked on the paper, and later, with ly in the study of Mars, the moon, and the aid of the American Ephemeris, the Jupiter III. Though he never seriously correct latitude and longitude cf the considered the basic "theories" of lunar spots determined. and Martian "vegetation", which he was "The paths of the spots across the the first to develop, a more than mere sun's disk usually appear ellipitical,and "working hypotheses", his suggestions are most curved early in March and in formed the primary impetus to the work September. Twice a year, early in June of Percival Lowell and many others. and in December, they become straight It has not been the writer's intention lines. This indicates that the sun's axis to attempt to give in this all-too-brief is not perpendicular to the ecliptic, survey a description of the personal From a great number of careful meas- characteristics of Prof. William H. Pick- urements the astronomers have found ering aside' from those obvious traits that the sun's equator is inclined 7° 1O'.5 that can be inferred from such a long to the ecliptic." and exceedingly prolific life. I will THE IONIZATION OF TIlE leave for another, who is better fitted EARTH'S OUTER ATMOSPHERE than I, the task of relating amusing When the F region subdivides,. as it anecdotes and pleasant sidelights on the does when directly under the sun, form- life of this unusual and inspiring man. ing the two layers, F and F, resemb- However, I cannot help but recall one of ling an immense bulge occupying prob- many cherished afternoons in 1936, when ably about 0.3 of the sunlit hemisphere, we were sitting with our tea on the ver- the upper layer or F region is the most anda at "Woodlawn", watching the ex- highly ionized. As the earth turns, quisite tropical twilight and dusk fall bringing different points on the earth's gently but swiftly over the valley below. surface beneath this bulge, these locali- Deeply moved, I recited aloud that haunt- ties are affected so far as radio reception ing, yet invincibly brave annonymous is concerned, The outer atmosphere re- couplet that marks the resting place of volving with the earth, resumes its ori- John and Phoebe Brashear in the ba'se ginal appearance of one layer, as it of Allegheny Observatory in Pittsburgh. passes from beneath the sun. The Professor chuckled softly, and said earth's tilt of 67 to he liked it too, and he knew who had Owing to the learn the plane of its orbit, the geographical written it. Though I never did beneath the sun vary from him who was the author of these areas directly no more fitting greatly from summer to winter, so that words, there can be divided F region, while quite diotinct final comment on the life of any astro- the de- in the summer at Washington, D,C.. nomer who has given so many years an altit ' of his work as did William where the sun reaches votedly to about 78° at midday, are entirely merged Henry Pickering: in winter for then the sun's highest al- "We have loved the stars too fondly titude is only about 28° at midday. to be fearful of the night. Further study discloses the fact that 26 N. 1mwood Ave., the sun is an important factor in the Oak Park, III. changing characterization of the ioni- sphere. The E region is low in ioniza- Solar Section tion at nights and the F4 region does not WIEGEL, Director appear until after sunrise, when it in- MAUDE S de- forn 'the March issue) creases rapidly until noon and then (Co%tinued creases rapidly. Generally the strength CORRECTION: An incorrect state- to the ar- of ionization is proportionate ment was made inadvertently in my amount of sunlight received. Sesonal ticle "Where Is the Suñ's Equator?", changes, too, are a real factor, ioniza- which appeared in the February 1938 tion in winter being lower than in sum- issue of Amateur Astronomy. Please de- mer, not only in one hemisphere but in lete the first paragraph on page 16 which both. begins with the words, "This accom- in 1932 was a enti- the following: The solar eclipse plished - . . - " and insert cal test, even here in North America. "This accomplished, you have p±ojecte'd, At Washington, D. C., the eclipse was approximately, the earth's equator across ionization of not even total; nevertheless, the disk of the sun and the motion over that place decreaned steadily until the spot parallel to the line is a reflec- nearest totality, later increasing propor- tion of the earth's rotation. The same tionately. principal is observed in photographing line across the The results of tests made at that time the sun, i.e., a horizontal on page 43) space to be occupied by the plate or film (Continued

PDF compression, OCR, web optimization using a watermarked evaluation copy of CVISION PDFCompressor Page 40 Amateur Astronomy April, 1938 Variable Star Section D W. ROSEBR1JGH, Director WAVES Geminorum type stars. In our emphasis on the unusual and dramatic, it should "How looks Appledore in a storm? be that the greater num- I have seen it when its crags seemed not overlooked frantic ber of variable stars seem tolerably reg- Butting against the maddened ular in their variations, and doubtless Atlantic." these stars are of greater importance to James u8ell Lowell Science than the "freaks" such as R Coro- nae and U Geminorum. It is true that circus "freaks" draw more attention than Those who love Nature will be well do the "normal" people watching them, repaid if they read "Ocean Waves and but a study of a "normal" human being Kindred Geophysical Phenomena" by will prove more generally useful in de- Vaughan Cornish, published by the Cam- of man- bridge University Press. The writer's termining the characteristics Lakes kind than a study of the "freaks", and boyhood was spent by the Great the same is doubtless true of variable and the North Atlantic and Mr. Cornish's our descriptions of the mechanism by which stars. We will, therefore, turn at- which tention towards periodic variable stars waves are created, the heights to for the next few articles. These, how- they rise and the speeds at which they var- travel bring to his mind countless happy ever, will not deal with eclipsing with the iable stars, since a star of this type, hours spent in close communion namely Zeta Aurigae, was described very waves. fully in the June-July 1937 issue of On Georgian Bay waves are short and pleas- Amateur Astronomy. choppy. Life can hold no greater Periodic variable stars vary in bright- ure than to breast them in a small sail- far boat on a sunshiny summer day with a ness with considerable regularity, wind blowing out of the west. exceeding the regularity of size and fre- crisp quency of ocean waves. First, such a Artistically waves are at their best when gradually grows one walks along a great beach, such as star is faint, then it the bright, following a curve not unlike the Sable Island or Cape Cod, where we studied waves of well known sine curve which green water and rush madly up the sand, in trigonometry. After reaching a max- leaving strange forms of marine life at imum it gradually fades again to its one's feet. But, of course, waves are starting point and then repeats this per- nost spectacular when they charge upon formance time after time with consider- a ock bound coast. When one watches able regularity both with regard to its such waves the game is to pick out from range of brightness from minimum to the cliff on which one stands the ad- maximum and with regard to the time vancing wave which will dash highest it takes to go through its cycle from faint up on rocks. This big fellow looks good to bright and back to faint again. for 80 feet, but no, 70 feet above sea Several different kinds of periodic level is as high as it reaches. Here variable stars have been clearly recog- comes a whopper, and its topmost spray nized: (a) cluster type (b) cepheids drenches the observers 100 feet above (e) long period. It was formerly the sea, but the next wave, which is ap- thought that these three classes were dis- parently even bigger, is checked by its tinctly separate from each other but it predecessor's backwash and only laps is now believed that they are all of es- angrily some 60 feet up the cliff side sentially the same character and that towards the watchers on its top. they merge into each other. Besides ocean waves there are many Cluster type variable stars are mostly other rhythmic phenomena in nature found in globular clusters. They have such as alternating currents. the seasons been used to determine the distance of of the year, the beating of the human these clusters in a manner that will be heart and the fluctuations of periodic described in the second article of this variable stars which undergo wavelike series. However, a considerable number changes in brightness. It would be a of these stars belong to our general gal- hard matter to decide which is the more actic system. RH Lyrae and RS Bootis beautiful sight. an ocean wave or a are of this type, and cluster type variable variable star field, particularly in the stars are, therefore, frequently referred Milky Way, but fortunately a beneficient to as HR Lyrae type stars and sometimes Nature gives us boti, so let us enjoy as "short period cepheids." Cluster type both stars and waves to the full stars vary through a range of about one kinds of magnitude and their average period is In our studies of different through variable stars we have learned about about half a day from minimum irregular R Coronae Borealis and U maximum to minimum again. However,

PDF compression, OCR, web optimization using a watermarked evaluation copy of CVISION PDFCompressor April, 1938 Amateur Astronomy Page 41 sorne of them take as little as two hours ginning to be used to determine the dis- while others take as long as 22 hours tances of remote galaxies, iii a manner to complete their cycle. Merrill states which will be outlined later in this that in 1935 six hundred and twenty of series. these cluster type variable stars were This brief outline of the different types known. of periodic variable stars and the scien- Cepheid stars are known after their tific uses to which they are put. gives prototype, Delta Cephei, which was dis- an idea of the importance of this subject. covered by Goodricke in 1784. Those of Before we are finished with these stars us who watched Nova Lacertae in 1936 we hope to discuss their physical charac- no doubt often gave Delta Cephei an oc- teristics, their spectra, with comments casional side glance as it lay nearby. on the five special red stars which are If the light curves of cepheids are plott- being studied by. the AAVSO and some ed, they resemble those of the cluster possible theories as to the causes of type variable stars, but it takes them periodic variables. longer, namely 5 or 6 days on the aver- Next month we hope to describe clus- age, to complete their periods, though ter type variable stars and perhaps some take as little as 3 days while oth- cepheids more thoroughly, as a review ers take 32 days to go through their of these stars is a useful ,and perhaps cycles. Their range is about 0.8 magni- necessary, prelude to a more intènsive in and 287 such tude brightness, stars study of long period variable stars to were These known in 1935. stars have which many of us devote much of our been used to establish the scale of our time at the telescope. Milky Way system and to measure the distance to other galaxies. Cepheid Franklin W. Smith, Vineland, N. J., remarks that R Leonis, which is a long stars are sometimes subdivided into: ce- period variable, is now declining after pheids, which rise rapidly to their maxi- reaching a maximum of 6.1 on about ma in a quarter of the time of the whole 8926. U Orionis is also declining after cycle and then fall leisurely to their a rather extended 7 mag. max. Schnell- minima, taking three-fourths of their cy- er's catalog predicted that it would reach cle for this purpose; and geminids, named 5.4 mag. and that R Leonis would reach after Zeta Geminorum, which follow 5.0 mag., which illustrates the uncertain- nearly a pure sine wave and spends ty inherent in these stars. Walter Scott about half the time rising to maximum Houston, instead of submitting observa- and half the time declining to minimum. tions, wants information. "What" he Long period variable stars are those asks "can the Milwaukee observers do to which the members of the AAVSO de- to combat 27 days of clouds in a row?" vote a large portion of their attention, If this is all that is troubling him he as these stars vary enough in brightness should consult Leo J. Scanlon of Pitts- so that their light curves can be well burgh, who is one of our AAVSO coun- determined by eye. Sorne of these stars cill ors. take only 32 days for their cycle, some Surely Scanlon's "cloud-piercing" eye- take as long as 560 days or longer while piece which he showed us at the Spring- the average is about 280 days. Unlike field Telescope Makers' convention at the cluster type and cepheids, long per- Stellafane in 1932 is just the solution, iod stars change several magnitudes in more especially when cluster type vari- brightness. On the average they vary able stars are about to receive our atten- four and a half magnitudes, but Chi tion. This remarkable eyepiece, fitted Cygni, which will soon be visible again into the Stellafane turret telescope, in the northeast, has an extreme varia- showed a brilliant greenish star cluster, tion from 3.5 magnitude at maximum to purporing to be that in Hercules.. Clus- 14.5 at minimum. 2144 of these stars ter type variable stars could be seen were known in 1935 and our old friend flashing into sight and disappearing o Coeti is commonly considered the type with remarkable rapidily, even changing star, though Leon Campbell points out in their locations within the cluster .itelf! Variable Comments, Vol. 1, No. 4, Apri] A rapid calculation based upon the ob- 1925, that these long period variable served phenomena indicated a distance stars may be subvidided into classes by of 0.00 light years for this beautiful the shapes of their light curves in some- object. Yes, it was a spinthariscope! what the same manner that cepheids are subdivided into cepheids and geminids. 74 South Randolph Ave.. These long period variable stars are be- Poughkeepie, N. .

PDF compression, OCR, web optimization using a watermarked evaluation copy of CVISION PDFCompressor April, 1938 Page 4 Amateur Astronomy Variables for Minima Observations L. Peck Arthur stars for niax- March issue of Aatateur AstGonomy we discussed a list of In the very important, and is a program that can be ima observations. While this is there is very by those pcssessing telescopes of only smaller aperture, followed possessing larger telescopes. Many stars are important work to be done by those telescope at hand the descending line of the curve to the limit of the followed on the observer possessing the larger tele- and then lost to view to all those except there over the light curves of many, of the variables we find that scope. On looking find obervations on the ascending is quite a gap from the descending side until we minimum is lost. The AAVSO is very anxious that these side. In this way the should make every effort to gaps be filled. Anyone possessing a large telescope many of the stars on the list as possible. Nor should observe the minima of as are several stars on the the possessor of a smaller telescope lose hope, for there that are well within the range of a three or four inch aperture. list in March issue except that the minima are given The table is the same as the column 2, the of the maxima. Column 1 gives the Harvard designation; instead of the given month for the minimum; column 4, star; column 3, the predicted date 5, the given in AAVSO catalogue of March 15, 1937; column the minimum as gives the observed minimum minimum from Schneller, 1938 and the last column Circular 418, 1935. In column 4, the minimum as given as published in Harvard considered the mean of many in the AAVSO catalogue of March 15, 1937 is to be may be either fainter or brighter than the minimum observations. Any minimum many of the observa- as given in this column. One notices in the last column that simply as less than a given magnitude. While these tions recorded are shown not give the true value observations are perhaps better than none, yet it does Almost all, if not all of this list of stars are visible for the minimum of the star. AAVSO. It would tb's larger telescopes of the members and observers of the in every effort to obtain a true value for each be vieil worth the time spent to make minimum observation. MINIMA APRIL, 1938 MINIMA Recently Predicted AAVSO Observed Star Date Catalogue Schneller Designation (13.9 S Cet 21 14.8 13.9 001909 14.5 (13.9 004047a U Cas 27 15.0 W Cas 19 12.3 11.0 004958 13.1 (12.8 010102 Z Cet 5 13.7 U And 6 14.2 14.0 (13.5 010940 13.3 (13.1 012350 RZ Per 11 18.7 And 17 10.3 11.4 10.7 020448 EV 9.2 9.8 021403 o Cet 25 10.1 U Eri 11 15.4 13.5 - (13.6 034625 14.2 11.3-11.4 042209 R Tau 17 15.0 T Lyn 80 12.0 12.0 081635 12.8 (12.4 084803 S Hya 4 13.0 R Cry 22 14.0 13.0 (13.2 121418 12.8 11.4-114 122582 T CVN 13 12.8 R Hya 29 10.1 (14.0 132422 (13.1 12.5 1425E4 R Cam 2 14.5 R Boo 27 12.8 12.3 12.5-(12.3 143227 14.0 (13.7 150605 Y Lib 2 14.0 X Lib 19 14.6 13.8 1530a0 14.2 (13.1 160221a X Sco 27 14.0 R UMi 8 10.6 10.5 10.5 163172 13.2 14.9-(12.9 164219 ER Oph 26 14.5 18.9 13.8 (12.4 170215 R Oph 1 (12.6-14.0 172809 RU Oph 21 14.2 13.6 4 14.6 14.1 (13.2-13.5 175654 U Dra (12.5 191019 R Sgr 13 18.3 12.'7 7 14.7 14.4 (13.2 200212 SY AqI (14.5 200812 W Cap 9 (14.5 (14.5 Cyg 7 14.5 13.9 13.9 202954 ST 10.9 203422a RU Vul 10 10.8 11.0 Y Aqr 24 15.0 13.6 (13.3 203905 15.0 205627 RE Cap 25 15.0 Vtil 18 13.6 12.6 (12.4-13.6 205923a R (14.1 210504 RSAqr 5 15.1 13.8 15.0 14.2 (14.1 210812 R Eqr 26 (13.9-(14.2 235053 RR Cas 25 13.7 13.7 PDF compression, OCR, web optimization using a watermarked evaluation copy of CVISION PDFCompressor Page 43 April, 1938 Amateur Astronomy

Mira, o Cetj, is predicted to be at minimum on April 25th. Beyond any doubt this is the best known of the long period variables. It has been under observation since 1596. In fact, it is supposed to have been discovered in August of that year when Fabricius, a German clergyman, noticed that it was brighter than Alpha a yellow star of magnitude 2.2. Soon after it was lost to view and, accord- ing to the record, it was not seen again until Fabricius observed it in February 1609. Chapter IV of Merrill's, The Nature of Variable Stars, gives a very good account of the observations made by William Herschel. Because of the star's won- derful sight changes, it was given the name, Mira, meaning, "The Wonderful." It has an average period of 331 days, and in this period its radial velocity, also varies. Joy found that the spectrum of the star varies from M6e to M9e, and predicted the existence of a companion star because of the peculiarities in its spectrum when the star was at minimum brightness. The existence of this com- panion was verified by Aitken with the 36-inch telescope on October 19, 1923. At that time the variable was at minimum brightness (visual magnitude). The com- panion is of tenth magnitude, is bluish-white in color, and is invisible except when Mira is comparatively faint. These two stars certainly form a binary system, for Mira has a of O".239 in 179°.5 (Boss). The more distant com- panions are merely optical. Visually the star varies from a mean maximum of 3m4 to a mean minimum of 9xu.3. Maxima vary from 2m.0 to 4m9, while the minima vary from 8m.6 to lOm.1. Photographical:ly the star varies from a mean of 4m9 to lOm.2. Beyond all doubt this star is one of the most interesting variables on the ' AAVSO observing list. Its minima are well within the light grasp of the smaller telescopes. 1132 N. 14th Street. Milwaukee, Wie. (Continued from page 39) ton of light is proportional to its fre- assures us that sunlight h.aving such a quency and that the higher the frequency be the main source the greater the energy involved in a fun- mador effect must damental quantum 'of light Thus the major effect must be the main source of very high ionization during the daytime, especially far ultra-violet light is of lower regions. energy and the. photons of such light in- of the two volve very high frequencies. When a Since we know that the sun radiates energy upon light of different wave-lengths (in com- photon of this high reacts to them as fre- a molecule, it not only can separate it parison we may refer into its constituent atoms, but it can quencies, for wave-length and frequencies an are directly related), it is not difficult also ionize these atoms by ejecting light electron. Such a. process. is believed to to learn which portion of the sun's of the earth's is active in ionizing these regions of out- occur in the ionization . ultra-violet er atmosphere. The amount of sunlight outer atmosphere by the far that we might observe for each frequen- light of the sun. radiator, Let us examine further the F later cy, if the sun were a perfect which appears only when can be calculated for any assumed tem- or the bulge, of radiation the sun is high over head. This layer perature. The frquency same fashion as the determines the color of light; for ex- does not act in the frequency of perhaps 80 lower regions and is subject to violent ample, a light fluctuations in ionizati'ons within a few thousand million million cycles per sec. from day to appears as a violet, while a much lower hours' time, also changing frequency appears as a red color. High- day. these Seasonal change is also evident, June er and lower frequencies than from December, are invisible to the eye, yet they may be being quite different curve tells while great dissimilarity occurs at each measured. T'he calculated which are wide- us how much energy we should expect of the observing stations ly separated over the earth. from the sun at each frequency. density shows marked The calculated curve and the actual While the ion far changes at the various stations, such curve match very well except in the origin since ultra-violet where the observed light- changes must be of so1ar and none they occur with the period of the solar curve drops suddenly to zero layer here again shows of the higher frequency radiation which day. The F observed at its dissimilarity to Fj layer inasmuch we should expect is actually density at, say, three the earth's surface. We may conclude as it shows the ion the ob- different stations to' be alike for the then that the difference between though the stations served and the calculated curves must same season even in are in different hemispheres. be energy which has been absorbed at the outer atmosphere, and a part Observations of the F layer the earth's bm- time of solar eclipse seems to show little of this energy is available for the separated from sation. variation as it appears law of quantum-physics F'j, however as they merge, some change There is a on page 46) which states that the energy in a pho- (Continued

PDF compression, OCR, web optimization using a watermarked evaluation copy of CVISION PDFCompressor Page 44 Amateur Astronomy April, 1938 The New Meteor Section 01 The AAAA. J. WESLEY SIMPSON. Director The task of co-ordinating the efforts important points at this time, namely, of a large group of observers scattered 1) never observe for less than sixty over a number of states is no easy one consecutive minutes on any date as this and necessitates the formulation of a is the minimum amount of time neces- definite but simple routine. sary for the determination of rates. It is safe to say that among the many 2) record all observations, be they observers scattered throughout the Uni- counts, plots, photographic, telescopic, ted States, there is quite a variety of few or numerous. methods of observing. Each observer A time saving blank, designed for the who advocates his particular type feels purpose of recording the above outlined that it will stress the particular phase information for the records of the AAAA or phases which he believes are the most meteo± section, can be obtained from me important. He will logically feel that in care of the Locksley Observatory, voluminous records covering points and Webster Groves, Mo. A few of these observations not stressed by him, while blanks will be mailed also to those re- having some value, waste time which gional directors of the Ainerican Meteor could otherwise have been spent in de- Society who may desire to distribute termining the results or making additio- them to their observing members togeth- nal observations of the kind which he has er with the regular AMS blanks. stressed. The various types of meteor observa- Obviously, we can not hope to use tions and review of methods used and these many systems of filing and observ- advocated by such an authority as Dr. ing, and it is with this thought in mind Charles P. Olivier will be discussed in that your writer asks of a regular month- a series of short articles. To some, ly report Qf a most elementary nature. these articles will not contain much new These reports are not intended to con- material, but it is good to have the pro- flict in any way with the established cedure of observing and recording ad- routine for submitting reports to the re- vocated by various authorities placed in gional directors of the AMS or to Dr. print for future reference by old and Olivier but are requested only in the new members. spirit of helpfulness so that this section The aims of the meteor section may be may serve more fully the American Me- briefly summarized as follows: To stim- teor Society. Amateur Astronomy reach- ulate and encourage participation in the es many amateur astronomers who are observing programs of and membership not yet members of the AMS and there- in the American Meteor Society to train fore do not have access to AMS publi- new observers and increase the accuracy actions in which meteoric astronomy is of all observers; to publish articles of discussed, consequently, it is the desire lasting interest pertaining to all phases and wish of the AAAA to stimulate of meteoric astronomy, to publish quar- amateur participation in the observing terly, or oftener, if possible, brief sum- programs of the American Meteor So- maries of observations made; to give full ciety through its meteor section and the credit to each contributor for his or her columns of Amateur Astronomy. work, hoping thereby to further stimu- The reports requested by this section late interest and activity, to render all will consist of nothing more than a brief aid possible to the solution of individua] report of the following facts: The date or group problems, and, last but not least, of each observation, using the double to stimulate greater co-operation between date system, i.e., if you observed on the individuals or groups and the American evening of March 15, you would record Meteor Society. the date as March 15-16, 1938, while if The success of this program hinges on you observed on the morning of the 15, three important factors, namely, your the date would be recorded as March 100% whole-hearted co-operation in 14-15, 1938; the time you started and every way possible, good observing wea- ended observing on each date; the total ther to make observing possible, and the number of minutes observed; the total ability of your writer to understand and number of meteors seen during the recor- cope with the problems of the members ded period; a description of the condition as individuals and the section as a whole. of the sky; and remarks describing any obstacles to your vision such as trees, The AAA-A and its various sections houses, street lights, fog, moonlight, et have established a most enviable record cetera. Any additional notes concerning of achievement and it is our obligation unusually bright meteors or any other to become a strong and permanent part the observ- of the association's ideals and achieve- phenomenon observed during fail. ing periods will also be greatly appre- ments. Let us not ciated. It might be well to stress two Lóckeley Observatory. Webster Groves. Mo.-

PDF compression, OCR, web optimization using a watermarked evaluation copy of CVISION PDFCompressor April, 1938 Amateur Astronomy Page 45 AAVSO Nova Program Notes L.. ARMFIELD Names appearing for the first time in these columns are Robert Clyde, Jr., 1362 Putnam Ave., Brooklyn, N. Y., and Don D. Zahner, 142 W. Cedar St., Webster Groves, Mo. We are very happy to welcome them to the ranks of active observers and trust that they will continue the good work. Reports. of exceedingly poor observing weather hav.e been received from all parts of the United States. The value of having a program of this nature on a continental basis was again illus- trated by the excellent report received from Neil McNabb Jr., whose observations reflect the good use he made of the of the clear weather in the Acton, Ontario, Canada, region. The following observations were received for the month of February: Mag. of faintest star reviewed Total Observer Location Region 8 7 6 5 4 3 Nights Clyde, Jr., New York 18 ...... 1 .. 1 2 71 i.... 2 3

Diedrich Milwaukee 43 ------i ... i

Halbach Milwaukee 49 ------i . 1 2 50 ...... 1 1 1 3 71 211... 4 Chicago (Dec.) 18 ------1 1 Karl 14 ------i 1 91 1 ------. i 92 1 ...... i 101 1.... 1 ------2 (Jan) 91 152 ------8 92 152 ------8 101 1 5 2 8

New York 92 4 1 Kirkpatrick 1 1 7 Acton, Can. 8 5 3 ...... 8 McNabb, Jr. 36 8 ...... 8 37 8 ...... 8 38 8 ------8 58 21 3 72 2 4 3 1 10

Milwaukee 54 3 4 Moore 7 Fresno 34 ... 2 1 ...... Perkinson 3 101 .... 2 1 ...... 3

Poughkeepsie 1 .. 3 1 ...... Rosebrugh 4 52 2 2 .. i ... 5

New York (Jan.) 31 i ... 1 1 3 Seely 71 3 ...... 3 (Feb.) 31 ...... 1 1 71 212 5 Evanston 36 1 2 3 Swensson 37 1 2 3 38 12 3 Pittsburgh 110 ...... Waitkus 1 1 Weister.Groves 21 .. 5 Zahner 3 i .... 9 36 .... 213 6 13 observers 23 different regions 2300 square degrees of sky reviewed The following observers, employed binos or low powered finders in reviewing their regions: Karl, Kirkpatrick, McNabb Jr., Moore, Perkinson, Rosebrugh, Swen- sson, Waitkus, and Zahner. Appreciation is again tendered the following persons for summarizing their observations: Moore, Perkinson, Rosebrugh, Waitkus and Zahner. Seely, Swensson, 1410 N. Marshall Street, Milwauke. Wig.

PDF compression, OCR, web optimization using a watermarked evaluation copy of CVISION PDFCompressor Page 46 Amateur Astronomy April, 1938

Calendar of Events Th4 officiai monthly publication of th. GEORGE DIEDEICH American Amateur Astronomical Association Publication H.&dqurt.r. (All Time C.S.T.) Placa. Mliwitukm.. Wh. APRIL, 1938 112 E. Curtli AffU SOCLtk 1. of Mercury and Fri.-Conjunction Atronomica1 Society of Rutherford, N. J. the moon at 11 :51 P. M. Mercury Amateur Astronomers Association of Pittthurgh. o ii' north. Pennsylvania. Conjunction of Venus and the moon Astronomers Guild o Jamestown. New York. Chicago Amateur Astronomical AssociatIon, Chi. 5 : P. M. at 22 ° Venus 3° 39' north and of mag. -3.3 Eastbay Astronomical Association. Oakland. Calif. 2 Sat.-Mercury at greatest elonga- The Long Island Astronomical Society. Wantagh. tion east, 19° 5'. (Most favorable N. Y. Louisville Astronomical Society. Louisville, Ky. elongation of the year due to its Madison Astronomical Society. Madison, Wie. northern declination.) Metropolitan Astronomical Society, New York. 8 Sun.-Conjunction of Mars and the New York. Wie. i A. M. Mars 0° 42' Milwaukee Astronomical Society. Milwaukee, moon at :46 New Jersey Astrophysical Society, Woodbridge, south N. J. '7 Thu.LFirst quarter at 9:10 A. M. Norwalk Aatronlcal Society, Norwalk. Goiw. Division of the AAA, New York. N. Y. Minimum of Algol at 9 : 30 P. M. Optical 8 Fri.-Conjunction of Mercury and Editorial Staff Venus at 7:11 A.M. Mercury 3° 52 MIss Elizabeth Wight. Editor north. Mr.. A. K. Either T. R. Hedengr.n 14 Thu.-Full moon at 12:21 P. M. E. A. Ialbach Earl Needham 15 Fri.-Conjunction of Venus and Ura- Advisory Editore nus at 2 : 15 P.M. Venus O 9' north Prof. Leim Campbell - Variable Stars. of Mer- Prof. Charles P. OlIvier - Meteore. 21 Thu.-Inferior conjunction Prof. George Van Bleebroeck - Asteroids, comets. cury and the sun at 4 : 00 P. M. and double stare. Maximum of the Lyrid shower. cents per copy. $1.00 per year. (AMS shower.) Memberehip In AAAA. $1.00 per year 22 Fri.-Last quarter at 2 : 14 P. M. including subscription. 24 Sun.-Conjunction of Jupiter and the Send all communications to the above address moon at 8:07 P. M. Jupiter 6 23' south. 29 Fri.-New moon at 11 :28 P. M. Phenomena of Jupiter's Satellites MAY, 1938 (In C.S.T.) 1 Sun.-Conjunction of Venus and the moon at i :04 P. M. Venus O 57 APRIL, 1938 north. Day Time Satellite Phenom. Conjunction of Mars and the moon 2 Sat. 4:08 A.M. I S e at 6:38 P. M. Mars 1 27' north. Thu. 3:32 A.M. 1H O D 4 Wed.-Maximum of the Eta Aquarid Sat. 3 :17 A.M. II S e shower.) meteor shower, (AMS Sat. 3 :45 A.M. I S i Uranus in conjunction with the sun,. 14 Thu. 3:12 A.M. III E D P. M. 6 Fri.-First quarter at 3:24 i Sat. 3:00 A.M. II S i in conjunction with Mars I E D 7 Sat.-Venus 00 17 Sun. 2:49 A.M. at 5:00 P. M. Venus only 2' 18 Mon. 3:33 A.M. I T e north. (For comparison-compo- 25 Mon. 3:14 A.M. I T i nents of the double star Epsilon Ly- MAY, 1938 rae are about 4' apart.) 2 Mon. 2:57 A.M. II E D 14 Sat.-Full moon at 2:39 A. M. Total 4 Wed. 1:55 A.M. I T e eclipse of the moon begins at 2:18 4 Wed. 3:04 A.M. II T e A. M. Middle of eclipse at 2:44 7 Sat. 2:33 A.M. IV E T) A.M. Total eclipse ends at 3:09 10 Tue. 3:00 A.M. I E D A.M. 11 Wed. 1:34 A.M. I Ti (Data from the Handbook of the Royal 11 Wed. 2:32 A.M. I S e Aetrononvieal Society of Canada) 11 Wed. 2:53 A.M. II T i 11 Wed 8:02 A.M. II S e (Continued from page 43> 16 Mon. 12:58 A.M. IV T i. in ionization occurs. More eclipse obser- Explation of symbols: varions are needed in both hemispherS E-Eclipe T-Transit before any conclusions can be :reached. S-Shad&W O-Othiitalien The above data were mostly taken from D-Disappearance the. work of I. V. Berkner of the Denart- i-ingress egress Wash- ment of Terrestrial Magnetism; (Data from the Handbook of the Royal ington, D. C., and further discussion of by o- Astronomical Society Canada.> the outar atmosphere as effected Ave.. soon. 3333 West National lar eclipse will appear Milwaukee. Wis. Twin Elms Obeervaory. Elizabeth, 1a.

PDF compression, OCR, web optimization using a watermarked evaluation copy of CVISION PDFCompressor April, 1938 Amateu. Astronomy gage 47 Optical Division of AAA Norwalk Astronomical New York Society R. WALLACE, Correspondent MARY C. RAMILTON, Secretary The practical side of astronomy was With a growing membership-now shown in a lecture by Clinton Hubbell forty, including another employee of the at the meeting leb. 24th. ills subject Lelephone iompany, making ten in all- was, "The Use of Astronomy to lilstab- our group has naa to enlarge its work- lish Boundaries.' He said that civil shop in tCe Hayden i'lanetarium. A engineers now use more scientific meth- more progressive spirit has animated ods than in the past, measuring from a our society to still greater accomplish- certain tree or rock. .Lor the more im- ments than in the past. i'or example, portant boundary lines, such as those we macle a fortunate purchase of some oetween countries, they take their meas- machinery which will be installed soon urements from the stars. He gave as in our shop in the i'ianetarium building. an illustration the dividing line between This machinery includes two lathes, two Alaska and Canada. His lecture was drill presses, and a milling machine. The interesting and initructive and greatly work of grinding the 21-inch mirror with enjoyed by the large number present, a subdiameter tool is progressing, and including one new member and several plans for the mount and observatory visitors. which were recently drawn are receiving careful consideration and some revisions. Miss Swartz gave a brief talk on the The site of the observatory has not yet life and work of Dr. Hale. been decided upon as it is rather prema- 4 Union Park, ture to do so. On Monday, Wednesday, Norwalk, Conti. Friday, and Saturday afternoons our workshops are like a beehive and nearly every workstand is occupied by budding astronomers making mirrors of various sizes in different stages of development. Milwaukee News Notes There is also a real spirit of brother- M. N. EISnER, Correspondent hood, and green members especially are Dr. George A. Parkinson, of the Uni- given individual instruction and advice versity of Wisconsin Extension Division, by more experienced hands. We recently gave one of the regular talks offered the installed a blackboard-a fine idea-on citizens of Milwaukee by the Public Mu- which experienced men can illustrate and was "The answer a member's questions intelligenliy seum on March 2. His subject and dramatically regarding curve of Realm of the Nebulae." mirror, focal lengths, figures, etc. It Four of our members spent an unfor- is our plan that new mem'bers will follow gettably happy day. with the Chicago the footsteps of those of our group who "nuts" on March 13. Messrs. Haibach, have already contributed something tan- Armfield, Hedengren and Prinslow drove gible to the science. down the 90-mile stretch to the Plane- tarium, returning home at the usual On Feb. 25, Dr. Harlocw Shapley, di- hour of 2 A. M. Chicago News Notes rector of the Harvard College Observa- of the month give a more detailed ac- tory, gave an illustrated lecture on "The count of the meeting. Our members Debt of the World to Optical Science." say "Thank you so much" to the Chi- Our members also attended an illustrated cago friends fr their enjoyable day. lecture by Dr. Karelitz, Columbia Uni- Our March meeting had two speakers, versity's consulting engineer on the 200- Messrs. Hedengren and Armfleld. The inch telescope, on "The Mechanical Dif- former read a paper on "The Story of ficulties of the 200-inch Telescope." Vulcan" as a supplement to the article Prof. George Van Biesbroeck of the on that subject which appeared in the Yerkes Observatory on a recent visit to January issue of Amateur Astronomy, the Hayden Planetarium was so im- and he went into interesting as well as pressed with not only our workshops and amusing historical detail. Mr. Armfield's the quality of work members are turn- scholarly paper on "Some Elemental As- ing out, but also with the 21-inch mirror pects of Variable Stars" reviewed char- we are grinding, that he asked whether acteristics of variables and their spec- we had ever considered making a 21-inch tral analysis. Schmidt telescope! Our hats are off to The 13-inch telescope is being install- the Chicago group, for their Schmidt ed at the new observatory which was telescope must have made a big impress- built last summer. It will be ready for ion on Yerkes. use in a few weeks. Optical Division of AAA, 817 No. 28th Street, flayden Planetarium, New York City Milwaukee. Wie:

PDF compression, OCR, web optimization using a watermarked evaluation copy of CVISION PDFCompressor Page.48 Amateur Astronomy April,. 1938 instruments available up to that time, Tri State News Notes iat..ue and longituae had been Invented, Air.imu JtST,ONOMEi,' ASSOCIATION trigonometry developed, the earth's cir- os' fITTSBUXGH cumference fairly accurately determined, ILLAlIJ A acCLLA, Correspondent and stai' catalogs had been compiled. kecent activity in tms area might be the eccentricity of the moon's orbit and characteiieU as "spreading the gospel" precession of the equinoxes were known, ot our fl000y. .Ior instance, Joe (ioin the irrst nova and comet had been dis- gave an iiiustrated talk on the principies covered, and regular planetary observa- ot telescope malung at trie Ligonier high tions were being made. Mr. Roe's talk school a Iew w eeks ago. Following the was so well received that a continuation talk, red at. tiar1anU described many of this historical discussion is being of the celestial oojects which may be planned. seen through home-made instruments. valley View Observatory, IVIr. Garianci, wiio is well known for his Pittsburgh. Pa. series of astronomical lectures at the Wissahickon Nature Cabin last summer, is also scheduled to address the Wilkins- Chicago News Notes burg nigh scnooi students on March 28th. MAX M. FEINSILBE1I, Secretary As a result of the generosity of Dr. The meeting of March 6, 1938 was H. . Kane, Jr., of tne Carnegie, Pa., more than a great success. A very good- ltotary laud, in presenting the boy scouts ly number appeared to hear four astro- of that city witn a small retracting tele- nomical "nuts" from Milwaukee who tra- scope, a nucleus of interest in astronomy veled over icy roads to get here. has been founded in that community. The meeting was begun with a talk In an effort to further that interest by Ed. Martz, one of our own members, which, it is hoped, will lead to the con- who told us how to observe, and what to struction of amateur telescopes and a do with planets. Then the Milwaukee scout observatory, Will Mactialla gave "nuts" took over: T. R. Hedengren, the an illustrate1 talk before the Carnegie "parlor" astronomer, told us how to Rotary Club, describing the pleasures spend an enjoyable stormy evening study- and benents of astronomy. A number of ing the structure of the Milky Wayl other such talks have already been sched- Ed. Halbach, regional director of the uled for the coming month. American Association of Variable Star your humble correspondent wishes to Obser.rers told us the what, why and commend to every amateur astronomer way, of observing meteors; he was fol- the vivid article, "Signs of the Zodiac" lowed by L. E. Armfield, regional direc- by Fred Garland, published in the lieb. tor of the American Meteor Society, with 138 Eopunar Astronomy. Fred has the an instructive talk on variable stars. happy faculty of making a seemingly The last speaker was evidently tired by dry subject really live. In his article he his long and arduous ride because he deftly weaves a tittle yarn around each delegated part of his talk to William of the signs of the zodiac so that the Callum, one of Chicago's active variable reader will easily associate each symbol star observers, who explained the use with its proper constellation. of variable star charts. Inasmuch as Joe Goin's recent promo- C. M. Prinslow, director of the Mil- tion with the Westinghouse Electric and waukee Society's observatory, told us Mfg. Co. will necessitate his being out about its state of construction and the of town much of the time, he feels com- Society's future plans for it, the build- pelled to relinquish his office of treas- ing being practically complete. Many urer of the Pittsburgh AAA. Will Mac- pictures of various stages of construc- Calla has consented to take over the tion were shown, making us believe that books during the remainder of Joe's term. they have been hiding their achievement At our March 11 meeting of the Asso- under a bushel. Best wishes for con- ciation, we had the pleasure of listening tinued success from all of us. to a very competent member of our The meeting was then transferred to group, past president C. B. Roe, on the one of Chicago's leading restaurants, subject of "History of Astronomy." Mr. where we continued to discuss our sub- Roe described the development of astro- jects of mutual interest. Wl,en the din- nomy through the philosophical era be- ner broke up, a few of us under the di- ginning with the construction of Egyp- rection of Ed. Martz, accompanied the tian temples and the earliest Babylonian visitors to view the University of Chi- and Chaidsean writings of 5500 B.C. cago students observatory, which is being The narrative continued with the advent put into first-class condition. of the so-called scientific era in the 5th Evidently qur visitors arrived home century B.C. when Eudoxus built the safe and sound, since we have heard first observatory. From that point, Mr. nothing to the contrary. Many thanks, Roe brought the story up to the time of fellows. Copernicus in the 18th century. 6602 S. Francisco Ave., It is noteworthy that despite the crude Chicago, Ill.

PDF compression, OCR, web optimization using a watermarked evaluation copy of CVISION PDFCompressor