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EDITOR: Judy Butcher Send all articles to- (3i3) 254-1786 45200 Keding; Apt. 102 Utica, MI 48087

The W.A.S.P. is the official publication of the Warren Astronomical Society and is available free to all club members. Requests by other clubs to receive the W.A.S.P. and all other correspondence should be addressed to the editor. Articles should be submitted at least one week prior to the general meeting.

Warren Astronomical Society President: Frank McCullough 254-1786 P.O. Box 474 1st V.P.: Joe Gulino 979-4041 East Detroit, MI 48021 2nd V.P.: Ken Strom 977-9489 Secretary: Ken Kelly 839-7250 Treasurer: Bob Lennox 689-6139 Librarian: John Wetzel 882-6816

'The Warren Astronomical Society is a local, non-profit organization of amateur astronomers. The Society holds meetings on the first and third Thursdays of each month. The meeting locations are as follows:

1st Thursday – Cranbrook Institute of Science 3rd Thursday – Macomb County Community 500 Lone Pine Road College – South Campus Bloomfield Hills, MI B Building, room 209 14500 Twelve Mile Rd. Warren, MI Membership is open to those interested in astronomy and its related fields. Dues are as follows and include a year’s subscription to Sky and Telescope.

Student ...... $21.00 College ...... $25.00 Senior Citizen ...... $25.00 Individual ...... $30.00 Family...... $35.00

Observatory Chairman: Ken Strom 977-9489

Stargate Observatory is owned and operated by the Warren Astronomical Society in conjunction with Rotary International. Located on the grounds of Camp Rotary, features a 12½” club-built Cassegrainian telescope under an aluminum dome. The observatory is open to all club members in accordance with the “Stargate Observatory Code of Conduct”. Lectures are given at Stargate Observatory each weekend. The lecture will be either Friday or Saturday night, depending on the weather and the lecturer's personal schedule. If you cannot lecture on your scheduled weekend, please call the Chairman as early as possible or contact an alternative lecturer. Those wishing to use Stargate must call by 7:00 p.m. on the evening of the observing session. The lecturers for the coming month are:

Sept. 7/8...... Alan Rothenberg ...... 355-5844 Nov. 2/3 ...... Ken Strom ...... 977-9489 Sept. 14/15 .... Ken Strom ...... 977-9489 Nov. 9/10 ...... John Root ...... 464-7908 Sept. 21/22 .... John Root ...... 464-7908 Nov. 16/17 .... Stephen Franks ...... 255-7215 Sept. 28/29 .... Riyad Matti ...... 548-7511 Nov. 23/24 .... Frank McCullough ...... 254-1786

Oct. 5/6 ...... Stephen Franks ...... 255-7215 Oct. 12/13 ..... Frank McCullough ...... 254-1786 Oct. 19/20 ..... Alan Rothenberg ...... 355-5844 Oct. 26/27 ..... Ken Strom ...... 977-9489

Sept 29 - Officers meeting at Frank McCullough home at 4:00p.m. All members are welcome. Any question call Frank: 254-1786

Oct 4 - Meeting at Cranbrook Institute to start at 7:30p.m. Event to be announced.

Oct 6 - Star Party at Cranbrook Institute, to start at 7:00 to 9:00. Bring telescopes to show to spectators. Any question call Cranbrook Institute of Science.

Oct 18 - Meeting at Macomb County Community College Ken Kelly will review the book The Moon, by Pickering, 1903.

K & S MACHINED PRODUCTS Livonia, Georgia

August 10, 1984

The Warren Astronomical Society P. O. Box 474 East Detroit, Michigan 48021

Dear Sirs:

Thank you for sharing May 30, 1984 with us in Livonia, Georgia.

Without your presence and excellent equipment, we would not have had such a wonderful experience.

The picture we received will always remind us of some nice “folks” from East Detroit.

Thanks again for making the ECLIPSE a day to remember.

Sincerely,

Jimmy Kay

CRANBROOK INSTITUTE OF SCIENCE

500 Lone Pine Rd.

Box 801

Bloomfield Hills, MI 48013

(313) 645-3230

Fall Astronomy Programs:

“Space Stations/Space Cities” lecture by Jim Loudon 7:00 pm “Soviet Space Proqram”' 9:00 pm

An animated lecturer who describes himself as “a wandering astronomy popularizer”, Jim Loudon has attracted capacity audiences at previous Cranbrook engagements. He is a dynamic speaker with a gift for putting technologically abstract concepts into tangibly human terms. In these lectures, he will share his excitement about prospects in space exploration. Since this is the autumnal equinox, each lecture will be followed by a “toast” to the new season in the courtyard. Light refreshments will be served.

Jim Loudon, Astronomer Friday, Sept. 21 7:00, 9:00 pm Fee: $5 for each lecture

Star Party

The Institute of Science and Warren Astronomical Society join forces to present an evening of stargazing and natural history interpretation. Travel by private car to Cranbrook Nature Sanctuary, a private 50 acre preserve in Oakland County. The evening will consist of telescope demonstrations presented by members of the Warren Astronomical Society, a discussion of local animal life, and some socializing with cider and donuts around a cozy fire. Participants will be mailed directions prior to the event. The event will be cancelled if there is rain up to 1/2 hour before the beginning of class. Questions on the day of the class may be directed to Melissa Pletcher, 645- 3210.

Saturday, Oct. 6 7:00 - 9:30 pm Fee: $8

Family Astronomy Series

Join us for three programs examining the mysteries of the Universe. In the planetarium, learn about the motions of the sky and changes in latitude. Look through the telescope in the observatory, and learn how telescopes work and methods astronomers use to study the sky. Study the skies with star charts, plots, and outdoor sky observing. Recommended for ages 8 and above, accompanied by adult.

Wednesday, Sept. 26, Oct. 3,10 7:30 - 9:30 pm Fee: $24 children half-price when accompanied by adult

M I N U T E S O F A U G. 1 6, 1 9 8 4 M E E T I N G

THE MEETING WAS CALLED TO ORDER AT 8:10 P.M. BY KEN STROM, VICE PRESIDENT.

KEN KELLY WAS ASKED TO TALK ABOUT THE CAMPOUT AND NOVA VULPECULA – ALTHOUGH THE CAMPOUT WAS NOT WELL ATTENDED, WE DID HAVE A LOT OF ACTIVITIES, AND WE HAD A LOT OF FUN. IN THE DAYTIME WE LOOKED AT THE SUN THRU A C-8 TELESCOPE, LOOKING AT SUNSPOTS. WE ALSO LOOKED THRU A SOLAR PROMINENCE FILTER AND SAW PROMINENCES. WE PLAYED FRISBEE AND VOLLEYBALL WITH ANOTHER GROUP AT THE CAMP. WHEN IT WAS CLOUDY AT NIGHT, WE PLAYED TRIVIAL PURSUIT. EVEN THOUGH THE MOON WAS NEARLY FULL, WE FOUND NOVA VULPECULA IN THE 12 INCH SCOPE. IT WAS CONFIRMED BY SEVERAL PEOPLE. WE ALSO LOOKED AT JUPITER AND THE MOON.

ALAN ROTHENBERG ALSO TALKED ABOUT THE GOLF OUTING AND FUTURE FIELD TRIPS.

FUTURE EVENTS: AUG. 25 - STAR PARTY AT DOUG BOCK'S - 8:00 P.M. SEPT. 6 - CRANBROOK MEETING. SEPT. 20 - MACOMB MEETING. SEPT. 22 - STAR PARTY AT DOUG BOCK'S - 8:00 P.M. SEPT. 29 - OFFICER'S MEETING AT FRANK McCULLOUGH'S - 4:00 P.M. OCT. 6 - STAR PARTY AT CRANBROOK.

THE BUSINESS MEETING ENDED AT 8:35 P.M.

PAUL STRONG GAVE A TALK ON A DEVICE TO CONVERT IMAGES TO DIGITAL FORMAT FOR PROCESSING WITH A MICRO-COMPUTER.

A MOVIE WAS SHOWN ON THE SKYLAB MISSIONS.

RESPECTFULLY SUBMITTED KENNETH KELLY, SECRETARY M E S S I E R O B J E C T S A N D G U I D E S T A R S

BY KEN KELLY

HOW TO USE THE FOLLOWING TWO TABLES:

1. ADJUST YOUR TELESCOPE UNTIL THE POLAR AXIS IS POINTING NEAR POLARIS. IT DOES NOT HAVE TO BE EXACT. POLARIS IS ON THE OPPOSITE SIDE OF THE POLE FROM ARCTURUS AND .8 DEGREES FROM THE POLE. 2. PICK OUT THE OBJECT YOU WANT TO OBSERVE, MAKING SURE IT IS ABOVE THE HORIZON. FIND ITS APPROXIMATE RIGHT ASCENSION AND LOOK IT UP IN THE TABLE OF MESSIER OBJECTS. NOTE THE NUMBERS IN THE GUIDE STAR COLUMNS. 3. THESE NUMBERS ARE THE BRIGHT STAR NUMBERS AND ARE REFERENCED IN THE SECOND TABLE. LOOK UP THE 'BRIGHT' STAR IN THIS TABLE. THIS STAR SHOULD BE VISIBLE TO THE NAKED EYE, SO LOOK FOR IT IN THE SKY. 4. ROTATE YOUR TELESCOPE ON ITS R.A. AND DEC. AXES UNTIL THE STAR IS IN THE CENTER OF YOUR FINDER. ADJUST YOUR ALIGNMENT UNTIL THE STAR IS CENTERED IN THE MAIN SCOPE AS WELL AS THE FINDER. 5. ADJUST YOUR SETTING CIRCLES TO READ THE SAME AS THE R.A. AND DEC. OF THE GUIDE STAR. 6. IF THE NUMBER OF THE DIM GUIDE STAR IS LISTED AS ZERO, THEN THE OBJECT IS NEAR THE BRIGHT STAR, SO ROTATE YOUR TELESCOPE AXES UNTIL THE SETTING CIRCLES READ THE SAME AS THE OBJECT YOU ARE LOOKING FOR. IF THE OBJECT IS NOT IN THE FIELD OF VIEW OF YOUR MAIN EYEPIECE, THEN YOU MAY BE ABLE TO SEE IT IN YOUR FINDER. 7. IF THE DIM STAR IS NOT LISTED AS ZERO, ROTATE YOUR SCOPE IN R.A. AND DEC. UNTIL THE SETTING CIRCLES READ THE SAME AS THE POSITION OF THE DIM STAR. RECHECK YOUR ALIGNMENT AND SETTING CIRCLES ON THE DIM STAR. YOU SHOULD THEN BE ABLE TO GO DIRECTLY TO THE OBJECT AND FIND IT.

THE METHOD OF FINDING THE MESSIER OBJECTS GIVEN ABOVE IS USEFUL FOR THOSE AMATEURS WHO ARE EQUIPPED WITH AND USE SETTING CIRCLES ON THEIR TELESCOPES. WHERE ONE USES SLOW MOTION CONTROLS, STAR-HOPPING IS INCONVENIENT, AND THESE TABLES WILL COME IN HANDY.

THE FIRST TABLE CONTAINS ALL 110 MESSIER OBJECTS IN RIGHT ASCENSION ORDER AT THE 1984.5 EQUINOX. THIS MAKES IT CONVENIENT TO FIND OBJECTS USING SETTING CIRCLES. THE SECOND TABLE CONTAINS ALL THE GUIDE STARS PLUS POLARIS, IN BRIGHT STAR NUMBER ORDER. THESE NUMBERS ARE REFERENCED IN THE 'BRIGHT STAR CATALOGUE' AND ALSO IN THE 'ASTRONOMICAL ALMANAC'.

THE OBJECT CLASSES ARE AS FOLLOWS: DN = DIFFUSE NEBULA. E6 = ELLIPTICAL . GC = GLOBULAR CLUSTER. OC = OPEN CLUSTER. PN = PLANETARY NEBULA. SG = SPIRAL GALAXY.

OTHER NOTES: M1 = SN - SUPERNOVA REMNANT M16 = OC - NEBULA AS WELL AS A . M24 = MW – PATCH - SEE MALLAS, PP 70 - 71. M25 = OC - I.C. 4725 - SECOND INDEX CATALOGUE. M40 = DS - DOUBLE STAR. M82 = IG - IRREGULAR GALAXY. M102 = EG - NGC 5866 IN THE 'ASTRO CARDS'. M110 = EG - NGC 205 - SEE MALLAS, PP 192 - 193.

R E F E R E N C E S

1. ASTRO CARDS. INDEX FINDER CHARTS, BY GEORGE KEPPLE (977). 2. ASTRONOMICAL ALMANAC FOR THE YEAR 1984, U.S. GOVERNMENT PRINTING OFFICE. 3. THE BRIGHT STAR CATALOGUE, BY DORRIT HOFFLEIT, 4TH EDITION (1982). 4. BURNHAM'S CELESTIAL HANDBOOK, BY ROBERT BURNHAM, JR. 2ND EDITION (1978). 5. THE MESSIER ALBUM BY JOHN MALLAS AND EVERED KREH1ER (1978). 6. NORTON'S STAR ATLAS, 16TH EDITION (1973). 7. OBSERVER'S HANDBOOK FOR 1984, ROY BISHOP, EDITOR. 8. SEASONAL STAR CHARTS, HUBBARD SCIENTIFIC CO. (1972). 9. WHAT'S UP, BY DAVID OLSON (1976).

NOTE ON M14: THE DIM GUIDE STAR FOR M14IS NEAR NGC 6366, A 10TH MAGNITUDE GLOBULAR CLUSTER. THIS SHOULD NOT BE CONFUSED WITH M14. ALSO, THE DESIGNATION '47 OPH' GIVEN IN THE ASTRO CARDS IS INCORRECT. THE REAL 47 OPH IS IN (BS 6496). THE DESIGNATION WAS DROPPED IN 1930 WHEN THE BOUNDARIES WERE FINALIZED. UNFORTUNATELY, THE ERROR HAS BEEN REPEATED IN SEVERAL ATLASES.

M E S S I E R 0 B J E C T S ( 1 9 8 4 . 5 )

MES OBJ. RT. ASC. DECLIN. NGC V GUIDE STARS # CLAS CON HR MIN DE6 MIN NUM MA6 BRI6HT DIM NAME

110 EG AND 0 39.5 41 36 205 8.9 337 226 32 EG AND 0 41.9 40 47 221 8.5 337 226 31 SG AND 0 41.9 41 11 224 4.0 337 226 ANDROMEDA 103 OC CAS 1 32.2 60 38 581 7.0 403 0 33 SG TRI 1 33.0 30 35 598 6.0 337 544 PINWHEEL 74 SG PSC 1 35.9 15 42 628 9.6 553 437 76 PN PER 1 41.0 51 29 650 11.5 403 496 BARE.ELL 34 OC PER 2 41.0 42 43 1039 5.7 936 800 77 SG CET 2 41.9 0 -5 1068 9.1 911 779 45 OC TAU 3 46.1 24 4 0 1.6 1165 0 PLEIADES 79 GC LEP 5 23.6 -24 -31 1904 7.4 1829 0 38 OC AUR 5 27.6 35 50 1912 7.0 1791 1773 1 SN TAU 5 33.6 22 0 1952 8.4 1910 0 CRAB 42 DN 5 34.6 -5 -24 1976 4.0 1948 1931 43 DN ORI 5 34.8 -5 -17 1982 9.0 1948 1931 36 OC AUR 5 35.1 34 7 1960 6.0 1791 1843 78 DN ORI 5 46.0 0 3 2068 10.3 1948 0 37 OC AUR 5 51.4 32 32 2099 6.0 1791 1843 35 OC GEN 6 7.9 24 21 2168 5.6 2286 2134 41 OC CMA 6 46.4 -20 -43 2287 5.0 2491 2429 50 OC NON 7 2.5 -8 -19 2323 6.5 2491 2574 47 OC PUP 7 35.9 -14 -28 2422 5.0 2491 2970 46 OC PUP 7 41.1 -14 -47 2437 6.0 2491 2970 93 OC PUP 7 44.0 -23 -50 2447 6.0 2491 3045 48 OC HYA 8 13.0 -5 -45 2548 6.0 2943 3188 44 OC CNC 8 39.2 20 3 2632 3.7 2990 3461 BEEHIVE 67 OC CNC 8 49.6 11 52 2682 6.3 3982 3572 81 SG UMA 9 54.3 69 8 3031 7.0 4301 3771 82 IG UMA 9 54.6 69 45 3034 8.7 4301 3771 95 SG LEO 10 43.1 11 47 3351 9.9 3982 4227 96 SG LEO 10 45.9 11 54 3368 9.4 3982 4227 105 EG LEO 10 47.0 12 40 3379 9.5 3982 4227 108 SG UMA 11 10.6 55 46 3556 10.5 4295 0 97 PN UMA 11 14.0 55 7 3587 11.2 4295 0 OWL 65 SG LEO 11 18.1 13 11 3623 9.6 4534 4359 66 SG LEO 11 19.4 13 5 3627 9.1 4534 4359 109 SG UMA 11 56.8 53 28 3992 10.6 4554 0 98 SG COM 12 13.0 14 59 4192 10.4 4534 4932 99 SG COM 12 18.0 14 30 4254 9.9 4534 4932 106 SG CVN 12 18.2 47 24 4258 9.0 4554 4690 61 SG VIR 12 21.1 4 34 4303 9.8 4534 4695 40 DS UMA 12 21.7 58 11 0 9.0 4660 0 100 SG COM 12 22.1 15 55 4321 9.8 4534 4792 84 EG VIR 12 24.3 12 58 4374 9.7 4534 4932 85 EG COM 12 24.6 18 16 4382 9.5 4534 4792 86 EG VIR 12 25.4 13 2 4406 9.8 4534 4932 49 EG VIR 12 29.0 8 5 4472 8.9 4534 4608 87 EG VIR 12 30.0 12 29 4486 9.3 4534 4932 88 SG COM 12 31.2 14 30 4501 9.8 4534 4792 91 SG COM 12 34.7 14 35 4548 10.3 4534 4932 89 EG VIR 12 34.8 12 39 4552 10.2 4534 4932 90 SG VIR 12 36.1 13 15 4569 9.7 4534 4932 58 SG VIR 12 36.9 11 54 4579 9.9 4534 4932 68 GC HYA 12 38.6 -26 -40 4590 8.0 4786 0 104 SG VIR 12 39.2 -11 -32 4594 8.0 5056 4813 SOMBRERO M E S S I E R 0 B J E C T S ( 1 9 8 4 . 5 )

MES OBJ. RT. ASC. DECLIN. NGC V GUIDE STARS # CLAS CON HR MIN DE6 MIN NUM MA6 BRI6HT DIM NAME

59 EG VIR 12 41.3 11 44 4621 10.2 4534 4932 60 E6 VIR 12 42.9 11 38 4649 9.2 4534 4932 94 SG CVN 12 50.2 41 12 4736 8.1 4915 0 64 SG COM 12 56.0 21 46 4826 8.7 5340 4894 BLACK EYE 53 GC COM 13 12.2 18 15 5024 7.7 5340 4968 63 SG CVN 13 15.1 42 7 5055 8.9 4915 5017 51 SG CVN 13 29.2 47 17 5194 8.4 5191 0 WHIRLPOOL 83 SG HYA 13 36.1 -29 -47 5236 7.6 5056 5287 3 GC CVN 13 41.5 28 28 5272 6.2 5340 5247 101 SG UMA 14 2.7 54 26 5457 8.2 5191 5054 102 EG DRA 15 6.1 55 49 5866 10.5 5191 5744 5 GC SER 15 17.7 2 8 5904 6.0 5854 5694 80 GC SCO 16 16.2 -22 -57 6093 7.2 6134 6084 4 GC SCO 16 22.7 -26 -29 6121 6.1 6134 0 107 GC OPH 16 31.6 -13 -1 6171 9.0 6175 0 13 GC HER 16 41.1 36 29 6205 5.8 6212 6220 HERCULES 12 GC OPH 16 46.4 -1 -56 6218 6.7 6175 6318 10 GC OPH 16 56.3 -4 -5 6254 6.4 6175 6318 62 GC OPH 17 0.3 -30 -6 6266 7.1 6241 0 19 GC OPH 17 1.6 -26 -15 6273 6.9 6134 6453 92 GC HER 17 16.7 43 9 6341 6.3 6536 6588 9 GC OPH 17 18.2 -18 -30 6333 7.6 6378 6445 14 GC OPH 17 36.8 -3 -15 6402 7.8 6603 6493 6 OC SCO 17 39.0 -32 -12 6405 5.5 6527 0 BUTTERFLY 7 OC SCO 17 52.9 -34 -48 6475 5.0 6527 0 23 OC SGR 17 55.9 -19 -1 6494 6.5 6913 6812 20 DN SGR 18 1.0 -23 -2 6514 8.5 6913 6812 TRIFID 8 DN SGR 18 3.7 -24 -20 6523 5.8 6913 6812 21 OC SGR 18 3.7 -22 -30 6531 6.5 6913 6812 24 MW SGR 18 17.2 -18 -26 6603 5.0 6913 6812 16 OC SGR 18 18.0 -13 -47 6611 6.5 6913 6930 EAGLE 18 OC SGR 18 19.0 -17 -8 6613 7.2 6913 6812 17 DN SGR 18 19.9 -16 -11 6618 7.0 6913 6930 OMEGA 28 GC SGR 18 23.6 -24 -52 6626 7.1 6913 0 69 GC SGR 18 30.4 -32 -22 6637 7.8 6879 0 25 OC SGR 18 30.7 -19 -16 4725 6.0 6913 6812 22 GC SGR 18 35.4 -23 -56 6656 5.3 6913 0 70 GC SGR 18 42.2 -32 -19 6681 8.3 6879 0 26 OC SCT 18 44.4 -9 -25 6694 9.1 7557 7020 11 OC SCT 18 50.3 -6 -18 6705 6.5 7557 7063 WILD DUCK 57 PN LYR 18 52.4 33 1 6720 9.0 7001 7106 RING 54 GC SGR 18 54.1 -30 -29 6715 7.7 7194 0 56 GC LYR 19 15.9 30 9 6779 8.3 7417 7178 55 GC SGR 19 39.1 -30 -58 6809 6.1 7194 7623 71 GC SGE 19 53.0 18 44 6838 7.5 7557 7635 27 PN VUL 19 58.9 22 41 6853 8.1 7417 7635 DUMBBELL 75 GC SGR 20 5.2 -21 -58 6864 8.3 7776 7650 29 OC CYG 20 23.4 38 29 6913 7.2 7796 0 72 GC AQR 20 52.6 -12 -36 6981 9.2 7776 7950 73 OC AQR 20 58.3 -12 -42 6994 11.0 7776 7950 15 GC PEG 21 29.3 12 6 7078 6.3 8308 0 39 OC CYG. 21 31.6 48 22 7092 5.0 7924 8252 2 GC AQR 21 32.7 0 -54 7089 6.3 8232 0 30 GC CAP 21 39.5 -23 -16 7099 7.7 8322 8204 52 OC CAS 23 23.5 61 30 7654 7.1 21 8904

G U I D E S T A R S ( 1 9 8 4 . 5 )

STAR B.S. RT. ASC. DECLIN. V # # DESIGNATION HR MIN DEG MIN MAG. NAME

1 21 BETA CAS 0 8.3 59 4 2.27 CAPH 2 226 NU AND 0 49.0 40 60 4.53 3 337 BETA AND 1 8.9 35 32 2.06 MIRACH 4 403 DELTA CAS 1 24.8 60 9 2.68 RUCHBAH 5 424 ALPHA UMI 2 15.9 89 12 2.02 POLARIS 6 437 ETA PSC 1 30.7 15 16 3.62 7 496 PHI PER 1 42.7 50 37 4.07 8 544 ALPHA TRI 1 52.2 29 30 3.41 9 553 BETA ARI 1 53.8 20 44 2.64 SHERATAN 10 779 DELTA CET 2 38.7 0 16 4.07 11 800 14 PER 2 43.1 44 14 5.43 12 911 ALPHA CET 3 1.5 4 2 2.53 MENKAR 13 936 BETA PER 3 7.2 40 54 2.12 ALGOL 14 1165 ETA TAU 3 46.6 24 3 2.87 ALCYONE 15 1773 SIGMA AUR 5 23.6 37 22 4.99 16 1791 BETA TAU 5 25.3 28 36 1.65 EL NATH 17 1829 BETA LEP 5 27.6 -20 -46 2.84 NIHAL 18 1843 CHI AUR 5 31.7 32 11 4.76 19 1910 ZETA TAU 5 36.7 21 8 3.00 20 1931 SIGMA ORI 5 38.0 -2 -36 3.81 21 1948 ZETA ORI 5 40.0 -1 -57 1.77 ALNITAK 22 2134 1 GEM 6 3.2 23 16 4.16 23 2286 MU GEM 6 22.0 22 31 2.88 TEJAT 24 2429 NU-2 CMA 6 36.0 -19 -15 3.95 25 2491 ALPHA CMA 6 44.5 -16 -42 -1.46 SIRIUS 26 2574 THETA CMA 6 53.5 -12 -1 4.07 27 2943 ALPHA CMI 7 38.5 5 16 0.38 PROCYON 28 2970 ALPHA MON 7 40.5 -9 -31 3.93 29 2990 BETA GEM 7 44.4 28 4 1.14 POLLUX 30 3045 XI PUP 7 48.6 -24 -49 3.34 31 3188 ZETA MON 8 7.8 -2 -56 4.34 32 3461 DELTA CNC 8 43.8 18 13 3.94 33 3572 ALPHA CNC 8 57.6 11 55 4.25 34 3771 24 UMA 9 33.1 69 54 4.56 35 3982 ALPHA LEO 10 7.5 12 3 1.35 REGULUS 36 4227 53 LEO 10 48.4 10 38 5.25 37 4295 BETA UMA 11 0.9 56 28 2.37 MERAK 38 4301 ALPHA UMA 11 2.8 61 50 1.79 DUBHE 39 4359 THETA LEO 11 13.4 15 31 3.34 CHORT 40 4534 BETA LEO 11 48.3 14 40 2.14 DENEBOLA 41 4554 GAMMA UMA 11 53.0 53 47 2.44 PHECDA 42 4608 OMICRON VIR 12 4.4 8 49 4.12 43 4660 DELTA UMA 12 14.7 57 7 3.31 MEGREZ 44 4690 3 CVN 12 19.1 49 4 5.29 45 4695 16 VIR 12 19.6 3 24 4.96 46 4786 BETA CRV 12 33.6 -23 -19 2.65 KRAZ 47 4792 24 COM 12 34.4 18 28 5.02 48 4813 CHI VIR 12 38.4 -7 -55 4.66 49 4894 35 COM 12 52.6 21 20 5.10 50 4915 ALPHA-2 CVN 12 55.3 38 24 2.90 COR CAROLI 51 4932 EPSILON VIR 13 1.4 11 3 2.83 VINDEMIATRIX G U I D E S T A R S ( 1 9 8 4 . 5 )

STAR B.S. RT. ASC. DECLIN. V # # DESIGNATION HR MIN DEG MIN MAG. NAME

52 4968 ALPHA-1 CON 13 9.3 17 36 5.22 53 5017 20 CVN 13 16.8 40 39 4.73 54 5054 ZETA UNA 13 23.3 55 0 2.05 MIZAR 55 5056 ALPHA VIR 13 24.4 -11 -5 0.97 SPICA 56 5191 ETA UMA 13 46.9 49 23 1.86 ALKAID 57 5247 9 BOO 13 55.9 27 34 5.18 58 5287 PI HYA 14 5.5 -26 -37 3.27 59 5340 ALPHA BOO 14 15.0 19 16 -0.04 ARCTURUS 60 5694 5 SER 15 18.5 1 50 5.18 61 5744 IOTA DRA 15 24.6 59 1 3.29 ED ASICH 62 5854 ALPHA SER 15 43.5 6 28 2.65 UNUK AL HAY 63 6084 SIGMA SCO 16 20.2 -25 -33 2.89 AL NIYAT 64 6134 ALPHA SCO 16 28.5 -26 -24 0.96 ANTARES 65 6175 ZETA OPH 16 36.3 -10 -32 2.56 66 6212 ZETA HER 16 40.7 31 38 2.81 67 6220 ETA HER 16 42.4 38 57 3.53 68 6241 EPSILON SCO 16 49.2 -34 -16 2.29 69 6318 30 OPH 17 0.2 -4 -12 4.82 70 6378 ETA OPH 17 9.5 -15 -42 2.43 SABIK 71 6445 XI OPH 17 20.1 -21 -6 4.39 72 6453 THETA OPH 17 21.1 -24 -59 3.27 73 6493 27 H. OPH 17 25.8 -5 -4 4.54 74 6527 LAMBDA SCO 17 32.6 -37 -6 1.63 SHAULA 75 6536 BETA DRA 17 30.1 52 19 2.79 RASTABAN 76 6588 IOTA HER 17 39.0 46 1 3.80 77 6603 BETA OPH 17 42.7 4 34 2.77 CHELEB 78 6812 MU SGR 18 12.8 -21 -4 3.86 79 6879 EPSILON SGR 18 23.1 -34 -24 1.85 KAUS AUSTRALIS 80 6913 LAMBDA SGR 18 27.0 -25 -26 2.81 KAUS BOREALIS 81 6930 GAMMA SCT 18 28.3 -14 -35 4.70 82 7001 ALPHA LYR 18 36.4 38 46 0.03 VEGA 83 7020 DELTA SCT 18 41.4 -9 -4 4.72 84 7063 BETA SCT 18 46.4 -4 -46 4.22 85 7106 BETA LYR 18 49.5 33 21 3.45 SHELIAK 86 7178 GAMMA LYR 18 58.4 32 40 3.24 SULAPHAT 87 7194 ZETA SGR 19 1.6 -29 -54 2.60 ASCELLA 88 7417 BETA CYG 19 30.1 27 56 3.08 ALBIREO 89 7557 ALPHA AQL 19 50.0 8 50 0.77 ALTAIR 90 7623 THETA-1 SGR 19 58.7 -35 -19 4.37 91 7635 GAMMA SGE 19 58.1 19 27 3.47 92 7650 62 SGR 20 1.7 -27 -45 4.58 93 7776 BETA CAP 20 20.1 -14 -50 3.08 DABIH 94 7796 GAMMA CYG 20 21.7 40 12 2.20 SADR 95 7924 ALPHA CYG 20 40.9 45 13 1.25 DENEB 96 7950 EPSILON AQR 20 46.8 -9 -33 3.77 97 8204 ZETA CAP 21 25.8 -22 -29 3.74 98 8232 BETA AQR 21 30.7 -5 -38 2.91 SADAL SUND 99 8252 RHO CYG 21 33.4 45 31 4.02 100 8308 EPSILON PEG 21 43.4 9 48 2.39 ENIF 101 8322 DELTA CAP 21 46.2 -16 -12 2.87 DENEB ALGIEDI 102 8904 4 CAS 23 24.1 62 12 4.97

A COMPARISON OF THREE SOLAR FILTERS Richard Hill La Estrella Obs., Resident Observer of Warner & Swasey Observatory, and Recorder for the Assn. of Lunar & Planetary Observers Solar Section

This report compares three solar filters made by two different manufacturers; a glass filter, and a Mylar filter made by Thousand Oaks Optical, and a Mylar filter made by R. Tuthill Inc. The tests were conducted visually using a Celestron 8 with a known wavefront error of less than 1/16 wave and a 12mm eyepiece (160x). All work was done with the sun within one hour of the meridian, on a cloudless day, with seeing of about 1 arc second, excellent transparency and a relative humidity between 20-30%. These tests were made at La Estrella Observatories (privately owned by the author} on August 30, 1984. On this day there was only one sunspot group on the sun (it crossed the central meridian during the UT day) and it consisted of from 20 to 30 umbral spots.

For photographic reasons, the Tuthill filter was supplied in three layers of dark, medium, and thin transparency. When being used visually the dark and medium together provide the best, and most comfortable combination. Those were the only two used in this examination. Through these filters (called simply the Tuthill filter here) the granulation was easily and clearly seen. The limb produced a good sharp edge and some rather faint faculae could be seen on the east limb. In the sunspot group the penumbrae displayed a wealth of detail. Penumbral filaments and grains were distinct. There was much internal, umbral structure, including several detached motes of umbral material. There was a fair amount of scattered light which was most noticeable off the limb of the sun. This is probably unavoidable in the substrate material used in the filter.

Next the Mylar filter made by Thousand Oaks was tested. It was rather taut in its cell and would become more so as the cell heated. The sun was much brighter in this filter. It was so much brighter that additional filtering was needed in order to use the telescope at full aperture. A green filter, neutral filter, and a blue filter were used. The green provided the best filtration and resolution. Granulation could not be seen. At best only a light mottling was detectable and it was on a much larger scale than the granular cells. In the sunspot group the resolution appeared to be no better than 3 arc seconds. No internal detail could be seen in the penumbrae and only the grosser circumferential features could be observed (such as notches or breaks). The umbrae were quite grey displaying poor contrast and they lacked much of the earlier seen detail. There was a soft focus to the limb with very much scattered light beyond as if there were light cirrus clouds in the way. An attempt was made to improve the situation by stopping down to 4 inches and then 2.5 inches. In neither case did it help, it only made the image dimmer, but not sharper or more contrasted.

The glass neutral density filter was then put on the telescope. As the sun moved into the field of view it was nice to see that the fogginess of the scattered light was gone. However, this was soon overshadowed by the inability to achieve sharp focus. There was always a double limb or indistinct limb. When trying to focus on the spot group the problem became obvious. There was strain either in the glass or it was pinched in the cell causing an astigmatic image. In order to locate the problem the telescope was stopped down to 4 inches and the stop was moved across the aperture in different chords. These tests could not be completed. As the instrument was being used a blinding light caused the author to stop observations abruptly. A quick examination showed the problem, and perhaps solved the astigmatism question too. The filter had cracked after only some 10 or 15 minutes of use! This could have spelled a permanent end to solar observing but fortunately the crack had remained a crack and did not shatter. No permanent damage appears to have resulted.

In summary, there seems to be quite a disparity in the quality and price of 'solar filters. There is also a high correlation between the two. Anyone buying the Thousand Oaks filters, either Mylar or glass, would be well advised to leave them out in the sun for a while before buying them. The too tight Mylar could split, and the pinched glass did. However, the Tuthill filter, which was received un- mounted but can be purchased mounted, was loosely mounted in a foam-board cell (according to instructions) and performed admirably. And so, the old adage holds true today, "You get what you pay for…”