The Journal Of The Association Of Lunar And Planetary Observers C::lte Strolling Astronomer

11111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111 Volume 29, Numbers 3-4 Published December, 1981

Another suggestive Earth-based, pre-Voyager view ofthe curious dusky bands in the rings of ? Drawing by Toshihiko Osawa in Japan on December 26, 1972 at 13 hrs., 45 mins., Universal Time. 8-inch reflector, 286X. Seeing 4 to 7, rather poor to fairly good. Transparency 4.5 (clear). Simply inverted view with south at the top. B (tilt to Earth) = -26.4 degrees. B' (tilt to ) = -26.6 degrees. Opposition on December 9, 1972. See text on pages 87 and 88. !1111111111111111111111111111111111111111111111=- THE STROLLING ASTRONOMER - Box 3AZ - University Park, New Mexico - 88003 - Res1dence telephone 522·4213 (Area Code 505) - in Las Cruces, New Mexico - Founded In 1947 INTIDSISSUE mE APPARITION OF BRADFIELD 1979 X, by Stephen J. O'Meara and Daniel W. E. Green ...... pg. 45

WHAT IS NEW ON MARS-MARTIAN 1979-1980 APPARITION REPORT ll (Concluded), by C. F. Capen and D. C. Parker ...... pg. 51 mE 1981 A.L.P.O. BUSINESS MEETING, by Phillip W. Budine and Julius L. Benton, Jr...... pg. 60

AMATEURS AMONG THE , by J. U. Gunter ...... •...... pg. 61 mE MINOR PLANETS: AS INTERESTING AS EVER, by Alain Porter ...... pg. 64

COMET WEST 1976 VI: OBSERVATIONS OF THE OF 1976, by Derek W allentinsen ...... pg. 69

BOOK REVIEWS ...... •...... pg. 79

NEW BOOKS RECEIVED, by J. Russell Smith and Charles S. Morris ...... • pg. 83

THE A.L.P.O. AT ASTROCON '81, by Don Parker and Jeff Beish ...... pg. 83

ANNOUNCEMENTS ...... •...... pg. 85

OBSERVATIONS AND COMMENTS ...... •...... pg. 87 THE APPARITION OF COMET BRADFIELD 1979 !

By: Stephen J. O'Meara and Daniel W. E. Green, A.L.P.O. Section

Abstract Visual photometric observations of Comet Bradfield 1979 X (= 1979~) are discussed. The brightness behavior of this comet is fairly well represented by the following magni­ tude formula, found through a least-squares regression analysis of 117 selected observa­ tions: m1 = 8.10 + 5 log 6 + 7.69 log r, where m1 is the aperture-corrected, total visual of the comet, and 6 and r are the comet's geocentric and heliocentric distances respectively.

I. Introduction

On 1979, December 24 veteran comet hunter William A. Bradfield of Dernancourt, South Australia, discovered his tenth comet while sweeping only 5 degrees south of Antares; the object was of magnitude 5 with a 1° tail. Comet Bradfield 1979 X (= 1979~) then was already 3 days past perihelion, being strictly a Southern-Hemisphere object until around 1980, January 27. On January 26 the comet passed within 0.2 A.U. of the Earth; and this extremely diffuse object was observed visually to be as much as 20'-25' in diameter during late January and early February, despite the occurrence of Full Moon on February 1. Full Moon also occurred on January 2 and March 1. Marsden (1980) has computed the following elements based on 17 observations from 1979, December 26 to 1980, January 17:

T 1979 Dec. 21.609 E.T. 102~5081 q 0.54529 A.U. 257. 597 l- 1950.0 e 0.98801 148.604j Morris (1980a, b) has commented on the apparition of comet 1979 X and on the object's brightness behavior.

II. Visual Appearance

On January 29, the first author located Comet Bradfield 1979 X with the 23-cm (9-inch) Clark refractor at Harvard College Observatory, finding it difficult near the horizon, with competing moonlight. Sightings rapidly increased as the Moon rose later, and the comet gained altitude, with the passage of a few days. However, the object's rapid daily motion at this time confused some observers who tried to locate it at ephemeris positions (predicted) for oh E.T. on a given date. Table 1A lists the A.L.P.O. observers of Comet Bradfield 1979~, of whom Clyde and Fulle contributed the greatest number of observations. Most of the A.L.P.O. observa­ tions were published in detail in the International Comet Quarterly (ICQ , Vol. 3, No.2, April 1981). -- - Raisanen found the comet on February 1 as having a noticeable tail. Visual reports of this narrow gas tail continued throughout the apparition, while photographs naturally revealed much longer tail lengths. Visual tail length estimates up to 1 degree were reported during the first two weeks of February. Pedroncelli found the comet as a circular, diffuse object on February 2 and 3. Karl and Wanda Simmons found the coma diameter to be as much as 25' in 7x50 binoculars on January 30; and this value was consistent with early February observations, indicating a true diameter of about 275,000 kms. Kronk noted the difficulty in determining the diameter of Comet 1979 X visually during February because the coma boundaries were very ambiguous. Stegmann reported the comet's appearance on February 5 as a "diffuse, nebulous glow."

III. Magnitude Analysis

The comet's large size and diffuseness also caused magnitude estimates to vary tremendously on a given night. The Sidgwick (In-out) or Morris methods should have been used for this type of comet, and not the Bobrovnikoff method which is most often used (cf. Morris 1980c). In addition to magnitude estimates made by A.L.P.O. observers, brightness data were compiled from those published in 1980 in the ICQ for analysis. Those observers whose ICQ observations were used in this study are presented in Table IB. After approximate estimates were deleted, only one observation per observer per night was retained. Other

45 FULL 0 MOON ++ ::1' + 0 l + FULL MOO I! 0 (0 1 en. + + + + + + ++ 0 (0. (0

(.!)O a:o ::::Ecx:) :::c + +

0 C\1 FULL ...... MOON J, FIGURE 1. COMET 1979 X: + LOGARITHMIC PLOT OF HELIOCENTRIC 0::1' + DISTANCE (R) VERSUS HELIOCENTRIC (0 MAGNITUDE (H MAG), WITH THE LEAST SQUARES FIT: + H0 = 8.10 + 7.69 LOG R. 0 (0 117 OBSERVATIONS REPRESENTED. ++ 1/)

+ 0 (0 +------r-----,.-----.------.------.-----~~--~~ ::1'-0.32 -0.2Y -0. I6 -0.08 0.00 0.08 0.16 0.2Y LOG R observations had to be deleted because of uncertainty about which instruments were used for certain magnitude estimates. Also, those observations which did not list a source catalog for the comparison stars (needed for a good magnitude estimate) were usually deleted. The remaining 117 observations were used for a least squares regression analysis; and the magnitude estimates were reduced to a standard aperture of 6.78 em, after Morris (1973). The regression analysis used was that described by Green (1980a, b), and produced the following values for , H0 , and the characteristic brightness para­ meter, n: n 3.08 + 0.13 (p.e.)

H0 8.10 ~ 0.03 (p.e.). When these values are placed in the standard cometary magnitude formula, one obtains m1 = 8.10 + 5 log 6 + 7.69 log r, ( 1 ) where m1 is the observed total visual (aperture-corrected) magnitude, and 6·and rare the comet's geocentric and heliocentric distances respectively. Figure 1 graphically indicates the fitted line from the above parameters as drawn through the 117 magnitude data points. Fig. 1 shows well the scatter in magnitude estimates during February (center of graph) caused by the difficulty of making a reliable estimate. While this comet may have previously passed through the inner Solar System, its H0 - and n-parameter values are not unusual for either a "new" or an "old" comet. (Text continued below Table II on page 49)

46 TABLE IA. LIST OF A.L.P.O. OBSERVERS (Listed here are those observers who contributed observations directly to the A.L.P.O. Comets Section. A "10" after the column-1 name code indicates observers who made observations that were contributed by M. Grossmann of West Germany.)

CAP CHARLES F. CAPEN, AZ, U.S.A. CLY ROBERT CLYDE, OH, U.S.A. FUL M. FULLE, ITALY JEN 10 GUENTER JENNER, AUSTRIA KR002 GARY W. KRONK, IL, U.S.A. MAT02 LEONARD MATUSZEWSKI, NJ, U.S.A. OME STEPHEN O'MEARA, MA, U.S.A. PED JOSEPH W. PEDRONCELLI, NM, U.S.A. RAI RODNEY J. RAISANEN, OH, U.S.A. REI 10 PETER REINHARD, AUSTRIA SCHOJ 10 MICHAEL SCHMID, AUSTRIA SIM KARL SIMMONS, FL, U.S.A. SIM01 WANDA SIMMONS, FL, U.S.A. STE01 CHRIS STEPHAN, OH, U.S.A.

TABLE IB. LIST OF OTHER OBSERVERS (This table lists those observers whose observations have been published in the ICQ, but who did not contribute directly to the A.L.P.O.) BEN JACK C. BENNETT, SOUTH AFRICA BOE LEO BOETHIN, THE PHILIPPINES BOR JOHN E. BORTLE, NY, U.S.A. GLI GUNNAR GLITSCHER, WEST GERMANY GRE DANIEL W. E. GREEN, NC, U.S.A. HAR01 SYOJI HARADA, JAPAN HON KEN HONDA, JAPAN MAY MARVIN J. MAYO, CA, U.S.A. MIZ YOSHIKANE MIZUNO, JAPAN MOR CHARLES S. MORRIS, MA, U.S.A. MOR02 JAMES A. MORGAN, WI, U.S.A. NAKOJ MASATSUGU NAKAMURA, JAPAN SAT MASAAKI SATAKE, JAPAN SHE CLAY SHERROD, AR, U.S.A. suz KENZO SUZUKI, JAPAN TAN TETSUO TANAKA, JAPAN TRE T. B. TREGASKIS, AUSTRALIA

TABLE II. MAGNITUDE OBSERVATIONAL ANALYSIS.

No. Date (U. T.) Mag. Corr. In st. H-Mag. Delta r log r Obs. 1 1979 12 26.740 5.40 5.50 5.0B 5.15 1.174 0.555 -.2557 TRE 2 1979 12 29.080 5.60 5.78 3.5B 5.62 1.076 0.571 -.2434 BEN 3 1979 12 31.080 5.50 5.68 3.5B 5.66 1.008 0.586 -.2321 BEN 4 1980 1 1. 740 5.80 5.90 5.0B 5.96 0.973 0.595 -.2255 TRE 5 1980 1 6.740 6.20 6.30 5.0B 6.80 0.795 0.648 -.1884 TRE 6 1980 1 7.740 6.00 5.94 10.0L 6.54 0.759 0.660 -.1805 TRE 7 1980 1 16.680 5.80 5.90 5.0B 7. 71 0.434 0.786 -.1046 TRE 8 1980 1 20.750 5.00 5.10 5.0B 7.69 0.303 0.847 -.0721 TRE 9 1980 1 21.480 4.70 4.80 5.0B 7.60 0.275 0.863 -.0640 TRE 10 1980 1 25.830 4.70 4.41 12.0R 7.90 0.201 0.927 -.0329 BEN 11 1980 1 26.760 4.70 4.41 12.0R 7.93 0.198 0.943 -.0255 BEN 12 1980 1 27.980 4.80 4.90 5.0B 8.36 0.203 0.959 -.0182 BOR 13 1980 1 28.020 4.70 4.63 8.0B 7.97 0.215 0.975 -.0110 MOR 14 1980 1 28.960 6.00 5.93 8.0B 9.27 0.215 0.975 -.0110 OME 15 1980 1 28.990 5.10 5.20 5.0B 8.54 0.215 0.975 -.0110 BOR 16 1980 1 29.030 5.10 5.03 8.0B 8.20 0.233 0.992 -.0035 MOR 17 1980 1 29.990 5.30 5.40 5.0B 8.56 0.233 0.992 -.0035 BOR 18 1980 1 30.010 5.60 5.70 5.0B 8.67 0.255 1.008 0.0035 SIM 19 1980 1 30.030 5.30 5.23 8.0B 8.20 0.255 1.008 0.0035 MOR 20 1980 1 30.400 5.50 5.44 10.0L 8.41 0.255 1.008 0.0035 HAR01 21 1980 1 30.500 5.50 5.38 13.0L 8.35 0.255 1.008 0.0035 MIZ 22 1980 1 30.500 5.70 5.88 3 .5B 8.85 0.255 1.008 0.0035 suz 23 1980 1 30.500 5.80 5.90 5.0B 8.87 0.255 1.008 0.0035 TRE 24 1980 1 30.510 5.50 5.60 5.0B 8.57 0.255 1.008 0.0035 NAK03 25 1980 1 31.000 5.50 5.60 S.OB 8.35 0.282 1.024 0.0103 BOR 47 TABLE II. MAGNITUDE OBSERVATIONAL ANALYSIS. (Cont 'd.) No. Date (U. T.) Mag. Corr. Inst. H-Mag. Delta r log r Obs. 26 1980 1 31.020 5.60 5.53 8.0B 8.28 0.282 1.024 0.0103 MOR 27 1980 1 31.400 5.50 5.38 13.0L 8.13 0.282 1.024 0.0103 MIZ 28 1980 1 31.510 5.80 5.98 3.5B 8.73 0.282 1.024 0.0103 suz 29 1980 1 31.520 5.70 5.64 lO.OL 8.39 0.282 1.024 0.0103 HAROl 30 1980 1 31.760 5.60 5.53 8.0B 8.28 0.282 1.024 0.0103 GLI 31 1980 2 1.010 5.70 5.80 5.0B 8.34 0.310 1.040 0.0170 !IOR02 32 1980 2 1.040 6.10 6.20 5.0B 8.74 0.310 1.040 0.0170 SHE 33 1980 2 1.400 6.00 5.88 13.0L 8.43 0.310 1.040 0.0170 MIZ 34 1980 2 1.420 6.50 6.60 5.0B 9.14 0.310 1.040 0.0170 NAK03 35 1980 2 1.420 6.50 6.34 15.0L 8.89 0.310 1.040 0.0170 TAN 36 1980 2 1.500 6.20 6.30 5.0B 8.84 0.310 1.040 0.0170 HAROl 37 1980 2 1.500 6.00 5.94 10.0L 8.48 0.310 1.040 0.0170 HON 38 1980 2 1.530 6.20 6.30 5.0B 8.84 0.310 1.040 0.0170 THE 39 1980 2 1.800 5.80 5.79 7.0R 8.33 0.310 1.040 0.0170 FUL 4Q 1980 2 2.000 5.90 5.83 8.0B 8.17 0.341 1.057 0.0241 MOR 41 1980 2 2.000 6.50 6.05 15.0R 8.38 0.341 1.057 0.0241 SHE 42 1980 2 2.010 7.40 7.22 10.0B 9.56 0.341 1.057 0.0241 SIM 43 1980 2 2.110 6.00 6.10 5.0B 8.43 0.341 1.057 0.0241 MOR02 44 1980 2 2.400 6.00 5.94 lO.OL 8.28- 0.341 1.057 0.0241 HON 45 1980 2 2.470 6.30 6.40 5.0B 8.73 0.341 1.057 0.0241 HAROl 46 1980 2 2.530 6.30 6.03 21.0L 8.37 0.341 1.057 0.0241 SAT 47 1980 2 2.540 6.00 6.18 3.5B 8.52 0.341 1.057 0.0241 suz 48 1980 2 3.000 5.70 5.80 5.0B 7.93 0.374 1.073 0.0306 BOR 49 1980 2 3.000 6.00 6.10 5.0B 8.23 0.374 1.073 0.0306 !lOR S!.! 1980 2 3,010 6.00 6.10 5.0B 8.23 0.374 1.073 0.0306 MOR02 51 1980 2 3.440 6.20 6.38 3.5B 8.52 0.374 1.073 0.0306 suz 52 1980 2 3.450 5.90 5.84 lO.OL 7.97 0.374 1.073 0.0306 HON 53 1980 2 3.790 6.20 6.19 7.0R 8.32 0.374 1.073 0.0306 FUL 54 1980 2 3.980 5.90 6.00 5.0B 8.13 0.374 1.073 0.0306 MOR 55 1980 2 4.000 5.80 5.,90 5.0B 7.85 0.407 1.089 0.0370 BOR 56 1980 2 4.020 6.30 6.40 5.0B 8.35 0.407 1.089 0.0370 MOR02 57 1980 2 4.050 6.70 6.63 8.0B 8.58 0.407 1.089 0.0370 GRE 58 1980 2 4.130 6.20 5.91 12.0R 7.86 0.407 1.089 0.0370 MAY 59 1980 2 4.740 6.60 6.59 7 .OR 8.54 0.407 1.089 0.0370 FUL 60 1980 2 4.760 6.50 6.68 3 .5B 8.63 0.407 1.089 0.0370 BEN 61 1980 2 4.980 6.10 6.20 5.0B 8.15 0.407 1.089 0.0370 MOR 62 1980 2 5.020 6.20 6.30 5.0B 8.08 0.441 1.106 0.0438 BOR 63 1980 2 5.090 6.70 6.80 5.0B 8.58 0.441 1.106 0.0438 MOR02 64 1980 2 5.420 6.70 6.51 17.0L 8.28 0.441 1.106 0.0438 NAK03 65 1980 2 5.460 6.80 6.74 lO.OL 8.52 0.441 1.106 0.0438 HAROl 66 1980 2 5.540 6.60 6.78 3.5B 8.56 0.441 1.106 0.0438 suz 67 1980 2 5.800 6.80 6.79 7.0R 8.57 0.441 1.106 0.0438 FUL 68 1980 2 6.020 6.40 6.50 5.0B 8.11 0.476 1.122 0.0500 MOR 69 1980 2 6.030 6.40 6.50 5.0B 8.11 0.476 l.P2 0.0500 BOR 70 1980 2 6.410 7.60 7.54 lO.OL 9.15 0.476 1.122 0.0500 HAROl 71 1980 2 6.500 6.70 6.88 3 .5B 8.49 0.476 1.122 0.0500 suz 72 1980 2 6.560 6.90 6.65 20.0L 8.26 0.476 1.122 0.0500 SAT 73 1980 2 7.080 7.00 7.10 5.0B 8.56 0.511 1.138 0.0561 MOR02 74 1980 2 7.480 6.70 6.64 lO.OL 8.10 0.511 1.138 0.0561 HON 75 1980 2 7.520 7.00 6.73 21.0L 8.19 0.511 1.138 0.0561 suz 76 1980 2 7.760 6.90 6.89 7.0R 8.35 0.511 1.138 0.0561 FUL 77 1980 2 8.830 7.00 6.99 7.0R 8.30 0.547 1.155 0.0626 FUL 78 1980 2 9.010 7.10 7.03 8.0B 8.20 0.583 1.171 0. 0686 MOR 79 1980 2 9.020 7.00 7.10 5.0B 8.27 0.583 1.171 o. 0686 MOR 80 1980 2 9.520 7.60 7.33 21.0L 8.50 0.583 1.171 0.0686 suz 81 1980 2 10.020 7.30 7.40 5.0B 8.44 0.619 1.187 0.0745 MOR02 82 1980 2 10.020 7.30 7.23 8.0B 8.27 0.619 1.187 0.0745 MOR 83 1980 2 10.990 7.30 7.40 5.0B 8.44 0.619 1.187 0.0745 MOR 84 1980 2 11.760 7.50 7.49 7.0R 8.41 0.655 1.203 0.0803 FUL 85 1980 2 12.010 7.50 7.60 5.0B 8.40 0.692 1.220 0.0864 MOR 86 1980 2 12.560 8.30 8.14 15.0L 8.94 0.692 1.220 0.0864 TAN 87 1980 2 12.800 7.70 7.69 7.0R 8.49 0.692 1.220 0.0864 FUL 88 1980 2 13.020 7.80 7.73 8.0B 8.42 0.728 1.236 0.0920 MOR 89 1980 2 13.460 8.40 8.21 17.0L 8.90 0. 728 1.236 0.0920 NAK03 90 1980 2 13.990 7.80 7.73 8.0B 8.42 0. 728 1.236 0.0920 MOR 91 1980 2 14.800 8.00 7.99 7.0R 8.57 0.765 1.252 0.0976 FUL 92 1980 2 15.490 8.80 8.61 17.0L 9.08 0.802 1.268 0.1031 NAK03 93 1980 2 15.490 8.60 8.44 15.0L 8.92 0.802 1.268 0.1031 TAN 94 1980 2 16.030 8.10 8.03 8.0B 8.42 0.838 1.284 0.1086 MOR 95 1980 2 17.070 8.20 8.16 7 .5R 8.45 0.875 1.300 0.1139 MOR02

48 TABLE II. MAGNITUDE OBSERVATIONAL ANALYSIS (Cont'd.) No. Date (U.T.) Mag. Carr. Inst. H-Mag.Delta r log r Obs. 96 1980 2 17.460 8.20 8.14 10.0L 8.43 0.875 1.300 0.1139 HAR01 97 1980 2 17.470 8.60 8.44 15.0L 8.73 0.875 1.300 0.1139 TAN 98 1980 2 17.580 8.80 8.54 20.3L 8.83 0.875 1.300 0.1139 BOE 99 1980 2 18.000 8.40 8.33 8.0B 8.53 0.912 1.317 0.1196 MOR 100 1980 2 18.820 8.60 8.53 8.0B 8.73 0.912 1.317 0.1196 GLI 101 1980 2 19.020 8.40 8.33 8.0B 8.45 0.948 1.333 0.1248 MOR 102 1980 2 19.030 8.70 8.35 25.0L 8.47 0.948 1.333 0.1248 MOR 103 1980 2 19.490 8.70 8.54 15.0L 8.66 0.948 1.333 0.1248 TAN 104 1980 2 19.530 8.90 8.64 20.3L 8.76 0.948 1.333 0.1248 BOE 105 1980 2 19.890 8.60 8.53 8.0B 8.65 0.948 1.333 0.1248 GLI -='1"""067-:1~9:-':8:70----'2::--:;2~0-=-.70=::-40::----~8-=-.-:-80::------=8-=-. =:.:45::-----::2-::5-'-.· ::.,OL::-----::8-=-.-:-49 o-: 9 85--1:349 0 .13 00 MOR 107 1980 2 20.490 8.70 8.54 15.0L 8.58 0.985 1.349 0.1300 TAN 108 1980 2 20.620 9.00 8.74 20.3L 8.78 0.985 1.349 0.1300 BOE 109 1980 2 21.490 9.10 8.94 15.0L 8.90 1.021 1.365 0.1351 TAN 110 1980 2 21.620 9.00 8.74 20.3L 8.70 1.021 1.365 0.1351 BOE 111 1980 2 23.520 9.50 9.34 15.0L 9.15 1.094 1.396 0.1449 TAN 112 1980 2 24.020 9.40 9.36 7.5R 9.10 1.130 1.412 0.1498 MOR02 113 1980 3 2.050 9.90 9.86 7.5R 9.16 1.382 1.522 0.1824 MOR02 114 1980 3 4.500 11.30 11.04 20.3L 10.23 1.452 1.554 0.1915 BOE 115 1980 3 8.490 11.80 11.54 20.3L 10.53 1.592 1.615 0.2082 BOE 116 1980 3 9.500 11.90 11.64 20.3L 10.59 1.627 1.631 0.2125 BOE 117 1980 3 10.500 12.00 11.74 20.3L 10.64 1.662 1.646 0.2164 BOE

It is interesting to note that a small flare in brightness apparently occurred around February 31 causing the apparent magnitude to remain fairly constant for a few days even though Comet 1979 X was then moving away from the Earth (Morris 1980a). The 117 analysis observations are listed chronologically in Table II, where columns give the time of observation, the observed total visual magnitude, the aperture­ corrected magnitude, the instrument aperture (in em) and instrument type (R = refractor, L = reflector, B = binoculars) used for the magnitude estimate, the calculated helio­ centric magnitude, the comet's distances from the Earth and the Sun, the logarithm of the comet's heliocentric distance, and the observer (see Key in Table I). Acknowledgments Dennis Milan, A.L.P.O. Comets Recorder, supplied the A.L.P.O. observations used for this paper. Dr. Brian G. Marsden kindly provided the necessary computer time, at the Harvard-Smithsonian Center for Astrophysics, which was used for the reduction of the magnitude data of Comet 1979 X.

RefereYJces Green, D. W. E. (1980a). J.A.L.P.O., 28 (Nos. 7-8), pp. 134ff. Green, D. W. E. (1980b). J.A.L.P.0.,28 (Nos. 9-10), pp. 197ff. Marsden, B. G. ( 1980). M.P.C., 5176. - Morris, C. S. (1973). P.~., 85, 470. Morris, C. S. ( 1980a). I.C.O., 2-;- 23 (April, 1980). Morris, C. S. ( 1980b). I.C.O., ~. 24 (April, 1980). Morris, C. S. ( 1980c). I.C.O., .?_, 69ff. (October, 1980).

Figure 2. Series of sketches by Stephen J. O'Meara of thfi occultation of a ninth magnitude star by Comet Bradfield. Made on January 31, 1980 near 0 15m, U.T., using the 9-inch Clark refractor at 250X at Cambridge, MA. The coma was 15 minutes of arc in diameter with a mottled appearance and no nucleus. Mr. O'Meara noted that the star flickered several times during the occultation.

49 Of Comet Bradfi~ld ~979 X by PA at 0 30 , U.T. on at 71X. The 10 X 50 binoculars the 6.8. Compare to Figure on the same date.

Figure 4. Drawing of Comet Bradfield 1g7~ X by Leonard Matuszewski of Paramus, NJ at 0 0 , U.T. on February 4, 1980. 20 X 50 binoculars with 3° field. The coma was about 30' across.

Figure 5. Drawing of Comet Bradfield 1979 X by Stephen J. O'Meara on January 31.01, 1980, U.T. 9-inch Clark refractor and a high power. Figures 5 through 8 reveal details of the inner coma. They show a distinctly mottled central condensation with several bright points. Compare Figure 5 to Figures 2 and 3.

Figure 6. Another drawing of Comet Bradfield by Stephen J. O'Meara with a 9-inch refractor. February 4.00, 1980, U.T. Compare to Figure 4 at same time and date.

Figure 7. Another drawing, by Stephen J. O'Meara, of Comet Bradfield. 9-inch refractor, February 5.01, 1980, U.T.

50 Figure 8. Drawing of Comet Bradfield by Stephen J. O'Meara on February 6.00, 1980, U.T. 9-inch Clark refractor and a high power.

WHAT IS NEW ON MARS-MARTIAN 1979-1980 APPARITION REPORT II By: C. F. Capen and D. C. Parker, A.L.P.O. Mars Recorders (Concluded from preceding issue) [The first part of this Mars Report appeared in Volume 29, Nos. 1-2 of this journal, pages 38-42. Readers may want to refer back to the text and diagrams there.]

The Martian Arctic

During the Martian late spring season of the aphelic apparition of 1888, G. Schiaparelli found the North Polar Cap to be divided into two unequal parts by a dark fissure or rift located along the 150°-330° W areographic meridians. He named it RIMA TENUIS (thin or fine fissure). This furrow within the North Cap was later confirmed by his contemporaries, Perrotin and Terby. It was again well seen at the same Martian season, 61°-65°Ls, in 1901 by A. E. Douglass at Flagstaff, and yet again but much more pronounced in 1903 by P. Lowell at Flagstaff. A similar appearance of the rift was again reported in 1918 by M. Maggini at Florence. An unsuccessful search was made for Rima Tenuis in the 1960's by C. Capen using large telescopes of 61 em to 208 em (24-in.- 82-in.) apertures. Mariner and Viking photography showed no trace of the dark rift during the 1970's. Rima Tenuis unexpectedly appeared again across the NPC before the Martian northern summer solstice in 1980, when it was easily seen and photographed with tele­ scopes of only 20 cm-30 em (8-in.-12-in) apertures by A.L.P.O. astronomers. See Figures 9 and 13. While observing Mars with the 30 em and 61 em Clark refractors at the Lowell Observatory on the night of February 22, 1980, Patrick Moore and Chick Capen detected a very bright projection bordering a dark notch on the edge of the NPC at about 320°- 3300 W long. The rift was better seen on the following night when it was noted to extend farther into the cap. A phone call from Don Parker confirmed the Rima Tenuis rift; and he observed the thin, dark line to extend completely across the cap, dividing it into two unequal parts, approximately along the 325° W-150° W meridians. According to Mars observation reports which have been received and catalogued to date, other A.L.P.O. astronomers who independently rediscovered this thin dusky feature are, chronologically: Daniel Troiani, Chicago; Jean Dragesco, Republic Benin, Equatorial Africa; Jeff Beish, Miami; Leo Aerts, Belgium; Maurice Gavin, England; Alan Macfarlane, Seattle; and Charles Evans, Hampton, VA. The astrophotographers who captured this elusive feature upon film are: L. Aerts, Feb. 14, 10 em refr.; D. Parker, Feb. 20 and 24 and Mar. 26, 31 em Newt; A. Marfarlane, Feb. 22, 20 em C-8 Sm-Cass; C. Capen, Feb. 22 and 23, 31 em refr.; and D. Troiani, Feb. 26, 25 em Newt. The black-and-white S0-115 (Tech. Pan 2415) film or color Ektachrome slide film was used. It is indeed rewarding to learn that so many observers independently detected this almost unknown and quite unexpected feature! Why doesn't Rima Tenuis form regularly each Martian year, as does the peripheral bright patch Olympia located at 210° W longitude, which is separated from the cap by Chasma Boreale? One explanation is that the Martian arctic climate is variable over a time span as short as a decade or two. The Mariner and Viking spacecraft data showed a change in polar deposits from year to year. These observed changes in the polar cap behavior and appearance prompted an extensive search of all historical and present telescopic literature. The search through two dozen volumes written in eight different languages and over 100 charts of Mars proved fruitful. Independent measurements of the NPC diameters through the years by Antoniadi, Dollfus, Miyamoto, Capen, Iwasaki, and Parker showed a variable regression rate over short periods within decades. A negative correlation between the presence of Rima Tenuis and the North Cap diameter was found. When the northern summer cap remnant was smaller in diameter, i.e., 5° to 7°, as it was in 1888, 1901, 1903, 1918, and again in 1980, the Rima Tenuis was observed. When the summer cap was large, as in 1898 and other years, the dark rift was not seen. The

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51 Figure 9 shows the Martian Arctic Region during winter, spring, and summer in these selected photographs, photo-visual images, and visual observations made by A.L.P.O. international Mars astronomers during the 1979-80 apparition. The sudden and unexpected appearance and evolution of the unique dark fissure, Rima Tenuis, which cut the NPC into two unequal parts, is well docu­ mented. South is shown up, as in a telescopic view. Identification code: Year, Month, U.T. Date, Color Filter, U.T. (Universal Time), CM (Central Meridian), Ls (Season Orbital Position), MD (Martian Date), Telescope Type, X (Maximum Power), Observer, Location, and Remarks. Dashed lines indicate cloud boundaries; dotted lines, bright frosts, or ice-fogs. Row 1, left to right: 1) 79 06 06 B 0955 U.T. CM 352°; Ls 300° (Jan. 23 MD); 32 em Newt. Refl. 515X. Don C. Parker, Coral Gables, FL. A broad blue-light image shows a large winter, dull gray NPH and vague sur­ face features. Mars at great distance from Earth with apparent diameter of 4~2. 2) 79 10 27 R 1100 U.T. CM 60°; Ls 17° (Apr 7 MD); 18 em Refr. 250X. Mike Holland and John Barnett, RAS Observatory, Richmond, VA. Bright spring cap is seen free of winter polar cloud hood. Apparent disc diameter 6". 3) 7~ 11 20 I 0510 U.T. CM 104°; Ls 28°; 20 em Sch/Cass. 280X. Jean Dragesco, Cotonou, Pop.Repb. Benin, Eq. Africa. Large, bright NPC. No polar dark collar noted. 4 I 79 12 10 Y, G, B, M 1225 U.T. CM 19°; Ls 37° (Apr 27 MD); 61 em Refr. 250X. Len Bierman, Flagstaff, AZ. Rapidly shrinking NPC developing a dark polar collar. A SPH is noted. Row 2: 51 79 12 14 I, R 1100 U.T. CM 322°; Ls 38° (Apr 30 MD); 25 em Newt. 283X. Daniel M. Troiani, Chicago, IL. The dark collar is confirmed. First evidence of a NPC rift notch at about 325°- 3300 W. longitude, which later in the season developed into the Rima Tenuis fissure. 6) 79 12 15 R, Y, B 0940 U.T. CM 293°; Ls 39°; 15 em Newt. 245X. Rob Robotham, Port Rowan, Ontario, Canada. Rapid thawing NPC. A wide, dark collar with independent confirming evidence of the Rima Tenuis notch. 7) 79 12 15 P-V, I 1007 U.T. CM 299°; Ls 39°; 32 em Newt. @ f/158, Film Tech Pan 35mm (TP 135)= S0115, 4 sec. exp. D. C. Parker, Coral Gables, FL. Photo-visual image showing irregularity of NPC edge at the Rima Tenuis notch (JZ0°-330~ WI. Syrtis Major triangle seen at upper left. Martian disk shows large phase. 8) 7~ 12 25 I 0503 U.T. CM 131"; L 44° (May 4 MD); 20 em Sch/Cass. Jean Dragesco, Pop. Repb. Benin, Eq. Africa. On the opposi~e side of Mars can be seen the other Rima Tenuis notch starting to penetrate the NPC at 150° W longitude. Row 3: 9) 80 02 10 P-V, I 0510 U.T. CM 66°; Ls 64° (May 26 MD); 32 em Newt. @ f/158, Film Tech Pan35mm (SO 115), 4 sec. exp. D. C. Parker, Coral Gables, FL. Photo-visual image of the Acidalium-Tempe region. On the right of the NPC can be seen the bright peripheral patch known as Olympia located at 210° W longitude, which is separated from the cap by the broad, dark fissure, Rima Borealis (Chasma Boreale). 10) 80 02 14 P-V, I 0100 U. T. CM 330°; Ls 66°; 10 em Refr. 214X and @ f/15, Tech Pan 35mm ITP 135) Film, 2 sec. exp. Leo Aerts, He1st-op-den-Berg, Belgium. Photo v1sual 1mage of Syrtis Major - Sabaeus S. region shows the dark rift notch and a peripheral bright patch on its right. The small original photo (insert) also shows this bright projection on the edge of the late spring cap. 11) 80 02 19 I 2245 U.T. CM 245°; Ls 68° (May 30 MD); 30 em Refl. 300X. Maurice Gavin, Surrey, England. The Alcyonius-Utopia region is seen; and a small NPC with an encompassing dark collar and the dark, narrow fissure extending half-way through the cap. 12) 80 02 22 P-V, I 0630 U.T. CM 341°; Ls 69°; 20 em Sch/Cass. 335X and 6mm eyepiece proj. Film EL 135 (Ekta 400 ASA). Alan W. MacFarlane, Seattle, WA. Again, the Syrtis-Sabaeus region is seen on this photo-visual image. The original hi-speed Ektachrome slide and several color prints show the Rima Tenuis fissure to extend fully across the visible NPC. Note the three dark spots just above the NPC. Two of them collate with the Ismenius Lacus located at 340° W. Row 4: 13) 80 02 23M, R, Y, G, B, V 0600 U.T. CM 325°; L 70° (May 31 MD); 61 em Refr. 810X. Chas F. Capen, Flagstaff, AZ. The dull, gray SPH, late ~pr1ng equator1al clouds, and the aspect of the retreating NPC are seen in the Syrtis-Sabaeus region of Mars. The dark polar collar and fine structure of Rima Tenuis are present upon the disk. 14) 80 02 24 I 0514 U.T. CM 305°; Ls 71°; 25 em Newt. 4mm eyepiece proj. Film Tech Pan 35mm (S0- 115). Daniel M. Troiani, Chicago, IL. The Rima Tenuis was recorded on the original photo print. 15) 80 02 24M 0630 U.T. CM 324°; L 71° (June 2 MD); 32 em Newt. 775X D. C. Parker, Coral Gables, FL. A thin, dark collar surround~ the small bright NPC. Rima Tenuis is well noted across the cap. 16) 80 02 24 P-V, I 0720 U.T. CM 336°; L 71°; 32 em Newt. @ f/156; Film TP 135 (S0-115), 4 sec. exp. D. C. Parker, Coral Gables, FL. The Syrtis-Sabaeus region is shown. Rima Tenuis was well recorded on original photograph. Row 5: 17) 80 03 09 M, Y, G, B, V 0425 U.T. CM 171°; Ls 77° (Jun 8 MD); 32 em Newt. 760X. D.C. Parker, Coral Gables, FL. Active spring weather is seen over the Elysium region. The other end of the Rima Tenuis is noted crossing the cap at about 150° W longitude. Consequently, this fine fissure cuts the North Cap into two unequal parts. 18) 80 03 26 I 0415 U.T. CM 18°; Ls 84° (Jun 16 MDl;,32 em Newt. @ f/158; Film Tech Pan 35mm (S0- 115); 4 sec. exp. D.C.Parker, Coral Gables, FL.Tne Mare Acidalium region. A small, late spring NPC with a thin, dark collar. 19) 80 04 06 I 0230 U.T. CM 254°; L 89° (Jun 20 MD); 23 em Refr. 310X. Stephen O'Meara, Cambridge, MA. A salient bright patch is ~een on the morn1ng s1de of the NPC, and a dark collar is still present in late Martian spring. 20) 80 05 18 I 1100 U.T. CM 346°; Ls 108° (Jul 10 MDI; 20 em Newt. 400X. Morimasa Nakajima, Yoko­ hama, Japan. A small bright static North Cap remnant is present in early Martian summer. The dark collar had disappeared. The SPR and Hellas were covered by a bright polar hood of winter clouds. Figure 9. Selected A~L.P~O. drawings and phc,tographs of f'.'1ar~s during the 1979-80 apparition. Notes and relevant data for each Mars i.mage on page

53 Fig. 1 o. Mars Chart 1980 produced from orange-light observations made with a 4.5-inch (11.3cm) Newt. Rl. telescope by Christian Shambeck, Adelshofen, w. Germany. Surface albedo features are only approximately plotted on the map grid. This chart shows what can be seen on the surface of Mars with the aid of an orange filter and a small telescope, The southern albedo features were faintly seen this aphelic apparition due to the wintery hazes in the south and the northward tilt of the globe of Mars.

Fig. 11, Sectional Mars Map 1979-80 including 18oow to 120°W long­ itudes that illustrates the appearance and changes of ::Ce major albedo features observed by A.L.P.O. astronomers. Mr. c. Shambeck's Mars Chart 1980 was used as a base map. Refer to the text for a detailed description. sudden reappearance of this feature should stimulate further research upon spacecraft polar region data. A more thorough discussion of Rima Tenuis and its relationship to ~£rtian Arctic surroundings will appear later elsewhere. Martian Atmosphere During this apparition the north pole of Mars was tilted 15° to 22° toward the Earth, allowing a study of Martian weather within the northern hemisphere during late winter, spring, summer, and early autumn. Martian atmospheric condensates were well observed by A.L.P.O. astronomers from Jan., 1979 through Sept., 1980. An increase in morning and evening limb hazes and individual white clouds was noted in violet and blue light during Martian mid-spring. Bright patches of frosts and ice-fogs began to appear in Tempe, Arcadia, Cydonia, Elysium, and Nymphaeum through most color filters. Neat, round, white clouds appeared on the up-slopes of the volcanos about noon-time near the end of spring, 70°-90°Ls. These orographic H2o clouds continued to increase in size and brilliancy in early northern summer. A frequency catalog and critical grid-overlay measurements of positions will add to our understanding of the seasonal behavior of these condensates. Refer to illustrations for this article. Perhaps the most interesting phenomenon observed during this apparition within the Martian atmosphere was the extensive Violet-clearing, sometimes called Blue-clearing. Since E. C. Slipher, Lowell Observatory,first discovered this enigmatic phenomenon in the 1920's, scientists from many disciplines have tried to explain the rapid change it causes in the appearance of the Martian disk, a change easily detected with a Wratten 47 violet filter and a small or medium size telescope. In early February, 1980, 60° L , Michael Boschat, Halifax, Nova Scotia and Daniel Troiani, Chicago reported the begin~ing of a

54 long period of violet-clearing that was observed during Martian late spring and early summer. A.L.P.O. observers who cross-checked the Martian disk with violet W-47 filter vs. orange-red W-23 or red W-25 filters found a moderate (2) to strong (3) violet-clearing from February 3, 1980, 60° L , to Apr. 7, 89° L . Afterwards, the violet-clearing was noted to be weak (1) and int~rmittent through JUne 17, 1980, 121° L . A short description of how to observe this interesting phenomenon can be found in Ref. 1, and examples are shown in Figure 12. Martian Surface Although Mars was more than 63 million miles distant from the Earth during the 1979- 80 apparition, planetary observers who used yellow, orange, or red light filters recorded the appearance and intensity estimates of the light and dark albedo surface features well. Around the time of opposition, Feb. 25, many fine details were noted on the Martian disk. The large northern declination of the planet aided the quality of astronomical seeing. The conditions of the salient features are described below. Meridiani S. was very dark and conspicuous, while Sabaeus S. was faint and appeared to be broken or covered at times. The Daedalia-Claritas dark secular feature that was prominent in 1973, 1975, and 1978 was still present, but modified and less conspicuous in 1980. Perhaps this unusual topographic-controlled feature is fading from the face of Mars. The Ganges system was reported to be very dusky, broad, and conspicuous. Mare Acidalium darkened as the spring season progressed; and it was further enhanced in relative contrast by bright, white frosts or ice-fogs over the Nix Cydonia and Tempe­ Tanais areas bordering M. Acidalium. The Trivium Charontis-Cerberus was very weak, and at times not seen, while the Elysium volcanic shield brightened in late spring. To the west, the new secular darkening first discovered in 1978 along Hyblaeus C. (240° W; 30° N) had expanded across Aetheria and became most prominent in this region (Ref. 1). Syrtis Major was observed to be dark gray to blue-black, with its border outline approximately the same as mapped in 1967 and 1969, normal for this Martian season. To the southwest, Deltoton Sinus was very faded, and at times appeared as a half-tone desert area. The Casius, Coloe Pons, Protonilus, and Ismenius Lacus were dark and were well seen during most of the apparition. Nepenthes-Thoth was still weak and poorly seen most of the time. Nilosyrtis, Hiddekel, and Gehon lineaments were occasionally noted. Conclusion This Martian year was abnormal because of the observed apparent climatic change which occurred in the Northern Hemisphere. The unusually small North Cap remnant and the unexpected presence of Rima Tenuis indicated that the Martian Arctic Region was warmer than it has been in many decades. Not since the 1967 and 1969 apparitions has there been such an extensive and long period of violet-clearing observed on the Martian disk. The cap remnant was larger than normal in 1967 and 1969, indicating a cooler climate, so that violet-clearing does not appear to be influenced by climatic change. However, the frequency and occurrence of violet-clearing needs to be researched further. Although the seasonal white clouds have not been studied in depth, their occurrence and behavior appear normal. Certainly water cloud frequency should be affected by climate, tempera­ ture, and available water vapor from the thawing North Cap; consequently, there is a paradox here that needs to be resolved. So, the MARTIAN MYSTERY deepens! According to the A.L.P.O. observations, it would appear that Mars had an unusually warm northern summer during 1980. Also, the average temperatures of our own planet, Earth, were abnormally high in 1980. What affects both planets? The Sun. Wouldn't it be neat to be able to predict, in a general way, the weather upon the Earth by looking at Mars? The authors are presently reviewing terrestrial Northern Hemisphere temperature departures from the norm for the period 1881-1979, dates that were obtained from the Environmental Data and Information Service, U. S. Dept. of Commerce. There does, indeed, appear to be a correlation. The A.L.P.O. Mars Recorders, Don Parker and Chick Capen, wish to thank all of you who have contributed visual data, photographs, letters, and phone calls; these have enabled us to keep current on the changes which have occurred upon Mars these past two years. If you have not already mailed all of your current 1979-80 Mars observations to the Mars Recorders, please do so as soon as possible because all data are now being analyzed. We expect the coming 1982 Martian Apparition to be as exciting and rewarding and with new discoveries as was this past observing period. Since the Viking Orbiter Spacecrafts are now dead, there is nothing to keep an "Eye On Mars" except you, the Telescopic Observer! References 1. Capen, C. F. and D. C. Parker (1980). "The Martian 1979-1980 Apparition- A Pre- liminary Report, I", J.A.L.P.O., Vol. 28, Nos. 5-6, Apr. 2. Capen, C. F. ( 1980). "Return of the Martian Rima Tenuis", Bull. Am. Astro. Soc., Vol. 12, No. 3. 3. Capen, C. F. and Capen, V. W. (1970). "Martian North Polar Cap, 1962-68", Icarus, Vol. 13, No. 1, pp. 100-108. 4. Miyamoto, S. and Hattoria, A. (1968). "Polar Cap of Mars", Icarus, Vol. 9, No.3, pp. 440-445. 5. Parker, D. C. and Capen, C. F. (1980). "The Quest for the Universal Developer", J.A.L.P.O., Vol. 28, Nos. 9-10, Dec., pp. 179-184. 55 Figure 12 shows selected photographs, photo-visual images, disk drawings, and visual photometric intensity estimates (PIE) of Mars made during the 1979-80 apparition by A. L. P. 0. International Mars observers. Identification code: Year, Month, U. T. Date, Color Filter, U. T. (Universal Time), CM (Central Meridian), Ls ( S:;asonal Orbital Position), MD (Martian Date), Telescope Type, X (Maximum Power), Observer, Location, and Remarks. Dashed lines indicate cloud boundaries; dotted lines, bright frosts or ice-fogs. South is at top. Row 1, left to right: 11 79 07 16M, Y, B 1040 U.T. CM 333'; Ls 324' (Feb. 13 MDI; 32 em Newt. 415X. Don C. Parker, Coral Gables, FL. Mars seen at a great distance from Earth, with an apparent disk diameter of only 4". The NPH was seen well in blue and magenta light, but not in red or orange light. Extensive morning limb haze was present. The Syrtis Major and Sabaeus S. albedo features were dark. Nymphaeum ridge and Aeria appeared bright. A light notch was noted in L!el to tOn. 21 79 08 29 B 1102 U.T. CM 271'; Ls 347' (Mar. 7 MDI; 32 em Newt. @ f/260; Film EL 135 (Ektachrome 400 ASA), 2 sec. exp. D. C. Parker, Coral Gables, FL. A large and bright NPH is seen in this very distant, early apparition photo taken in blue light. 31 79 09 16 0 0930 U.T. CM 75'; Ls 357' (Mar. 16 MDI; 17.5 em Refr. 335X. John H. Barnett, Richmond, VA. The NPC is possibly clear of the winter hood. A bright patch is seen at the equator on the morning limb. Note the extreme gibbous phase of the disk. 41 79 10 01 I 1003 U.T. CM 296'; Ls 04' (Mar. 24 MDI; 25 em Newt. 283X. Daniel M. Troiani, Chicago, IL. A large, bright NPC free of the winter cloud hood was observed just after Martian northern Vernal Equinox. Several small, bright patches were noted in both hemispheres in the Syrtis-Sabaeus region. 51 79 10 20 I 0450 U.T. CM 38'; Ls 13'; 10 em Refr. 214X. Leo Aerts, Heist-op-den-Berg, Belgium. Early spring view of the M. Acadalium region and a large bright NPC. Row 2: 61 "19 11 10 I 0915 U.T. CM 260'; Ls 23' (Apr. 6 MDI; 32 em Newt. f/153 Film TP 135 IS0-1151 4 sec. exp. D. C. Parker, Coral Gables, FL. A photo of the dark Mare Tyrrhenum-Syrtis Major and the new spring NPC with a thin, just-forming, medium dark collar. 71 79 11 28 I 1010 U.T. CM 101°; Ls 32'; 32 em Newt. @ f/158: Film TP 135 IS0-1151 4 sec. exp. D. C. Parker. A photograph of the "hard seeing side" of Mars, the Tempe-Arcadia-Arnazonis region, and a rapidly thawing spring cap with a broadening dark collar. 81 79 12 09 0 1020 U.T. CM 359'; Ls 37' (Apr 26 MDI; 17.5 em Refr. 250X. Randy Tatum, Richmond, VA. Extensive SPH. Bright NPC with a dark collar. An early morning bright haze was noted over the Tempe. 91 79 12 14 I 1046 U.T. CM 319'; Ls 39'; 32 em Newt. @ f/156; Film TP 135 (S0-1151 4 sec. exp. D.C. Parker, Coral Gables, FL. A photo of the Syrtis-Sabaeus region. A large, bright spring NPC is seen. The morning limb is bright with haze on the equator. 101 79 12 31 I 0020 U.T. CM 6'; Ls 46' (May 6 MDI; 22 em Refl. 400X. Maurice V. Gavin, Surrey, England. A large SPH was observed. The NPC is rapidly thawing. Note the darker areas within the M. Acidalium. Row 3: 11 ) 80 01 06 I 1700 U. T. CM 194 °; Ls 49 °; 20 ern Newt. 400X. Morimasa Nakajima, Yokohama, Japan. Southern maria very dark on periphery of SPH. A noticeable but smaller NPC was recorded. Complex structure is seen in the Trivium Charontis and Elysium volcanic shield region. 121 80 0109 P-V 1008 U.T. CM 67'; Ls 50'; 32 em Newt. @ f/156; Film TP 135; 4 sec. exp. D. C. Parker. An irregular NPC is evident at the 90°-120° W longitude, located in Mare Boreurn north of Tempe. A photo­ visual image. 131 80 01 13 I 0857 U.T. CM 12'; Ls 52' (May 13 MDI; 32 em Newt.@ f/156; Film TP 135; 4 sec. exp. D. C. Parker. A bright, irregular NPC and a seasonally darkened M. Acidaliurn were recorded. The arc of the Tempes canal, which runs parallel to the west edge of M. Acidalium, was evident on the original print. The Ternpes C. was first recognized as a discrete albedo feature in the 1960's and was given its name by C. F. Capen. The Aran and Ophir appear bright. •. 14) 80 01 21 Y, I 0114 U.T. CM 187°; Ls 56°; 20 em Sch/Cass. 340X. Jean Dragesco, Pop. Repb. Benin, Eq. Africa. Many seasonal white clouds were noted. The Phlegethon-Erebus was very dark and broad leading into Trivium. The new dark secular albedo feature in the Aetheria region (230° W) is seen extending westward from Chaos to Nodus Alcyonius. 151 80 02 01 R, Y, G, B, V, M 1035 U.T. CM 225'; Ls 61' (May 21 MDI; 61 em Refr. 810X. C. F. Capen, Flagstaff, AZ. An extensive SPH, a rapidly thawing NPC with a dark collar, and springtime limb hazes were observed. The northern borders of southern maria were very dark. The Elysium volcanic shield appeared light. A good view of the new dark secular feature, Chaos-Morpheos, is shown extending across Aetheria to Alyconius. Row 4: 16) 80 ()2 05 I 2330 U. T. CM 19 °; L8 62 °; 83 ern Refr. 460X. ShirO Ebasawa, Planetary Research Observatory, Tokyo, Japan. An extraordinary view of the Sabaeus S., Margaritifer S., M. Acidalium, Moab, Eden, Cydonia, and Tempe regions. Many fine albedo features are evident across the entire Martian disk. The Ternpes streak paralleling the west border of M. Acidaliurn was clearly seen. 17) 80 02 10 I 2330 U.T. CM 335°; Ls 65°; 22 ern Refl. 215X. Maurice V. Gavin, Surrey, England. A small, brilliant NPC is seen with serrated dark collar. Note the several extremely dark areas within the dark albedo features. Seasonal evening and morning hazes and ice-fogs are indicated by broken lines. Visual photometric intensity estimates (0 brightest; 10 night sky) are given for many of the albedo features. 18) 80 02 11 B 0350 U. T. CM 38°; Ls 65 °; 25 em Newt. 240X. Jeffrey Moore, Norman, OK. The major albedo features are seen well in this blue light view, indicating a general blue-clearing across the Martian disk. The Tempe-Arcadia region appears brilliant through the blue filter. 191 80 02 12 B, V 0725 U.T. CM 81'; Ls 65'; 20 em Refl. 320X. D. Louderback, South Bend, WA. This vio­ let light view shows seasonal limb haze and cloud and a bright NPC with collar. Local blue-clearing is indicated in the extreme northern region of the planet. Row 5: 201 80 02 13 B, I 0312 U.T. CM 11'; Ls 66' (May 27 MDI; 15 em Refr. 343X. F. D. Bruner, Hope, IN. A shrinking NPC with a dark collar and a bright cap projection centered at 80° W longitude were observed. A morning cloud streak was noted in blue light, and a general blue-clearing was evident from the reported photometric intensity estimates. 211 so 02 13 I 0435 u.T. CM 32'; L 66'; 32 em Newt.@ f/158; Film TP 135; 4 ~ec. exp. D, C. Parker, Coral Gables, FL. Good photog~aphic details of Meridiani S., Margaritifer S., Aurorae S., M. Acidalium, and Nilokeras can be seen. The bright North Cap projection at 80° W, shown in Mr. Bruner's observation above, was confirmed in this photo. 22) 80 02 14 0, G, V 0300 U.T. CM ooo; Ls 66°; 12.5 em Sch/Cass. 312X. Michael E: Boschat, Halifax, Nova Scotia, Canada. Morning limb cloud is shown on equator over Candor-Tharsls. A moderate, general blue-clearing (2) was noted in violet light with a Wratten No. 47 filter. 23) 0002 14 I, Y, G, B 0600 U.T. CM 44°; L3 66°; 36 em Sch/Cass. 400X. Bill Roberts, Atlanta, GA. The image appears to be reverted, east limb toward west, as viewed with a star diagonal. A serrated NPC is further confirmed, and with a detached bright element at about 00° W longitude. Late spring haze and clouds were recorded.

56 Figure 12. Selected A.L.P.O. drawings and photographs of Mars during the 1979-80 apparition. Notes and revelant data for each Mars image on page 56. Figure 13. On the opposite page are selected photographs and drawings of Mars. Same description as in top paragraph on page 56.

Row 1, left to right: 0 0 1) 80 02 15 M,R,Y,G,B,V 0408 U.T. CM 07 ; Ls 67 ; 36 em Sch/Cass. 156X. Tom Peterson, Gadsden, AL. This Mars disk was drawn with a magenta filter. A serrated NPC is again noted with a dark collar. Extensive morning limb haze and a bright ice-fog over Tempe were observea. Much fine detail is drawn within the Margaritifer and Acidalium maria. 2) 80 0217 I,B, 0000 U.T. CM 290°; Ls 67°; 11.5Cil1Refr. 186X. In this beautiful rendering of Mars by Richard Baum, Chester, England, the details of Tritonis S., M. Tyrrhenum, Iapygia, and Syrtis Major in the south and Nodus Alcyonius, Casius, Utopia, and Umbra in the north are illus­ trated. An intriguing view of the faint Thoth-Nepenthes is shown. This region should be moni­ tored carefully during the next apparition. An early morning ice-fog is shown. 3) 80 02 17 I 0152 U.T. CM 316°; Ls 67°; 20 em Sch/Cass. 280X. Jean Dragesco, Be"nin, Equatorial Africa. About 2 hours later than image (2). Syrtis Major has rotated into late afternoon, and indeed the Nymphaeum ridge is bright white with probable frost. Hellas basin is a light misty gray. Much fine detail is seen across the Arabia-Eden desert. In the north, Ismenius-Deuteronilus­ Oxus is most striking bordering Cydonia. 4) 80 02 17 B 0730 U. T. CM 39°; Ls 67° (May 29 MD); 20 em Sch/Cass. 350X. Jeff Be ish, Miami, FL. After a 5 hour rotation from the observation in image (3) the M. Acdalium region is seen in blue light. Cydonia and Tempe are bright with frosts. A very bright evening cloud is seen on the left limb. The visibility of the albedo features indicates a general, moderate blue-clearing of strength 2 (Scale 0-J). Row 2: 5) 80 02 20 I 0355 U.T. CM 321°; Ls 69°; 32 em Newt. Refl. @f/158; Film TP 135; 4 sec. exp. D. C. Parker, Coral Gables, FL. This phcto shows well the albedo features Syrtis Major,Sabaeus S., Meridiani S., Umbra., and Cydonia. The Deltoton-Incurval is strangely weak, and the Sabaeus S. is verv weak. A dark collar surrounds the NPC, which is split by the dark rift, Rima Tenuis. 6) 80 02 22 I 1310 U.T. CM 79°; Ls 70°; 20 em Refl. 400X. Morimasa Nakajima, Yokohama, Japan. The Tharsis-Tempe-Arcadia region is rendered in the finest of detail with medium albedo features equally well seen in both hemispheres. The Ceraunius streaks southward from the ~brth· Cap • s dark collar and intersects the Nilus-Phlegethon streak at Mareotis L. A dark streak is seen to connect Ascraeus volcano with Olympica volcano. Little detail was noted within the Solis Lacus region, while just to the north the Baetis streak and Juventae Fans subsidence area and Ganges were clearly seen. 7) 80 02 23 M,R,Y,G,B,V 0455 U.T. CM 309°; Ls 70° (June 1 MD); 32 em Newt. 515X. D. C. Parker. This is a remarkable observation just before Mars reached opposition. Cloud and frost activity is seen at maximum when the NPC is rapidly thawing in late spring. A brilliant bright spot was noted on the NPC at intensity 0, while on both sides of the dark fissure, Rima Tenuis, the cap was estimated to be 0.5 intensity. Observation with a Wratten 47 violet filter indicated a strong, general blue-clearing of stren5th 3. 8) 80 02 23 B-G 2045 U. T. CM 181 ; Ls 70°; 11.5 em Refr. 186X. Richard Baum, Chester, England. A bright South Polar Hood was noted in blue-green light. Numerous late spring clouds were seen covering the Libya-Isidis basin in the morning, and the Amazonis-Arcadia during the evening. Row 3: 9) 80 02 26 I 0412 U.T. CM 273°; Ls 71°; 25 em Newt. 283X. Daniel M. Troiani, Chicago, IL. A small but valuable photo taken in integrated light shows the M. Tyrrhenum, Syrtis, and Umbra regions. Bright equatorial clouds extend inward from both limbs. 10) 00 03-03 I, B-G 1930 U.T. CM 85°; Ls 74°; 11.5 em Refr. 186X. Richard Baum, Chester, England. This interesting observation of the Tharsis-Tempe region shows a bright, discrete cloud on the west slope of Ascraeus Mons volcano. 11) 80 03 06 I,B 0515 U.T. CM 210°; Ls 75°; 25 em Newt. Refl. 380X. Jeff Moore, Norman, OK. Noted is a small, bright, shrinking NPC with a broad, dark collar. The large shield volcano, Elysium Mons, and the Libya basin appear bright. The new dark secular feature (the "Aetheria darkening"), the Chaos-Morpheos, was well recorded. 12) 80 OJ 06 R 0740 U.T. CM 245°; Ls 75°; J6 em Sch/Cass. @ f/70; Film TP 1J5 IS0-115), 1 sec. exp. HC 110-A developer. Howard F. Zeh, Temperance, MI. Many fine Martian features which are diffi­ cult to see visually are recorded on this excellent deep red Wratten Filter 29 photograph. A bright, late spring NPC is seen surrounded by a broad, dark collar; and at the opposite pole a dull gray SPH is present. A good view into the southern hemisphere shows a very dark M. Tyrrhenur.1, a moderately dark M. Cimmerium, and a dark M. Sirenum. The Syrtis Major has an abnormal oblong shape. Trivium Charontis and Cerberus are moderately dark, and the Cyclops canal is seen to connect with the Sinus Gomer. The Triton albedo streak is seen extending from the tip of Sinus Tritonis. The new dark secular Aetheria feature appears as a large dark blob just left of center. The Elysium shield volcano is brilliant white. It is evident from this very fine image that more photographs should be taken in red light and processed in a moderately active developer. Pre- cise measurements of albedo surface features can be made on images like this one. Row 4: 13) 80 OJ 10 I 0450 U.T. CM 169°; Ls 77°; J2 em Newt.@ f/158; Film TP 1J5 (S0-115); 4 sec. exp. D. C. Parker, Coral Gables. FL. This excellent composite image shows well the afternoon H20 clouds build-up on the slopes of the Tharsis Ridge volcanoes. Also seen are the Propontis dots in north center and the Styx-Trivium-Cerberus complex surrounding the bright Elysium shield on the morning limb. 0 0 14) 80 03 12 I 2235 U.T. CM 51 ; Ls78; 30 em Refl. 318X. Alan W. Heath, Nottingham, England. A small, late spring NPC is surrounded by a dark collar. On the NW border of M. Acidalium, the Nix Tanaica is seen bright in morning light. Compare this integrated (white) light observation with the next one made in violet light. 15) 80 OJ 12 V 2238 U.T. CM 52°; Ls 78 ; 30 em Refl. J18X. Alan W. Heath. This W-47 violet light observation shows much limb haze and a strong, general blue-clearing ( 3) across the Martian disk. 16) 80 03 19 I 0340 U.T. CM 7j0 ; Ls 81°; 17.5 em Sch/Cass. 300X. Clay Sherrod, Little Rock, AR. The NPC continues to shrink in size. Six dark albedo streaks can be seen associated with the salient Lunae Lacus, of which five were identified with classical canal-like structures. In the north, M. Boreum appeared dark. Row 5: 17) 80 02 21 I 0345 U.T. CM310°; Ls 69°; J2 em Newt.@ f/158; Film TP 1J5 ISP-1151; 4 sec. exp. D. C. Parker. This fine photo shows the maria Tyrrhenum, Syrtis Major,and Casius-Umbra to be very dark. Note the absence of Deltoton and Incurval. Ausonia and Iapygia are a light shade; Hadriacum and Ionium, which form the north rim of Hellas basin, are very dark. 18} 80 04 07 I, M 0500 U.T. CM 281°; Ls 89° (Jun 20 MD); 32 em Refr. 250X. Regulus Capen, Flagstaff, AZ. A large winter SPH and morning equatorial c1oud were noted in magenta light. A bright, cir­ cular patch was noted in the Libya basin. A small, bright NPC with dark collar was easily seen

by this ten-year old with untrained e~es. The 0 very dark Wedge-of -Casius was also confirmed. 19) 80 05 07 R,O,Y,G,B,V 0425 U.T. CM 354 ; Ls 103 (Jul 5 MD); 20 em Newt. 400X. Annette Wilson, Peoria, AZ. This blue-violet image shows the Sabaeus S. -Eden-Cydonia-M. Acidalium regions. A winter SPH and a small summer NPC remnant without a dark collar were noted. From the comparative different color observations contributed by Mrs. Wilson, a general weak to moderate blue-clearing ( 1-2l is indicated. 20) 80 06 05 V 0224 U.T. CM 48°; Ls 116°; 47 em Clark Refr. 280X. D. M. Troiani, Chicago, IL. Summer clouds were seen well in violet light. A strong, general blue-clearing (3) is indicated. 58 Figure 13. Selected A.L.P.O. drawings and photographs of Mars during the 1979-80 appa.r.i tion. Notes and relevant data for each Mars image on page 58.

59 Figure 14. Shown are selected visual observations and photometric intensity estimates of Mars made during the last part of the 1979-80 appari.tion by A.L.P.O. international Mars astronomers. Identification code: Year, Month, U.T. Date, Color Filter, U.T. (Uni.versal Time), CM (Central Meridian), Ls (Seasonal Orbital Position), MD (Martian Date), Telescope Type, X (Maximum Power), Observer, Locatio~ and Remarks. 1) 80 06 13 R, 0, Y, G, B, V 0145 U.T. CM 321°; L 120° (Jul. 23 MD); 25 em Cass. 208X. Charles L. Evans, Hampton, VA. Shown are visuil'l photometric intensity estimates (Scale: 10 brightest, 0 black sky) of the light and dark albedo areas in the Syrtis Major, Utopia, Umbra, and polar regions. 2) 80 06 17 I, R, B-G 0130 U.T. CM 279"; L 121°; 8.3 em Refr. 175X. Rob Robotham, Port Rowan, Ont., Canada. Three nights earlier than this drawing, the Syrtis seasonal cloud was observed to move across the Libya basin on to the Syrtis Major, obscuring its southern half. This disk drawing shows the entire east half of Syrtis covered by the seasonal cloud. The cloud also extended southward, covering part of M. Tyrrhenum and Oenotria. This summer cloud is fascinating to study because it can be observed to appear different in most colors, and with small telescopes, and also because of its rapid movement from to day. 3) 80 08 27 0, G, B 0030 U.T. CM 292"; L_ 157° (Aug. 30); 20 em Sch/Cass. 300X. Late summer cloud activity was observed by ti§en"lger Donald Bei.sh, Miami, FL. He has recorded the return of the North Polar Hood veil, which reforms in late Martian summer and is indicative of the coming northern winter. Note the small NPC shining through the NPH. A possible weak blue-clearing was indicat~d by his tri-color filter observa­ tions. The apparent disk diameter was only 5". 4) 80 10 22 R, Y, G 2210 U. T. CM 61°; L 188° (Sep. 30 MD); 20 em Sch/Cass. 370X. Jeff Beish, Miami, FL. The last obserVation received for this apparition shows vague albedo features in the M. Acidalium and Aurorae S. regions. Of importance are the clouds and hazes present in early t1artian autumn. Apparent disk diameter 4~5.

The 1981 A.L.P.O. Business Meeti.ng By: Phillip W. Budine and JuHus L. Benton, Jf'.

The annual Business Meeting of the Association of Lunar and Planetary ObservePs was held on August 1 1,, 1981 in the Red Room of the Dining Hall on the campus of Kutztown State College at Kutztcwn, PA at 5:15p.m., E.D.S.T. Associate Director John E. Westfall presided and called the meeting to order. There were 22 A.L.P.O. members and others in attendance including: "Chick" Capen, Donald Parker, Jeff Beish, Norman SpePling, Alain Porter, Steve O'Meara, Richard Wend, Wini.fred Cameron, Randy Tatum, John Barnett, Gary Sydnor, RichaPd Fagin, Bill Paula, Mike Reynolds, Harold Povenmire, Paul Stegmann, Julius Benton, and Phillip Budine. Dr. Westfall presented an outline of financial matters, which were the current approximate costs for the publication of the Journal (A.L.P.O.) per issue, namely: $540.00 - printing, $505.00 - postage, $60.00 - envelopes, plus secretarial help and first class postage to U. S. and Canada. It was noted that the dues were up (as of the latest issue) to $10.00 for six issues to help cover rising costs. Dr. Westfall noted that membership currently stands at about 710 members. Next on the agenda was the location of our Annual Meeting for 1982. Dr. vlestfall stated that the only invitation was from the Astronomical League to meet jointly with them in Peoria, Illinois on July 22-24, 1982. A motion was made by Winifred Cameron to meet with the League in Peoria; it was seconded, and adopted by the members present. The floor· was opened for new business. Mike Reynolds brought up ideas concerning having a l',eteor Section ir, the A. L. P. 0. Pros and cons were discussed. Member's showed a good response to the idea, and the consensus was that the Meteor Section would be a good move for the A.L.P.O. Mr. Reynolds said that he would contact Mr. Richard Sweetsir· as a good possible Recorder for the Meteor Section. Members decided to poll the membership on the SecUon idea. Steve 0' ~lear a offered to mention the new Section in Sky and Telescope magazine if it is adopted. Phillip Budine brought up the idea of a Solar Section since several people had approached him with interest in such a Section. Discussion followed. Chick Capen mentioned that the same idea had been brought up in Tucson but was not adopted at that time. Randy Tatum expressed considerable interest in the benefits of such a Section. After much discussion, it was decided by the members present to poll the whole membership on their possible interest in such a section and also to incorporate this question with other questions, which all felt would give us information and ideas for future direction and goals for the A.L.P.O. Generally, it was felt the questionnaire should include: observer background and skills, observing interests, equipment owned by a member, and of course, his or her interest in a Meteor or Solar Section. It was stated that the form should be brief and easy to complete, and probably could be mailed with the Journal to members. Dr. Westfall said that he would design the Questionnaire Form. As there was no further business, the meeting was adjourned at 6:30 p.m.

AMATEURS AMONG THE ASTEROIDS By: J. U. Gunter (Based on paper presented at Astra Con-81 at Kutztown, PA, August 12-16, 1981) Abstract

This report presents some of the amateur astronomers who have been honored or memorialized by names. Thumbnail sketches are included for those who have made signifi­ cant contributions to astronomy. As of September 1, 1981, 2184 asteroids have been assigned permanent names by the International Astronomical Union. Nearly 25 of these, a little over 1%, have been named in honor of, or in memory of amateur astronomers. Probably a number of other asteroids are also named for amateurs, but for this report only those have been chosen whose official citations clearly identify them as amateurs.

Figure 15. Dr. Heinrich Wilhelm Matthias Oibers (1758-1840); he held Doctorates in Medicine, Surgery and Philosophy; was a Knight of the Order of Dannebrog of Denmark, the ?russian Order of the Red Eagle (3rd Class), and the Han­ overian Order of Guelph. He was also a fellow or a member of a great many scientific institutes, academies and societies all over Europe and even Boston, U.S.A. A complete list of these, as revealed in a contemporary obituary, looks formidable indeed.

1002 OLBERSIA is named in memory of Heinrich Wilhelm Matthias Olbers (1758-1840), one of the greatest amateurs of all time. Olbers was a physician who practiced general medicine in Bremen, Germany. Mainly through his efforts the city was saved from the ravages of smallpox by his introduction of vaccination about 1798, and he was praised for his untiring efforts during several devastating cholera epidemics. Later he became one of the first physicians to specialize in ophthalmology. At the age of 13 young Wilhelm became interested in astronomy, and he pursued this hobby with a passion throughout the remainder of his long life. His interest in asteroids began with 1 CERES. While tracking CERES, Olbers discovered 2 PALLAS in 1802. In the following year Karl Harding discovered 3 JUNO. The orbits of the first three asteroids suggested to Olbers that they had a common origin, possibly by explosion•of a large planet. So he searched the sky where their orbits approached one another. The result was his discovery of in 1807. Olbers was intensely interested in comets, and for more than half a century he swept the skies for them. He discovered his first comet in 1780, and his second in 1796. For this one he accurately computed the orbit, using a new method which he devised and published. His method for parabolic orbits proved far superior to others of the time, and its basic principles continue in use to this day. With another discovery in 1811, he proposed a hypothesis for comets' tails, concluding that they were streams of matter driven out from the nucleus by a "repulsive force" originating in the Sun - a hypothesis that has with­ stood the test of time. In all, he found six new comets. Olbers was one of those rare

61 persons requiring only a minimum of sleep. He seldom slept more than four hours per day, and this in part explains how he could be so productive. His best telescope was a 3.75- inch refractor. He also had a reflector and three comet seekers. He assembled the best private astronomical library in Europe. When it was sold after his death, the inventory listed 4,361 items, including just about everything ever printed on comets. 2005 HENCKE is named in memory of Karl Ludwig Hencke (1793-1866). Postmaster by day and amateur astronomer by night, Hencke reasoned that if there were four asteroids there must be more, even though none had been discovered for over two decades. In 1830, he began a systematic search, and 15 years passed before he was rewarded with success by his discovery of in 1845. Two years later he found . His discoveries sparked a search which continues to this day; and one or more new asteroids have been found in every year since 1847. 1614 GOLDSCHMIDT is named in memory of Hermann Goldschmidt (1802-1866). This German­ born artist lived in Paris. Quite by chance one evening he stopped in at the Sorbonne and heard a lecture by Professor LeVerrier on an eclipse of the Moon which was to take place that night. Goldschmidt was so fascinated that he immediately took up astronomy as a hobby. He purchased his first small telescope with proceeds from the sale of a copied portrait of Galileo. He was 50 years of age when in 1852 he discovered 21 LUTETIA, his first . During the next 10 years he discovered 13 more asteroids, a record number for any one person, amateur or professional, up to that time. For his achieve­ ments, Goldschmidt was awarded the coveted LaLande Astronomical Prize on eight occasions; and he received other honors, including the Gold Medal of the Royal Astronomical Society. 742 EDISONA is named in honor of Thomas Alva Edison (1847-1931), American inventor of the phonograph, the electric light, and much more. At age 31, Edison traveled from New Jersey to the Rocky Mountains of Wyoming to view the great solar eclipse of 1878. To shield his telescope from wind and dust, amateur Edison set it up in a hen house, together with a delicate instrument he had invented to measure coronal temperature. As totality approached, his carefully planned experiment was almost totally disrupted when the chickens came home to roost! 792 METCALFIA, and also 726 JOELLA, are named in honor of Joel Hastings Metcalf (1866-1925). Metcalf was a Unitarian minister who served pastorates in several New England towns. At the age of 12, he read a book entitled Other Worlds Than Ours. Soon afterward he observed an eclipse of the Sun, and was interested in astronomy from then onward. As a child he assembled his first telescope, using an old lens which he found in an abandoned house. Later he made much more elaborate telescopes; and with them he discovered a number of variable stars, six new comets, and 39 new asteroids. He holds the world's record for largest number of asteroids discovered by an amateur- a record which should stand forever. As an optical craftsman he was a master. He combined the skills to compute the lens curves needed for perfect performance with the manual dexterity to do the actual grinding. A 16-inch astrographic telescope which he made is still in use at Oak Ridge Observatory (formerly the Agassiz Station of Harvard College Observatory). Metcalf started the 13-inch triplet objective which is in the astrograph at Lowell Observatory. He died before it was finished, and the objective was completed by another craftsman using Metcalf's specifications. This instrument was used to make the exposures from which Clyde Tombaugh discovered Pluto in 1930. It is still used regularly, and many new asteroids have been found with it. 340 EDUARDO honors Edouard von Lade, an amateur of Geisenheim, Germany. 1040 KLUMPKEA honors the French amateur Dorothee Klumpke, who was the first woman to receive the degree of Doctor of Mathematical Sciences at the Sorbonne. 1176 LUCIDOR and 1222 TINA honor unnamed female Belgian amateurs who were friends of the discoverer, Eugtne Delporte of Uccle Observatory in Belgium. 1230 RICEIA honors Hugh Rice, an assistant at the Hayden Planetarium in New York City. For years, Rice contributed a column on observing asteroids to Popular Astronomy magazine. 1549 MIKKO honors Mikko Arthur Levander, a Finnish pastor, and father-in-law of Y. Vaisala, the Finnish astronomer who discoverd nearly 100 asteroids including this one. 1591 BAIZE honors Dr. Paul Baize, Parisian physician, amateur astronomer, and dedicated observer of double stars. 1697 KOSKENNIEMI honors Veikko Antero Koskenniemi (1885-1962), a famous poet and professor of literature at Turku University in Finland. In several poems he wrote about the stars, and he was a founding member of the Torun Ursa Society of Amateur Astronomers. 1723 KLEMOLA honors Irja Klemola, rector of a school in Turku. She was also a founding member of the Torun Ursa Society, and was its secretary for many years. She frequently participated in the minor planet program of Turku University. 1728 GOETHE LINK honors Dr. Goethe Link, eminent surgeon of Indianapolis, enthusiastic amateur astronomer, generous patron of astronomy, and donor of Goethe Link Observatory at the University of Indiana, where the planet honoring him was discovered, as well as a number of others.

62 1780 KIPPES honors Otto Kippes, pastor and instructor in religion in the parochial school of Reckendorf, Germany. An amateur astronomer in the finest sense, he established hundreds of identifications of minor planets in widely separated oppositions. 1906 NAEF honors Robert F. Naef (1907-1975), a Swiss banker and ardent amateur astronomer who spent practically all of his spare time to publish a yearly observer's almanac. 2134 DENNISPALM is named in memory of C. Dennis Palm (1945-1974), a night assistant at Palomar Observatory, an active amateur astronomer, and a dear friend to those privileged to work with him prior to his untimely death. 2136 JUGTA honors the author of this article. The acronym is derived from the initials of J. U. Gunter and those of his free bimonthly newsletter, Tonight's Asteroids. Jay has contributed over 65 columns and articles about asteroids to popular magazines, and has published over 70 regular and special issues of Tonight's Asteroids. Through his efforts thousands of amateurs, and even a few professionals, have been introduced to the pleasures of observing and studying the minor planets. Jay recently retired as a physician specializing in pathology. 2068 DANGREEN honors Daniel William Edward Green. As a high school freshman, young Green began publishing The Comet, a periodical which has flourished to become The International Comet Quarterly:--fn 1978, during 10 weeks of summer internship at the in Cambridge, MA, he applied himself so diligently that he became, at age 20, the youngest person in history to be honored by an asteroid name on the basis of meritorious achievements in astronomy. 2181 FOGELIN honors Eric Fogelin, another young man who has done a fine job as assistant to Dr. Brian G. Marsden at the Smithsonian Astrophysical Observatory. Both Dan Green and Eric Fogelin are longtime subscribers to Tonight's Asteroids, and credit this publication with arousing their interest in minor planets. 2213 MEEUS honors Jean Meeus, a name familiar to nearly every amateur astronomer. During the past three decades, Belgian amateur Meeus has made numerous contributions to the international litera­ ture on a variety of topics, chiefly planetary motions and phe­ nomena, eclipses of the Sun and Moon, occultations, celestial mechanics, comets, and asteroids, particularly the Earth-Grazing Group of minor planets. His books are standards of reference in their fields. They include Tables of the Moon and Sun (1962), Syzygies Tables (1963), Canon of Solar Eclipses (1966), Tables of Minor Planets (1963, revised with Frederick Pilcher, 1973), Canon of Lunar Eclipses (1979), and the popular Astronomical Formulae for Calculators (1979). In view of his outstanding achieve­ ments, it is difficult to think of Jean Meeus as an amateur astrono­ mer, but so he is! By profession he is a meteorologist at the Brussels Airport in Belgium. Figure 16. Jean Meeus, outstanding amateur as­ Acknowledgments tronomer and asteroid student. The portrait of Dr. Olbers is reproduced from Roth, Gunter D.: The System of Minor Planets, (1962), courtesy Faber and Faber, Ltd. London. Jean Meeus, Erps-Kwerps, Belgium, supplied the photograph of himself. The photo­ graphs of 2136 JUGTA were contributed by Ben Mayer, Los Angeles, CA. June LoGuirato, Clifton, VA assisted with the references.

References

Herget, Paul: The Names of the Minor Planets (1955 and 1968). Cincinnati Observatory. ~inor Planet Circulars, The Minor Planet Center, P. Herget, Cincinnati, OH, and B. G. Marsden, Cambridge, MA. Dictionary of Scientific Biography. Charles Scribner's Sons, New York. (Olbers). Monthly Notices of the Royal Astronomical Society, Vol. VII, pp. 27-35 (1846) and Vol. VIII, pp. 104-107 (1848). (Hencke). Ibid: Vol. XXI, pp. 129-137 (1861). (Goldschmidt). Eddy, John A.: "The Great Eclipse of 1878", Sky and Telescope, Vol. 45. June, 1973, pp. 340-34~ (Edison). Dictionary of American Biography, Charles Scribner's Sons, New York. (Metcalf). Gunter, J. U.: Tonight's Asteroids, No. 60, March-April, 1981. (Meeus).

63 Figure 17. Amateur Ben Mayer of Los Angeles, CA, worked from an ephermeris computed by Dr. Brian G. Marsden to make these photographs of 2136 JUGTA. He used a 14-inch Celestron telescope coupled with an image intensifier to record the 17th magnitude asteroid on gas sensitized Tri-X film. The two-minute exposures were spaced about one hour apart. He identified the faint object with his Viblicom, a television device invented by him for blinking photographic frames. He then "exploded" the appropriate small area of each 35 mm. negative, and made photographs of the television screen as shown above. North is up, and the retrograde motion in Capricornus is clearly demonstrated. These two pictures are from a series of four photographs of JUGTA made by Mr. Mayer on July 6, 1980. Postscript by Editor. There would appear to be four asteroids named in honor of A.L.P.O. members. Besides those which are named for Dr. Jay Gunter and Mr. Daniel Green, as mentioned in the article above, there are also ones named for Dr. Clyde Tombaugh and Mrs. Winifred Cameron, our Lunar Recorder. Of course, the two latter are hardly amateurs. When the late Dr. Joseph Ashbrook of Sky and Telescope was still alive, he would have been a fifth asteroid honoree in the A.L.PT -- Dr. Gunter's periodical, Tonight's Asteroids, is a veritable goldmine of information and charts for the observer of asteroids. His address is 1411 N. Mangum St., Durham, NC 27701. There is more information on "TA" in the next article.

THE MINOR PLANETS: AS INTERESTING AS EVER By: Alain Porter (Based on paper presented at Astro Con-81 at Kutztown, PA, August 12-16, 1981)

Introduction: Historical Context The Minor Planets Section of the A.L.P.O. was founded in the summer of 1973 as part of a surge of interest in those previously neglected members of the Solar System. During the 1960's, the glamor in professional astronomy was attached to the very remote. Quasars, pulsars, and the microwave background dominated the news. Meanwhile, among amateurs there was great interest in physical observations of the Moon and planets, which Man was about to reach out and touch for the first time. But as the 1970's brought the first phase of space exploration to a close, both groups became more and more interested in the minor planets: the professionals, because they realized there was no other way to probe the mysteries the lunar samples had both created and failed to dispel; and the amateurs, because they saw that they could indeed learn significant things with modest equipment. This interest spread rapidly, and today fluorishes. The professionals have uncovered wonders, to be sure; but amateurs have also made important contributions. They have done not only astrometry and , but pioneering occultation work. There has even been a minor planet discovery by an amateur--the first in many years. This article is meant to stimulate interest in minor planet astronomy among A.L.P.O. members by reviewing the Section's observations and work in progress, and by giving an occasional observing hint as well. Astrometry Observers who are used to knowing exactly where to find the Moon and major planets might be surprised to know that until the late 1970's, many minor planet ephemerides were rather approximate. This is one of the things that has made even visual tracking of asteroids so exciting. The Minor Planets Section publishes annual reports of all the positional observations submitted to it. The following table shows, for each year indicated, the number of observers reporting positions, the number of asteroids involved, the number of positions

64 taken, and last, but most importantly, the number of asteroids observed more than lm of Right Ascension and/or 5' of Declination away from their predicted positions.

TABLE: A.L.P.O. Minor Planets Section Astrometric Observations

Year Observers Planets Positions Large 0-C 1973-4 10 114 736 8 1975 17 227 1743 12 1976 15 233 1481 7 1977 14 298 2249 8 1978 13 323 3111 3 1979 11 313 2642 0 1980 8 267 2186 0 TOTAL 1775 15,208 38 The large residuals, shown clearly in the last column, have disappeared in recent years. This is because of improvements in the computational facilities used for the ephemerides. Perturbations due to all the major planets are now taken into account, and new observations have allowed improvement of the orbital elements. It has been three years since a residual of even +0~5, +5' has been seen. Nevertheless, observers are encouraged to track asteroids visually since, with care, it is possible to achieve an accuracy of 1' (40s of RA). Minor planets ephemerides are not uniformly that good yet. It is interesting to know which ones are better than others, and why. In this spirit, we offer the following suggestions for this type of observing program. Moderate aperture is recommended. One could eventually spot on the order of 100 asteroids with a 10-cm telescope, but most Section members have used a 15- or 20 cm.­ telescope. The most successful observer, Frederick Pilcher, has long used a Celestron 14, and has recently logged his 1000th visually observed minor planet (Pilcher 1981). A good selection of tracking charts for the beginner is the bimonthly publication Tonight's Asteroids, available for a self-addressed stamped envelope from Dr. J. U. Gunter, 1411 N. Mangum Street, Durham, NC 27701. Each issue of TA features six to eight prominent minor planets, also giving basic information on them, and reporting timely news of amateur activities in this field. To pursue more asteroids than are featured in TA, one should order a copy of the Ephemerides of Minor Planets, available from the Minor Planet Center, Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138. Also necessary is a good star atlas. This should be photographic. It is easier to interpret even a blue sensitive photograph than to have to deal with the possibility of errors and omissions in a plotted atlas. This is especially true since most of the asteroids an observer works with are near his atlas' magnitude limit. A favorite is Hans Vehrenberg's Atlas Stellarum, which covers the sky down to about photographic magnitude 14. Another choice is his Falkau Atlas, which, with a limiting magnitude of 13, is less expensive. Both are available from Sky Publishing Corporation, 49 Bay State Road, Cambridge, MA 02138. As far as observing techniques go, the two most important (other than skills in actually using the telescope) are the~ preparation and cautious measurement of the observations after they have been made. Have with you at the telescope finding charts of large, but not excessive, scale, on which you can draw the asteroid's position. After observing, measure those charts as soon as possible, always using nearby stars as reference points (for instance, if you are using a coordinate grid overlay, never line it up with the edges of the field). Spend some time figuring out the true precision of your observa­ tions. If the "x" on your chart is an arc minute across, you needn't--in fact, shouldn't-­ report the position to the nearest arc second. It would be better to find a way to make smaller "x"s. Meanwhile, once you have found an asteroid, you should make an independent measurement after it has moved, to be certain of the identification. An observer with photographic equipment has the chance to make an even more valuable contribution. If you can achieve an image scale on the order of 1'/mm, while keeping the field of view large enough to include reference stars, and keeping the focus good enough to make the star images small, your plates or film may be suitable for reduction on a measuring engine. Section members have had precise positions taken in this way published in the Minor Planet Circulars of the IAU (e.g., Watson 1981). Anyone who is suitably equippe~urged to contact the Section Recorder or the author for more details.

Photometry One of the most exciting and challenging activities of the Minor Planets Section has been the search for asteroids whose rotation is visible as a regular . If a body is very elongated, the changing surface area it presents to the observer as it turns

65 causes it to brighten and fade like a variable star. Most asteroids have very low amplitudes--0.3 magnitudes or less--but some vary by as much as a magnitude or more. Only 15-20% of the numbered asteroids have been observed photometrically, and even many of those which are known to vary do not have well defined periods. The Minor Planets Section has a photometry division which each year publishes a program of roughly a dozen asteroids which will pass through an AAVSO chart field. This approach was taken because the AAVSO charts are a combination of the best and most widely available photometric standards in the range m = 8-14. When the asteroid enters the variable star field, its brightness can be estYmated using the intermediate step method familiar to variable star observers. If, for instance, the asteroid is fainter than a star marked 9.0, and brighter than one marked 9.4, but closer in brightness to the fainter star, its magnitude would be recorded as 9.3. Independent estimates--and we stress the adjective; one must work not to be influenced by what one has already seen--taken every 15 minutes for as long as possible will show whether or not the asteroid varies visibly. If it does not, it can be abandoned after the week or so it spends in the AAVSO field. If it does, an extended ephemeris and new comparison sequences can be prepared to permit more light curves to be made. For many years, all the known periods of rotation among asteroids were short--less than a day. Since in most light curves caused by the rotation of an elongated object, there are two maxima and two minima per cycle, such variations can be spotted in a matter of hours. Now, however, several very slow rotators are known. Thus, 182 Elsa, the slowest, has a period of 80 hours. The observer should hence not be discouraged if he sees no variation on a single night. He may find the asteroid at a different magnitude a night or two later. Two light curves made by Section members are shown here. The first, Figure 18, of 433 Eros, a famous object, was made during the favorable 1975 apparition by pgotometry coordinator Derek Wallentinsen. Eros is a control experiment: its period, 5 16m13s, has been known very precisely for many years. It is in opposition again this winter, and passes through the field of U Persei. An ephemeris is given, showing the asteroid's separation in arc minutes and position angle in degrees from the variable star for each date. Eros' visual magnitude will be 10.6, and the Moon will be near Last Quarter. These conditions are relatively quite good.

TABLE: Ephemeris of 433 Eros Relative to U Persei

1981 UT Oh Separation (I) Position Angle ( 0) November 18 25 67 19 7 48 20 12 260 21 30 250 In the other extreme, the only known light curve of 535 Montague is the one shown here as Figure 19. The observer, Gerry Samolyk, is an experienced eclipsing binary watcher. This light curve is very suggestive of a period of 8 hours, but it is still awaiting confirmation. As in astronometry, there is the opportunity for an observer with advanced equip­ ment to make a greater contribution. A photoelectric photometer allows study of varia­ tions of 0.01 magnitudes, not just 0.1 magnitudes. This opens an entirely new realm of physics: one can detect spots and discoloration on an asteroid, as well as irregularities of shape. Some Section members have begun this work, and have gone on to publish their own work in Icarus. Those who can and want to do photoelectric photometry of minor planets should contact the author, and consider joining the group International Amateur/ Professional Photoelectric Photometry (write Russell M. Genet, Fairborn Observatory, 1247 Folk Road, Fairborn, OH 45324). The photometry division has lost a number of observers recently, and needs new blood to continue doing useful work. All are encouraged to attempt a light curve of 433 Eros in November, and then to contact the author with their results and interest. (Two U Per charts, #015254 b9 and d, are available for 50¢ from AAVSO, 187 Concord Ave., Cambridge, MA 02138.)

Occultations The value of observing occultations of stars by asteroids was proven dramatically in 1975, when 4th magnitude Kappa Geminorum cast the shadow of 433 Eros across the Hudson Valley and central Connecticut. Although the exact shadow path was not predicted until just 3 hours before the event, 10 observers were able to get into position in time. The result of their observations was a silhouette of the minor planet, shown here in a pre­ viously unpublished chart (Figure 20) by the author. The horizontal axis represents distance across the shadow path; and the vertical axis distance along it, as measured by eclipse duration. Two uncertain observations which disagree with the other seven are

66 mv

7.3 • • •

7.5 • • •

7.7

7.9 • . .. • 433 Eros January 24, 1975 • D. Wa11entinsen • 11 em ref1. 8.1 • • • •

2 3 4 5 Figure 18. Observed light-curve of Minor Planet 433 Eros. See text on page 66 of article by Alain Porter. There are two maxima and two minima in the period of rotation of 5 hrs., 16 mins.

535 Montague January 22, 1977 G. Samo1yk 32 em ref1.

12.8 • • • • •• •• • • • • • • 13.0 • • • •

2 3 4 5

Figure 19. Observed light-curve of Minor Planet 535 Montague. See text on page 66. Further observations are needed to determine the period of variability.

plotted as an error bar and an open circle. The tenth observer did not report an eclipse duration. Still, there is a clear asymmetry in the silhouette, which is much flatter on the western side than on the east. An independent analysis by O'Leary et al. (1976) con­ firms the shape, and gives a length about 12% greater. Several more occultations of stars by asteroids were observed during the 1970's, yielding an even more astonishing result: secondary occultations, which have been attri­ buted to tiny satellites orbiting the already known asteroids. One of these events was observed independently by 2 visual observers and 1 photoelectric observer (Dunham 1978, McMahon 1978). The existence of the satellites is not universally accepted (e.g. Reitsema 1979) since the 2 photoelectrically documented occultations took place at very low altitudes, and there have been no more reports since 1978. But the possibility of discovering a new Solar System body should certainly attract A.L.P.O. members to this kind of work. These occultations are actually common, but until recently they were almost never observed because they could not be predicted. But as we have shown, the ephemerides of the minor planets are now greatly improved, to the extent that the Occultation Newsletter of the International Occultation Timing Association (IOTA) publishes shadow path maps

67 0

• 15 km Figure 20 • silhouette of 433 Eros from occultation of

T ~ Geminorum I • January 24, 1975

I 10

I' • •I •

•

5

•

-5 0 5 km regularly. The Minor Planets Section has deferred to IOTA in this area because they can tap their long experience in predicting grazing lunar occultations of stars. Those wishing to keep current on the minor planet occultation predictions should subscribe to the ON, available for $7 per year from John D. Phelps, Jr., PO Box 596, Tinley Park, IL 6044~ We are eager to share in the observations because of the astonishing new dimension they add to our knowledge of the minor planets.

Search and Recovery A program the Section would like to see started is amateur search for new and interesting returning asteroids. Such work has traditionally been the preserve of observa­ tories with large Schmidt cameras, but three recent developments leads us to believe that there may be room for amateur contributions: 1) The marketing of small Schmidt cameras, e.g., by Celestron, which some amateurs can afford. 2) The discovery of 2090 Mizuho by an amateur in 1978 (Gunter 1980). 3) Increasingly serious budget cuts at many major observatories. The large Schmidts cannot be looking everywhere all the time. A well-equipped, disciplined observer who can reach photographic magnitude 14 or fainter can discover a new asteroid. It has been done. Hodgson (1981) has suggested that in medium or high latitudes, a search of subpolar regions of the sky around the time of summer solstice might reveal minor planets inside the Earth's orbit. Since the discovery of the Aten objects, which have semi-major axes less than one , this idea does not appear as farfetched as it might have before. This is an advanced observing program that would be tailored to an individual's powers and interests. Candidates should contact the Section Recorder for further discussion.

68 Conclusion Minor planet astronomy is becoming an increasingly rewarding pursuit for both pro­ fessional and amateur astronomers, and the Minor Planets Section invites all A.L.P.O. members to participate. General information and subscriptions to the Section's Minor Planet Bulletin ($7 per year in the U.S.A., Canada, and Mexico; $7.50 per year surface, or $9 air, mail elsewhere on Earth; institutional rates $8 per year; $2 extra for overseas airmail) are available from Recorder Richard G. Hodgson, Dordt College, Sioux Center, IA 51250. Information and predictions for photometry, plus observing forms, are available for a self-addressed, stamped envelope from photometry coordinator Alain Porter, Department of Astronomy, California Institute of Technology, Pasadena, CA 91125.

References 1. Dunham, David W. ( 1978) "Satellite of Minor Planet 532 Herculina Discovered During Occultation", MPB, 6, 2, 13-4. 2. Gunter, J. U. --(-1980) Tonight's Asteroids, 54 1. 3. Hodgson, Richard G. (1975) "General Reportof Observations by the A.L.P.O. Minor Planets Section for the Years 1973 and 1974" MPB, 2, 4, 34-40 [1973-4]. 4. McMahon, James H. ( 1978) "The Discovery of asatellite of an Asteroid", MPB, ~. 2' 14-7. 5. O'Leary, BrianT., et al. (1976) "The Occultation of 1< Geminorum by Eros", Icarus, 28, 133. 6. Pilcher, Frederick (1977) "General Report of Position Observations by the A.L.P.O. Minor Planets Section for the Year 1976", MPB, 5, 1, 1-6 [1976]. 7. Pilcher, Frederick (1978) MPB, 6, l, l-1-0--[1977]. 8. Pilcher, Frederick (1979) MPB, 7, l, l-7 [1978]. 9. Pilcher, Frederick (1980) MPB, 7, 4, 21-6 [1979]. 10. Pilcher, Frederick (1981) MPB, 8, 3, 22-7 [1980]. 11. Pilcher, Frederick (1981) "Seeing 1000 Tiny Planets", Sky and Telescope, _22, 6, 560-2. 12. Rei tsema, Harold J. ( 1979 ) Science, 205, 185. 13. Watson, William et al. ( 1981) Minor Planet Circulars, 5829.

COMET WEST 1976 VI: OBSERVATIONS OF THE GREAT COMET OF 1976 By: Derek Wallentinsen, A.L.P.O. Assistant Comets Recorder and James-Mims Observatory Abstract Observations of this brilliant comet by A.L.P.O. Comets Section participants from November, 1975 to August, 1976 are discussed. General observations are reviewed; and aspects of Comet West's tail, coma, and nuclei are described. Daylight observations during the period around perihelion passage in late February, 1976 are related. The heterogeneity of the body of visual coma diameter determinations makesimpossible the practical corre­ lation of diameter and solar distance. Longer tails call for more accurate calculation of tail lengths, and future A.L.P.O. comet ephemerides should include the cometary solar phase angle. I. Introduction Comet West displayed a rich and fully rewarding variety of phenomena for all who observed it in 1976. Its brightness and spectacular appearance justified the pre-dawn outing for casual observers, amateurs, and photographers, while the break-up of its nucleus and complex tail structure delighted cometary astrophysicists. Certainly Comet West was a superlative object which will long remain in the memory of those who saw it. Some have called it the finest comet yet seen this century. It was one of the relative handful of comets to be observed in broad daylight. Truly a rare object! Almost half a thousand observations were submitted to the A.L.P.O. Comets Section describing the full range of Comet West's physiology. In this paper I shall synopsize the many notes, present results of an analysis of visual magnitude estimates, and discuss the relation of the observations to physical phenomena in Comet West's nucleus. Only limited illustrative coverage will be given here. The reader is referred to the many fine photographic reports that have already appeared for an extensive pictorial account of the apparition (Anonymous, 1976a, b; Haas, 1976a, b, c; Sekanina, 1976; Haas, 1977). II. The Apparition: General Visual Observations a. Early Observations The earliest observations reported to the Comets Section were those of Leo Boethin on November 25 and 28 and December 4 and 5, 1975, less than a month after Richard West's discovery on November 5. On all four dates the comet was just visible in a 20-cm reflector with a very diffuse tailless coma estimated at 4' and then 8' in dia~eter, and 12.7 magni­ tude in brightness. The solar distance (r) and geocentric distance (6) were 2.08 and 2.39 Astronomical Units respectively on November 24.

69 Because the comet was relatively faint and below -30° declination through late January (hence poorly placed for Northern Hemisphere observers, who constitute the majority of A.L.P.O. members), and afterwards only 25 degrees or less from the Sun until March, very few observations were made before perihelion in late February (see Table I, Ephemeris and Elements). Albert Jones of Nelson, New Zealand made the only other 1975 observations, reporting a diffuse Comet West as magnitude 9.5 and 8.7 on December 23 and 30 respectively, with a 32-cm reflector. Another "southerner," Gregg Thompson (see Table II, Participating Observers), saw the comet brighten through 7th magnitude in late January, and observed a tail with the comet at low altitude in the evening sky. Mr. Thompson also reported observations on five days in mid-February: between the 13th and the 19th the comet increased its light by 3 magnitudes to attain first magnitude on the latter date and presented a thin and faint two-degree tail in twilight. b. Daylight Observations From February 15 to March 3, 1976 Comet West was less than 18° from the Sun. Yet a brilliance in the negative magnitudes more than compensated for the small elongation, and it became one of the very few comets visible in full daylight. Seven reports of daylight observations by four observers were received for February 25 and 27. There were an additional eleven reports from February 21 through 29 in very bright dusk or dawn skies, and one report of tracking the comet into daylight as late as March 7. Charles Townsend saw the comet at only 3-3/4° altitude above the Pacific Ocean 23 minutes after sunset on February 22.09 U.T. It was "tear drop shape" in appearance, 25' long and estimated as 1~0 in 7x50 binoculars. Joseph Marcus sighted Comet West 22 hours later (23.01) in a 15-cm reflector at 48x, when it was judged to be -lm or brighter by memorized comparison with Mercury, Venus, and Jupiter. It was only 3/4' in diameter, with the "bare beginnings" of a tail less than l' long. This was described as "a short central spike and parabolic envelope" in the antisolar direction. A search five hours earlier in daylight with a sodium D-line interference filter in a fairly transparent sky had failed to reveal the comet. Later the same day (February 23.95), John E.Bortle sighted Comet West just after sundown in 10x50 binoculars, and using the same comparison method as Marcus, estimated the comet to have a total magnitude of -1.6. The tail configuration was again described as parabolic with an "extremely intense, dense, brilliant condensation," about 30" in diameter, white in color and located at the leading edge of the parabolic tail, itself some 20-30 arc-minutes long. A day afterwards (February 24.94), Peter L. Collins at Harvard College Observatorili (HCO) saw the comet in bright dusk ten minutes after sunset with a 6-cm aperture at -0.5. It was nearly stellar in the finder and looked elliptical in a 23-cm refractor at 100x, "very much like Mercury." Bortle, observing from Storm­ ville, New York at the same time, estimated 1976 VI at -1~9 in his 10x50s; and the "comet was eas(il)y visible when first seen and must surely have been visible well before sunset in a modest telescope." The same evening (February 25.09), James H. McMahon, George F. Stillwell, and Anita McConnell, observing from the California desert, saw Comet West in bright twilight for ten minutes before it set behind the local mountains, using 7x35 and 7x50 binoculars. Even under these conditions, a tail about 1/2 degree in length was visible. Townsend was watching at the same time with 7x35's and saw a 3/4° tail with the parabolic envelope in evidence. Total magnitude was about -1. February 25.2, 1976 was the time of perihelion passage. The 25th resulted in no less than six of the seven daylight observations. Stephen O'Meara was the first to see Comet West in broad daylight at a few minutes past noon local time (February 25.72 U.T.) using the 23-cm Clark refractor at the HCO. The rough magnitude estimate was -2: the slightly elongated but tailless coma was very condensed and had a "planetary appearance." Collins, observing with O'Meara (25.73), saw the comet in the 6-cm finder of the Clark telescope; and it was "readily visible when centered, especially with the help of a pink filter." Later that afternoon (25.81, 25.92), O'Meara was able to pick up Comet West with 7x35's; in the 23-cm a one degree bifurcated tail in position angle (PA) 100° and a coma with two jets pointing due west (the parabolic edges noted previously) were visible. Dennis Milon (a third observer at the HCO) saw the comet at sunset (February 25.93) in 7x35's and described a white parabolic head in the Clark refractor. Bortle found it in a 32-cm reflector about one hour before sunset. In this instrument it was "a brilliant almost stellar object 10"-15" in diameter, white in color, and like a planet in poor seeing in sharpness and solidity." There was a faint parabolic fan in the antisolar direction with bright jets or swept back "wings" at PA's 150° and 330°. The tail appeared as long as 30'-40' at sunset, quite straight and narrow. About 35 minutes after acquisition in the 32-cm the comet was easy to find in 10x50's by sweeping the region only 7° elongation from the Sun (mag. -3). The appearance in binoculars was "brilliant, like the planet Venus in the daytime but with a bright 15' tail!" His ultimate observation came seven minutes before sundown when he detected the comet with the unaided eye--"an incredible sight!"--again similar to Venus though not so bright. That evening (February 26.09), Townsend saw the comet as "easily visible with the naked eye at mag. -2. The tail was washed out by haze and skyglow."

70 Chet Patton in Michigan saw Comet West in the morning sky (February 27.50) as -0~2. Bortle observed it around local noon (27.72) with a 32-cm reflector and 15x80 binoculars-­ the final daytime sighting. A small, very bright, dense nucleus 10" in diameter with slightly diffuse edges, white in color with a tinge of orange or red was seen with the telescope stopped down to 25 em. The nucleus was surrounded by a 30"-60" diffuse halo. A stubby 2'-3' tail was occasionally visible in the binoculars. Bortle estimated the magnitude as -2.4 by direct comparison with Mercury and Venus. Observing with 10x50's later in the day (27.97), Leonard Matuszewski saw Comet West with a strongly condensed 10' coma, 1-1/2 degrees long, bright, narrow tail in PA 25°, and a total magnitude of -2.5 Comet West was visible to the naked eye in bright evening twilight at 2-1/2 degrees altitude. There were no observations on the 28th. Collins used Mercury to determine Comet West's magnitude as -1.5 (February 29.44) in 7x35's. Bortle observed until sunrise at 11:31 U.T. One degree of straight narrow tail was seen with the naked eye after the comet's head rose in twilight. The parabolic ''wings" were observable in the 32-cm, coming from the sides of an extremely brilliant, small and highly condensed area 20"- 30" across. The comet (at magnitude -1.3) was lost to view at sunrise when cirrus clouds intervened. Milon saw the comet in dawn twilight at Duxbury Beach, Massachusetts (29.47). A parabolic tail structure was revealed with a 15-cm reflector. In his binoculars it was definitely fainter than Venus. c. Postperihelion Observations Comet West displayed an incredible wealth of phenomena in the morning skies of March, 1976. The elongation from the Sun increased rapidly until by midmonth the comet could be readily observed in darkness. Wolfgang M~hle, Stuttgart, Germany, observed the comet with the unaided eye on March 1.22 (magnitude -1.5). The tail was 3-1/2 degrees in length, golden-yellow in color, and conspicuous, despite some cloudiness and twilight. The structure and length of the tail grew daily as the comet moved away from the Sun. Rainer Lukas in Berlin reported a 10°-15° tail on March 3.20 in 20x70's. The author watched the broad dust tail rise for twenty minutes. It curved to the north with a second band diverging from the main tail at an angle of six degrees. With the main tail, the width at the end was 4 to 5 degrees, with 10 degrees of the bright, very spectacular appendage visible with the eye and 13-14 degrees with 7x35's (March 3.52). R. B. Minton saw an extraordinary length of tail--20- 25 degrees with the eye, the latter measure corresponding to 47 million km true length. With binoculars and naked eye Marvin J. Mayo of Agoura, California noted a fan-shaped tail at PA 310°, and Townsend saw a 10° tail of strong curvature and varied structure with binoculars (both on March 4.55). The coma during the first few days of March was small (a few arc-minutes), very condensed and generally white, though Jeffrey Sandel described a burnt-orange color. The comet was still very bright: I called it -0~4 with the unaided eye after extinction corrections (March 3.52). On the morning of the 5th Muhle reported 7° of tail (8x35's) and a double, non­ stellar nucleus (18-cm refractor, 260x), perhaps the first observation of nuclear multiplicity of the apparition (March 5.22). Daniel Louderback observed Comet West through red, yellow, and blue filters and found that the comet's overall hue was yellowish, while the coma-head was relatively blue (5.58). Raw magnitude estimates around this time varied widely--some wildly--ranging from -4 to +2.5, the consensus value being closer to the latter. Estimates were affected by observing conditions of twilight, weather, altitude/extinction, instruments, casual method, and inexperience-with such a large, bright comet. Conrad Kussner, Cliff Perkall, and Rick Lasher observed a 10°-12° tail in binoculars and a 4°-5° tail w~th the naked eye (6.44). The color of the tail was white; two days earlier they had noticed an orange tint. March 7, 1976 was a morning on which many were active observing Comet West. For this single date, 18 reports were received. Bortle (7.41) reported a complex 25° long by 10° wide tail, and he described the entire comet as "an incredible object in binoculars!" Collins observed two principal components of the 5° tail at PA 300° (gas) and 320° (dust), while Robert E. Slobins characterized the tail as pearly-white and forked (7.42, 7.43). Gary Kronk, Edwardsville, Illinois, saw a 15° tail in PA 300° and estimated total magni­ tude at 1.8 with the eye (March 7.47). Mayo found a bright dust tail with streamers fanning out to the north, 10° in length in PA 295°, coming from a very stellar coma of DC=S (degree of condensation on a scale of O=diffuse to 10=stellar). Tim Robertson also saw a very condensed coma in binoculars; and he described the tail as 6° long, curved near the coma, and blue in color with a dark streak in it (March 7.55). Colors on the 7th were described as yellow tail (Charles Hughes), yellow-orange coma (Doug Smith), and bluish tail and coma (Claude McEldery), while Matuszewski observed the nuclear condensation to be bluish. Townsend notes tracking the comet into broad daylight on this date, using a 13- cm catadioptric instrument at 25x.

71 O'Meara and Bortle, observing simultaneously from different locations, independently reported two nuclei on March 8.41 UT. Both components were in a 10" condensation at the focus of the parabolic envelope, which Bortle described as "very intense and brilliant, like a planet with soft edges." A very narrow tail spine about 15' long was seen in PA 308°; where this joined nucleas A Bortle discerned a very narrow dark lane--"the shadow of the nucleus"--about 1° long in PA 303°. On this same data, Morris estimated the comet's total magnitude at 1.7 in 8x52 binoculars. Robert Clyde, Streetsboro, Ohio, called the fan tail pearl-colored (8.46). Many observers saw two tails, with some reporting as many as five in early March. Comet West was a rewarding object with all apertures and magnifications--especially true as the nuclear fragmentation developed throughout the month. This feature was now an object of scrutiny, with numerous reports of two or more nuclei. (Unfortunately, there were also some observers who confused the bright central condensation (cc) with the actual nucleus.) Charles F. Capen, using filters, determined nuclear color to be neutral on the 9th; McEldery observed two fragments on the 11th in a 32-cm Cassegrain at 300x, while O'Meara, Bortle, and Capen saw four parts on the 11th, 12th, and 15th respectively. However, Sandel (15-cm at 220x, March 11.44) saw only a 6" cc, and Kenneth Delano (12th) recorded only a sharply defined cc in a 20-cm catadioptric at 127 and 207x. Alain Porter, Narragansett, Rhode Island, observing on the 12th with a 10-cm refractor at 83x, noted a blue-green coma "and some nuclear detail suspected," but no special detail was recorded. Matuszewski saw a graininess in the 5' coma using 10x50's on March 14. Russell Maag saw a tail that was greater than go in length and approximately 2° wide at its end on March 13.50. There was a marked bifurcation of the ionized portion and the dust portion. Tail color was adjudged to be pearly-white. In a 20-cm reflector Maag estimated the magnitude as 2.5-2.6. Other total magnitude observations during the period March 9-14 ranged from 0.9 to 3.5 with the "average" around 2. The Moon was full on March 16 (see Table III, Lunar Phases); and consequently some estimates of the tail length, magnitudes, and other cometary features were affected. I observed 5°-6° of dust tail with 7x35's and 2-1/2 degrees with the eye on March 15.51, and estimated the total magnitude (eye) at 1.8. O'Hara saw two tails 3° long and noted difficulty in seeing detail because of moonlight. Measured coma diameter was very small-- 40 to 45 seconds of arc. His magnitude estimate was 3.3 with 7x35's (15.52). Mayo, who had been reporting 20° tails, saw only 3° of tail on March 16.55 in FA's 285°-315°. McEldery made visual positional measurements by using a R.A. drift-declination drive technique. The 0-C residuals of four observations on March 11-26 from the ephemeris were small, variable, and probably within the error of the method, though he remarked that the "comet seems to be north and east of the predicted position." The only trend was in the R.A. residuals--placing Comet West about 0~2 east of the ephemeris. John D. Sabia, Scranton, Pennsylvania, detected no color in 1976 VI's 2-l/4 degree t?il in a 15-cm reflector on the 18th, though the coma, which had an elongated cc, was a "blue-white hue." Delano made no estimates of tail or coma because of moonlight and twi­ light. Under mediocre conditions on March 19.18, Marco Cavagna* noted a "bright filiform tail" 30' long in PA 285° in 20x70's. Comet West's total magnitude was 3.7 in 10x50 binoculars on March 20.40 to Bortle, who saw four nuclei in his 32-cm reflector. O'Hara reported a 3' coma on the 20th in his 6-cm refractor. Matuszewski called the 5° tail bluish (10x50's) on March 20, and on the 21st, bluish-magenta. Porter's remarks for March 22 (using 7x35's) are: "The primary tail (6°, PA 292°) consisted of a quite narrow central core, like a spike, inside a gradually spreading (although it appeared tapering through the 15-cm) fainter envelope. A distinct second, perhaps dust tail was observed coming out of the WSW side of the coma, but immediately turning back parallel to the first tail." On March 23 David D. Meisel at Geneseo, New York estimated Comet West's total magnitude as 4.1 using 7x50's, the Bobrovnikoff method, and Alpha, Delta,.and Epsilon Delphini as comparison stars. Capen, continuing his filter observations \Harch 24.52), saw a "short, frn-shaped tail" that "looked mostly white" and extended to a distance of 4-112 degrees. Most of Bortle's observations during this part of March discerned three nuclei. These were surrounded by an elliptical cc of a few tenths of an arc-minute in extent. A ''straight, fairly broad, diffuse tail spine" from 10 to 15 minutes long was located behind the coma, generally in the same PA as the first tail. A possible "dark lane" to the south of the spine was noted on the 24th. The coma was circular, sometimes with a hint of that parabolic envelope noted by many observers. The DC ranged from 5 to 8. The comet faded one magnitude in the last eleven days of March. O'Meara then observed three nuclei, though by April he could see only two. McEldery, observing on the 26th from urban surroundings, "looked in earnest" to detect any trace of nuclei. He searched with a 20-cm Cassegrain at 130 and 264 powers, but all he found was a brightening in the central coma and an elongation in PA 290°. On the next morning, Porter noted only a "slight hint of a nucleus" and some mottling in a bluish, slightly elongated 3' coma in a

*Incorrectly given as Cavagna Marco in Wallentinsen (1978).

72 15-cm aperture. Mayo, in good conditions near Agoura, saw a 12-degree tail in his 10x50's on the 29th. It occupied a swath of 40° in PA--from 270 to 310 degrees, and was clearly visible to the naked eye. One of the last sightings of Comet West by the unaided eye was Patton's on April 2. He estimated it with the eye as 5~9. The final such observation was by O'Meara on April 15, when it was barely visible to him in clear skies. After the events of March, the rest of the apparition was almost anticlimactic. The comet faded slowly but steadily throughout April, but was still a widely observed and well observed object. On the lst, it was about fifth magnitude; and on the 30th, about seventh. Most of those who reported a tail estimated its length as several degrees. O'Hara saw a 2° "colorless and ill-defined (tail); three streamers apparent: central one brightest, one on each side marking north and south boundaries, which are fainter (7x35's, April 4.43). 11 Mayo, Wallentinsen, and Sabia supplied similar descriptions of northwards curving tails. The spine noted in March was also frequently reported. O'Heara thought it was widening on April 7.40. Color, if given, was "bluish." On May 1.09, Cavagna, 30 km north of Milan, estimated Comet West's magnitude as 8.0 in 20x70 binoculars. Christopher Stephan saw a bright coma and a cometary head that looked like an unresolved globular cluster (8.29), and a 1/2 degree tail in PA 290°. Jones from New Zealand saw a gradually brighter central strong condensation on Hay 10th, a broad tail extending to 30', and a thirteenth-magnitude nucleus. The comet was increasingly diffuse with the tail (if any was reported) difficult to distinguish from the coma. However, a one degree tail was seen by Morris as late as May 24th. On the 25th Patton gave the total magnitude as 8.7 in a 15-cm reflector, while Bortle saw it as 7~2 on the 24th in much smaller 10x50 binoculars. A month later (June 27) Bortle estimated the 17' coma with a 15' tail as 8~1 and the degree of condensa­ tion as 3. Morris was also describing the coma as large and diffuse during June and July. He and Jones both noted a slight coma condensation during July. Reports dwindled sharply during the last two months of Comet West's visibility in small telescopes (July-August). Morris' last observation (August 3.18) was with a 15-cm Newtonian at 24x: The comet (mag. 9.3) was very difficult to see. The final sighting was by the indefatigable Bortle: August 25.09, 1976, 11~0, 2'.5, DC=O. Comet West was "at the limit of detection, extremely faint and difficult." On the 30th, his search for it was unsuccessful. d. Nuclei Before perihelion, the nucleus of Comet West exhibited nothing unusual to A.L.P.O. observers. Gregg Thompson was the only one specifically to report an observation of the nucleus during this time period. On February 13.31, he saw a "very faint yellow nucleus" in a 20-cm reflector. (See Table IV for observations of the nucleus.) Bortle, observing through perihelion on 23, 25,and 27 February, saw an "extremely intense ... almost stellar" central or nuclear condensation in bright twilight and broad daylight from 10 to 30 arc-seconds in diameter. Using the 30-cm refractor of the University Observatory of T~bingen at 450x, M~hle discerned a starlike nucleus on March 2.22, embedded in a para­ bolic front. Others were reporting a tiny though not stellar nuclear condensation. Sandel (March 4.46) reported a 3" feature while Minton (March 4.53) observed an elonga­ tion in the 9" cc perpendicular to the PA of the tail. M;;hle made the initial sighting of a multiple nucleus on March 5.22: "double nucleus (not starlike)." Fifteen minutes later, two other German observers at the Hoher List Observatory recorded a secondary nucleus (Marsden, 1976b). After this, observations of second, third, and fourth nuclei were relatively commonplace. However, not everybody saw two or more nuclei. A 5x7-second elongation was des­ cribed by Minton (March 5.52), who, using a 15-cm aperture, never reported more than a 3"x6" condensation. Morris found only a "false nucleus" and Sandel only a tiny cc. Many others confused this feature and other phases of the comet's prominent central condensation for the starlike nuclei, especially inexperienced observers using low powers of magnification and/or small apertures. In the first two weeks of March there were independent discoveries of the unusual nature of Comet West's nucleus. Townsend observed two stubby, elliptically-shaped nuclear subcomponents "in the shape of an off_set T," almost but not quite tangent within a 6" circle on the morning of March 7 (-12h UT), using a 13-cm Maksutov at 213x, and strongly suspected nuclear splitting to be in progress. Bortle found two nuclei on Harch 8.41, the second nucleus perhaps 5" distant in PA 340° and one magnitude fainter. He named these fragments A and B. These alphabetic designations were quickly adopted by the astronomical community (Marsden, 1976b). At the same time, O'Heara also detected two (PA 350°, separation 1~5, 1/2 magnitude difference), while Capen at Flagstaff noted a "possible multiple structure in the nucleus" in an elongated coma normal to the tail axis, using 20x80 binoculars (March 8.53).

73 Using the Clark refractor of HCO at 100x, O'Meara saw four nuclear parts on March 11.39. Other observations of fourfold nuclear separation were by Sabia on 12.41 in bright twilight (also with a 23-cm refractor); by Helen Lines, Phoenix, in a 40-cm reflector on March 14; and by Capen on March 15, using the Lowell Observatory 50-cm refractor at 170x. Bortle found that advancing bright twilight on the morning of the 12th revealed four nuclei out of a pale green cc 5" across. Townsend also saw nuclear components under similar circumstances on the 7th. Numerous others who were not members of the A.L.P.O. also observed and photographed nuclear fragments in early March (Marsden, 1976b and IAU Circulars et seq.). Bortleestimated themagnitude of nucleus A as 8.0 on March 14.40, B (8" away in PA-330°) as 10~0, and D (3", 345°) as 10~5. Nucleus C was not seen through his 32-cm reflector, though he did observe it on the 18th and 20th. However, it was on its way out. Only three nuclei were visible to Bortle on March 22. O'Meara reported "3 nuclei; nucleus C (has) disappeared" on March 23.38 with the Clark. Sabia as well saw only three fragments on March 24.40, while on the 26th he found three nuclei, one of which was "not starlike but nebulous." The last anyone saw of nucleus C visually was on March 27.4 (Marsden, 1976c), when it was five magnitudes fainter than A.* Color of the nucleus, when given, was blue-white, as when Capen observed it with 20x80's on March 24.52. He saw two parts. Throughout April, most observers reported only two nuclei. However, M~hle managed to see a triple nucleus on April 1.16; and Bortle reported A, B, and D components-­ though not necessarily all three on every occasion--throughout April, May, June, and July with his 32-cm reflector. On April 13 he called them 12~8, 14~0, and 13~4, res­ pectively. Sabia and O'Meara reported two nuclei; the latter estimated the separation as 10" on April 7.40 and 8.31. The ever fainter nuclei were followed by fewer and fewer people. On May 9.23 Milon reported three nuclear subcomponents, with one of them only intermittently visible, in a 15-cm telescope. Bortle submitted the latest report of visibility of multiple, or even any, nuclei: "July 19.10 ... Nuclei A, B, D all suggested. Mag. 14.9."

e. Coma

The coma of Comet West was a strong contributor to its spectacular appearance. Very diffuse towards the beginning and end of its apparition, the coma was very sharply defined and very condensed throughout the period of the greatest brightness, February through April. The late 1975 observations of Boethin and Jones were of a very diffuse coma only. Through January and February, 1976 the comet apparently developed a central condensation (cc). Very few observations were reported during this time. Prominent features which became evident before perihelion passage on February 25 were the parabolic coma-tail envelope of Comet West's head and the very highly condensed cc described as either like a planetary disk or stellar, depending on instrument and magnification. "Comet virtually stellar in finder. Maybe a slight suggestion of a tail," was Peter Collins' comment on the daylight observation of February 25.73. O'Meara (25.81) called the coma crescent-shaped and 10' across at its greatest extent. It had a white parabolic head, according to Milon at the same time and through the same telescope. The comet maintained much the same appearance in early March. Sandel remarked on its "shield-like appearance" and saw a burnt-orange color with a bright spine several arc­ minutes long directly below the coma's cc (3.46), while Minton found a round, well condensed and bright coma with an 18" cc (March 3.54). There was "no structure in (the) coma like (that of Comet) Bennett", he noted. Tim Robertson (4.56) said the coma was "very stellar and bright; very beautiful comet." Yet another term for the coma's form-­ fan-shaped--was used by Marvin Mayo (4.55). The coma was almost parabolic and displayed a false nucleus to Morris (March 6.46). He measured the width of the head as 2'-3' and noted the comet's color as "dirty white." He and others saw no distinction between the tails and the coma. The coma was the by now familiar parabolic envelope to Bortle (7.41), some 3-4 minutes wide with an extremely intense 1' condensation located near its leading edge, similar to Comet Bennett 1970 II in appearance. In his 32-cm reflector he saw a "very solid-looking condensation about 20" in diameter". Delano observed the same 1' condensation in a 3' coma using an 8-cm Ouestar at 48x (7.42). There were many other descriptions on the busy March 7th: "Almost a little egg­ shaped," (Charles Hughes, 20-cm, Flat Rock, MI); "Very condensed, almost star-like, but not quite. Slight fuzz surrounding it. Central condensation ... a bright blob," (Daniel Costanzo, 7x50's, Leesburg, VA); "Large bright coma surrounding nucleus. Overwhelming in its brightness and size," (McEldery, 15-cm reflector); "Ouite bright, appears star­ like with the naked eye; appears bilaterally symmetrical with 7x35's; no jets or streamers visible; no visible shells," (O'Hara); "Also observed in the head region of the *C showed faintly on a March 28 photograph taken from New Mexico (Sekanina, 1976). (text continued on page 78) 74 TABLE 1. EPHEMERIS AND ELEMENTS FOR COMET WEST 1976 VI DATE E.T. R.A. (1950) Dec. ('> r Elong. h m AU AU 1975 Nov 24 20 24. 1 -39 27 2.391 2.083 60 Dec 4 20 32.0 -38 28 2.355 1.920 52 14 20 42.6 -37 23 2.297 l. 750 45 24 20 55.9 -36 12 2.213 1 .573 39 1976 Jan 3 21 11.8 -34 50 2.101 1.386 33

13 21 30.6 -33 11 1. 959 1.189 28 23 21 52.7 -31 04 1. 784 0.978 25 Feb 2 22 18.7 -28 06 1.569 0.747 22 12 22 48.9 -23 18 1. 303 0.492 19 17 23 03.8 -19 19 1.141 0.356 17

22 23 11. 1 -12 50 0.954 0.232 14 27 22 46.2 -03 01 0.807 0.209 6 Mar 3 22 04.0 +04 10 0.810 0.318 17 8 21 36.3 +07 40 0.872 0.455 27 13 21 19.4 +09 37 0.941 0.587 35

18 21 08.4 +10 56 1.003 0.713 42 23 21 00.4 +11 59 1.056 0.833 48 Apr 2 20 48.1 +13 42 1.137 1 .056 59 12 20 36.4 +15 12 1.190 1 .262 70 22 20 22.8 +16 29 1.226 1 .455 81

May 2 20 06.1 +17 30 1.251 1.638 92 12 19 45.8 +18 05 1. 277 1.812 104 22 19 22.6 +18 03 1.313 1 .979 116 Jun 1 18 57.7 +17 20 1.368 2. 140 127 11 18 33.2 +15 54 1. 449 2.296 137

21 18 10.9 +13 54 1.562 2.448 143 Jul 17 52.1 +11 34 1.706 2.595 143 11 17 37.4 +09 07 1.881 2.738 140 21 17 26.7 +06 43 2.083 2.878 133 31 17 19.6 +04 27 2.308 3.015 126

T 1976, Feb. 25.1990 E.T. w = 358?419r q 0.196626 AU b), = 118?226 1950.0 i = 43?0601 (Elements from Marsden, 1975.)

TABLE II. PARTICIPATING OBSERVERS

Leo Boethin The Philippines John Laborde Unspecified Dennis Bohn Mt. Horeb, Wisconsin Ric Lasher West Palm Beach,FL John E. Bortle Stormville, New York Helen Hines Phoenix, Arizona Charles F. Capen* Flagstaff, Arizona Daniel Louderback South Bend, Washington Regulus Capen Flagstaff, Arizona Rainer Lukas Berlin, Germany

Marco Cavagna Milan, Italy Russell C. ~laag St. Joseph, Missouri Jack Child Fullerton, California Joseph Marcus St. Louis, Missouri Robert Clyde Streetsboro, Ohio Leonard Matuszewski Paramus, New Jersey Peter L. Collins Cambridge, Massachusetts Marvin J. Mayo Chatsworth, California Daniel Costanzo Arlington, Virginia Anita McConnell Ridgecrest, California

Kenneth J. Delano Fall River, Massachusetts Danny McCoy Webster, Florida Michael Fornarucci Garfield, New Jersey Claude McEldery Dearborn, Michigan George Gliba Chagrin Falls, Ohio James McMahon Ridgecrest, California Daniel W. E. Green Boone, North Carolina David D. Meisel Geneseo, New York Martin Grossmann Gronau, West Germany Christopher Millward Vancouver, Canada

Charles Hughes Dearborn, Michigan Dennis Milan Massachusetts Albert Jones Nelson, New Zealand R. B. Minton Tucson, Arizona Bruce A. Krobusek Ravenna, Ohio Charles S. Morris West Lafayette, Indiana Gary W. Kronk Edwardsville, Illinois Wolfgang Muhle Stuttgart, West Germany Conrad Kussner West Palm Beach, Florida Thomas O'Hara Fullerton, California *Unless otherwise noted, observations under this surname are by this person. 75 TABLE II. PARTICIPATING OBSERVERS (Cont'd.)

Stephen O'Meara Cambridge, Massachusetts Robert B. Slobins Fall River, Mass. Chet Patton Buchanan, Michigan Doug Smith Rochester, New York Cliff Perkall West Palm Beach, Florida Jim Soder Sidney, Ohio Alain C. Porter Narragansett, Rhode Island Christopher Stephan Solon, Ohio V. Riyan Massapequa Park, New York George F. Stillwell Rodgecrest. CA

Tim Robertson Sepulveda, California Gregg D. Thompson Brisbane, Australia Tom Ruen Detroit, Michigan Charles Townsend* Oxnard, California John D. Sabia Scranton, Pennsylvania Peggy Townsend Oxnard, California Jeffrey Sandel Cayce, South Carolina Derek Wallentinsen Albuquerque, NM Emilio Sassone-Corsi Naples, Italy David D. Weier Mt. Horeb, Wisconsin

Paolo Sassone-Corsi Naples, Italy John West Bryan, Texas Mike Sills University Heights, Ohio John Wetsch Killdeer, N. Dak. Karl Simmons Jacksonville, Florida *Unless otherwise noted, observations under this surname are by this person.

TABLE III. LUNAR PHASES

Date Phase Date Phase 1975/6 1976 Nov 18 FM Apr 14 FM 26 L 21 L Dec 3 N 29 N 10 FQ May 7 FQ 18 FM 13 FM 25 L 20 L Jan 1 N 29 N 9 FQ Jun 5 FQ 17 FM 12 FM 23 L 19 L 31 N 27 N Feb 8 FQ Jul 4 FQ 15 FM 11 FM 22 L 19 L 29 N 27 N Mar 9 FQ Aug 2 FQ 16 FM 9 FM 22 L 18 L 30 N 25 N Apr 7 FQ Sep 1 FQ

N = New Moon; FQ = First Quarter; FM = Full Moon; L = Last Quarter

TABLE IV. NUCLEAR OBSERVATIONS OF COMET WEST

1976 U.T. Observer Nuclei Notes

1. Feb 13.31 Thompson very faint, yellow 2. Mar 2.22 Muhle starlike 3. 4.46 Sandel 3" nuclear condensation 4 4.53 Minton elongated 4"-5" condensation 5 5.22 Muhle 2 first multiplicity 6. 7.57 Townsend 2 inside 6" diameter 7. 8.41 Bortle 2 component B in PA 340°, 3" 8. 8.41 O'Meara 2 9. 8.53 Capen l+ possible multiple structure 10. 9.38 O'Meara 2 11. 9.52 Minton false nucleus 4"x8" 12. 10.51 Capen 1+ blue nucleus, multiple 13. 11.39 O'Meara 4 FA's 300°, 330°, 350° 14. 11.42 McEldery 2 two bodies within coma, 4" separation 15. 11.44 Sandel blue 6" central condensation

76 TABLE IV. NUCLEAR OBSERVATIONS OF COMET WEST (Cont'd.) 1976 U.T. Observer Nuclei Notes 16. Mar 11 . 52 Minton 1 false nucleus 3"x6" 17. 12.41 Bortle 4 B, 4"-5", 345°, 1.3 mags. fainter than A; C, 2", 295°, +1~0; D, 2", 15°, +2~0. 18. 12.41 Sabia 4 8th mag. in two pairs 19. 12.42 Porter 1 nuclear detail suspected 20. 14.40 Bortle 3 B, 8", 330°, +2m; D, 3", 345°, +2~5 21. 14.53 Lines 4 stellar nuclei 22. 15.52 Capen 4 3 diffuse condensations 23. 16.52 Capen 3 4th suspected 24. 18.35 O'Meara 4 PA's: B, 315°; C, 270°; D, 360° 25. 18.40 Bortle 4 B, 12", 325°; C, 8", 295°; D, 6", 335° 26. 20.40 Bortle 4 27. 22.39 Bortle 3 A, B, D 28. 23.38 O'Meara 3 B, 17", 325°; D, 5", 335° 29. 23.39 Bortle 3 A, B, D 30. 24.33 O'Meara 3 B, 14", 320°; D, 6", 330° 31. 24.40 Bortle 3 A, B, D surrounded by a 6"x20" condensation 32. 24.40 Sabia 3 A, B, D; B, 3", 342°; D, 1~'5, 36° 33. 24.52 Capen 2 bluish-white 34 25.33 O'Meara 3 A, B, D; B, 14", 320°; D, 6", 330° 35 25.39 Bortle 3 A, B, D; B, D rather faint 36. 26.38 Bortle 2 A, D 37. 26.40 Sabia 3 A, B, D; B, 328°; D, 347°; D nebulous 38. 29.33 O'Meara 3 A, B, D; B, 20", 315°; D, 6", 325° 39. 29.38 Matuszewski 1 A 40. 29.39 Sabia 3 A, B, (320°), D (346°) 41. 31.38 Bortle 3 A, B, D 42 Apr 1.16 M'uhle 3 43. 1.38 O'Meara 2 A, D (8", 325°) 44. 7.40 O'Meara 2 A, D (10", 318°) 45. 8.31 O'Meara 2 A, D (10", 318°) 46. 10.37 Sabia 2 A, B; B brighter than A 47. 10.37 Bortle 3 A, B, D; tail ifiPine ori~ina tes from nucleus A 48. 12.37 Bortle 3 A, B, g; B, +1.5& D, +1 m 49. 13.37 Bortle 3 A = 12.8; B = 14.0; D = 13.4 50. 14.38 O'Meara 2 A, D (8", 320°) 51. 15.38 O'Meara 2 A, D (8", 320°) 52. 17.35 Bortle 1 A 53. 23.31 Bortle 3 A 12~8; B 14~1; D 13~9 54. 24.29 Bortle 3 A 12~7; B 14~5; D 12~9 55. 30.29 Bortle 3 A 13~3; B 14~7; D 14~2 56. May 4.29 Bortle 3 A 13~2; B 14~8; D 14t;I4 57. 5.28 Bortle 3 A 13~3; B 14~8; D 14~4 58. 9.23 Mil on 3 59. 10.72 Jones 1 13th m~g. 60. 13.32 Bortle 2 A = 13.0; D = 13~3; stellar object in PA 135° 14" distant from A, not a star, 13.2 mag. 61. 21 .26 Bortle 3 A 14~7?; D = 13~3 62 23.36 Bortle 3 A D 14~8;m = 14~3 m 63. 24.26 Bortle 3 A 14m7; D = 13mg 64. 28.27 Bortle 3 A 14mB; o = 13.~ 65. Jun 5.27 Bortle 3 A 14. 7?; D = 14.5 66. 27. 13 Bortle 1 A 14~6 67. 28.13 Bortle 3 A 14~5; B = 15~0; D 15~0 68. Jul 2.22 Green 1+ very faint nuc~ei 69. 18.10 Bortle 3 A, B, D all 15.0 70. 19.10 Bortle 3 A, B, D all suggested; mag. 14t;Ig

77 comet were 'side wings' and a 'rearward projecting spike.' The leading edge of the parabolic-shaped head envelope was observed to be much brighter than the 'rearward projecting spike' and the trailing edge of the 'wings.' As the contrast ratio of comet light to sky background light changed, so did the apparent structure of the cometary head," (Townsend, 13-cm catadioptric, Ojai, CAl. On March 8.53 Capen noted some "faint whiskers" on the right side of the coma and extending a short way up the tail. Slobins at Mt. Wachusett, MA estimated DC (degree of condensation) at 7 and saw a yellow coma 1/2 degree in diameter (eye) and a jet in the direction of the comet's gas tail in a 8-cm refractor. Muhle, like Slobins, reported a yellowish coma (11.19), but Matuszewski and Porter saw a markedly bluish or bluish­ green coma (March 12th). Sabia observed a small, bright, blue-white cc with well­ defined boundaries elongated in PA 202° on 8.43 in a 23-cm refractor at 150x. On the 11th, McEldery saw a "very great condensation; blue-white color." The coma remained strongly condensed--the degree of condensation most often estimated as 8--through mid-March, only dropping to a moderate condensation of 5-7 by month's end. There was some confusion between the coma and strongly condensed portions of it and the nucleus. Capen described the coma (nucleus) as multiple in 20x80's on March 10, with its southern portion bluish. Diameters ranged from 2-3 arc-minutes (Bortle) through 10' (Bohn-Weier) to 30' (Slobins). A tail spine was reported by several people: Sandel noted a central location in the beginnings of the tail and Bortle found it to be 10' long, straight, and in PA 304°. The parabolic envelope was still prominent, though the nucleus was no longer at its focus. O'Hara noted a jet in PA 270°, possibly identical with this spine (12th, 13th). Maag observed Comet West around March 13.50 U.T. He described a coma "noticeably elliptical in shape," with a very symmetrically shaped comatic envelope, slightly brighter on the north side. "Small jets" 0.05 degrees behind either side of the nucleus and a central spine, definitely more dense than the coma, extended away from the nucleus in the direction of the tail. Estimated length of this spine was 0~25. Sabia also reported two bri_ght jets approximately 3' long emanating from the nucleus ( 12.41). "Large, bright coma. One long and one short spike. Three nuclei (were) seen. (I) suspect a fourth condensation" were Capen's remarks on March 16.52. He observed through a 50-cm refractor at 170x. O'Hara had noted a circular green symmetrical coma with no shells or jets but with a distinct nuclear condensation (14.54). Even by March 20.40 the appearance of Comet West's coma was much the same to Bortle who again found it to be 3' in diameter, DC=7 with a parabolic envelope and tail spine. Delano observed the coma to be round, 2 1/2 minutes in diameter, with a cc 80" by 50, "elongated NE-SW, brighter at the ends, and giving the appearance of being somewhat dumbbell shaped (March 22.40, 20-cm catadioptric, 264x)." Porter ( 22.41) saw an active coma, the central part being elongated in PA's 154° - 334°. The overall diameter was 4", and the coma appeared mottled. Faint extensions of the coma were seen at PA's 108° (approximately opposite the tail) and 59°. The coma was strongly blue, and he called it DC=6. Sabia (March 23.38) again saw two bright jets coming from the cc, 6' long and in the same PA as the tail (270°). The coma had a small elongated condensation with the major axis in PA 142°. The DC was estimated as 9. These were typical late March observations. Throughout the rest of the apparition the coma became generally larger and more diffuse. In April, the circular coma was generally 5' across and moderately condensed. No jets were seen by most observers, though O'Meara saw several on three nights through mid-April; and Matuszewski tentatively identified a pair on the 23rd. He was the only one to report a cc in the coma (early in the month). On May 1.25, O'Meara called the coma's shape "elongated trapezoidal" in the 23-cm Clark. According to his observations, the coma was split into two distinguishable portions connected by a slight haze, each with its own stubby tail (May 14.23). During June and July the comet was very diffuse and was becoming difficult to see. Using a 20-cm Newtonian at 43x, Dan Green called a 7' tail "difficult to distinguish from an elongated coma." The object was very diffuse with very faint nuclei visible (July 2.22). Jones called the comet very slight and saw a faint, diffuse coma in a 32- cm reflector at 86x (June 26.48). By late July (18.18), Morris said the coma was ill­ defined with his 15-cm f/4 reflector at 24x; DC=O. On August 3.17, Bortle estimated DC at 0: "coma circular, extremely diffuse." Observed (d) and actual coma diameters (D) are presented in Table V.* The diameter in kilometers is calculated assuming sph~lic~yy: D = 6d 43,516.26 km arc-min AU , with d in arc-minutes, or D = 6sin d AUkm' where 6 is in AU's. No attempt was made to correlate coma diameter with solar distance. Any effort to relate in detail such a heterogeneous set of diameter estimates, affected by moonlight, twilight, weather, observer, telescope, etc., is dubious at best. In this regard, Sabia's

*Contained in a later installment of Mr. Wallentinsen's paper.

78 graphical result with Comet Kohler (Sabia, 1979) is essentially meaningless; and his curve appears to be principally the result of moonlight (pre-q) and paucity of observa­ tions (post-q). (to be continued) BOOK REVIEWS Earthlike Planets, by B. C. Murray, M. C. Malin, and R. Greely, W. H. Freeman & Co., San Francisco, CA. $24.95 hardback, $14.95 paperback. Reviewed by Winifred Sawtell Cameron This book about the inner terrestrial planets of the Solar System is a non­ mathematical, informative synthesization of the knowledge gained thus far from the space exploration of Mercury, Venus, Earth, and Mars. Included also are some of the moons of Jupiter which have many characteristics similar to the inner Solar System objects. The book starts with a short review of hypotheses of origin and evolution of the Solar System held prior to space exploration, then proceeds to discussions of each of the planets and their characteristics as revealed by the space missions, including the manned expedi­ tions to the Moon. It is the latter that provide much of the ground truth, along with geological and geophysical knowledge of the Earth, for interpretation of the remote­ sensored data obtained of the other objects. Chapters are devoted to the characteristics and results from impact, from the work of gravity, from the work of wind, and from glacial activity. Next, internal activity such as volcanism, tectonism, plate tectonism, and convection are discussed. These discussions are succeeded by ones treating each planet and its variety of features and terrains, starting with the Moon. Finally, a section on comparative planetology treats the possible common features among objects such as craters, plains, and volcanism. The book is beautifully illustrated both with clarifying diagrams and well­ reproduced photographs, a few of which are in color. There were very few errors noted, the most conspicuous being the following; p. 59, the date for the Pioneer Venus Pre­ liminary Science Report is given as 1969 and should be 1979; the caption for the figure on p. 139 reads "squares," but should be "circles"; caption for figure 5.2, p. 197 reads "11km" thick for the lunar mantle, which must be in error, 5perhaps 1100km was intended; and in figure 5.3, p. 199 in the ordinate scale the 10 should read 5. In the treatment of Mars I was disappointed that the feature "White Rock" was not mentioned since it is a quite peculiar and different material than is found elsewhere, although I have seen at least two other photographs showing similar material. I also think more discussion of the biological experiments on the Viking missions should have been included. Only the organic molecule experiment was discussed. There also should have been more emphasis on silicic volcanism and its production of large areas of rock such as ignimbrites which have played such a prominent part in western U. S. and other parts of the world. There may be counterparts on other planets. The photographs are identified in an appendix which also tells how they may be obtained and from where, e.g., the National Space Science Data Center (NSSDC). The identifications are necessary for ordering from the various repositories. The book is highly recommended for non-technical persons who are interested in the nature of the solid planets and satellites of our Solar System. The authors are dis­ tinguished experts in the fields of geology and geophysics and were active in the space missions to the planets. * * * * * Principles of Astronomy, Second Edition, by Stanley P. Wyatt and James B. Kaler. Allyn and Bacon,:Boston, MA 02210. 512 pages. 1981. Softback. Price $20.95. Reviewed by Russell C. Maag This popular textbook for an introduction to astronomy at the college or university level has been used extensively by many classes. This latest edition has been considerably revised as well as added to in terms of the latest space vehicle investigations of the planets and the satellites of the Solar System, the structure of the Milky Way Galaxy, the spatial distribution of galaxies, and considerations involving the latest theories concerning the state of the universe. The preface states that Stanley P. Wyatt died on December 6, 1980. In the class­ room he was a teacher's teacher, in the office a colleague's colleague, and to those who knew him a friend's friend. Many of Dr. Wyatt's former students are the living testi­ mony to a well-founded new generation of astronomers. The chapter headings are as follows: "Prospect, Planet Earth";"Earth, Sky, and Time"; "Atoms, Radiation, and Telescopes"; "Our Moon"; "Planetary Motions"; "The Principal Planets"; "Asteroids"; "Comets and ";"The Solar System: Origin and Evolution"; "The Sun"; "The Stars: Observable Properties"; "Multiple Stars"; "Clusters and Associations"; "The Stars, Intrinsic Properties"; "The Variable Stars"; "Matter Between the Stars"; "The Stars: Evolution"; "The Home Galaxy"; "Galaxies"; "The Universe of Galaxies"; and "Retrospect."

79 The text is clear, logical, and concise with a minimal use of mathematics, making this book a useful and highly recommended reference work on basic astronomy for both the amateur astronomer and the general reader wishing an update in this field. * * * * * Comets - Readings from Scientific American, with introduction by John C. Brandt. W. H. Freeman and Company;-san Francisco, CA 94104. 92 pages, illustrated. 1981. Prices $11.95 hardbound, $5.95 paperback. Reviewed by John D. Sabia I imagine just about every amateur astronomer has been asked about the return of Halley's Comet and has had inquiries about the 1910 passage. Well, if you've been doubtful of the answers, this book can clear up the subject. The 11 1/2 by 8 1/2 inches hardbound book contains many fine reprints from the pages of Scientific American over the past seventy years. Before the reader starts on the finely writ ten articles, he is given a review covering thirteen pages on "The Astronomy of Comets" that is extremely well written and is easy to follow for the average layman. The use of some charts and diagrams may appear confusing, but this is explained well in the text. An introduction covering the papers of cometary astronomy published in Scientific American follows the development of our present views on the physical nature of comets. It concludes with the plans (at the time of writing) for a possible Halley Comet intercept mission for 1985-1986. This plan is also referred to by Whipple later. A full thirty-eight pages contains information on Halley's Comet. The chapters cover a wide range of historical accounts in art and literature down to the most recent scientific investigation conducted during the year 1910. The reader finds, in Chapter Two, reports on the 1910 apparition of Halley's Comet. They are a mixture of reprints dealing with pre-discovery announcements, an orbital ephemeris, and the transit of the Halley's Comet nucleus across the face of the Sun. One can get a perspective on how the comet, Moon, and planets were placed in the sky from the monthly sky calendars of May and June, 1910, written by Henry Norris Russell. A fine biography of Edmund Halley closes the subject. We find in Chapters Three through Seven articles on the model of cometary nuclei and the appearances of tails and their formation. More recent studies on the rotation of cometary nuclei and compositional structure are discussed on a detailed level. The next two chapters examine ideas presented previously concerning the origin of comets in the formation of the Solar System. The discovery of the solar wind relates to the theme of comet tail formation and characteristics. I must say that the final chapter of a few short news items does little for the book because they lack continuity. This chapter could have been replaced with a and/or a descriptive narrative about brighter comets of recent years. In my opinion, this book is a great source of reference. It will be of considerable value to instructors of astronomy. There is hardly a trace of printing errors. Not much which is written for the layman concerning comets can match the well-presented information within this worthy book. * * * * * Orbiting the Sun, by Fred L. Whipple, Harvard University Press, Cambridge, Massachusetts,-,g8-1-.- 338 pages. Price $20.00. Reviewed by Jose Olivarez, Omnisphere Earth-Space Center Orbiting the Sun by Fred L. Whipple is one of the Harvard Books on astronomy. It is an expanded-and-up-to-date edition of Earth, Moon, and Planets, a long-standing intro­ duction to the Solar System which originally appeared ~1941. That book has gone through three previous editions; and the current text retains the original format and much of the original contents, especially in the first 8 chapters. However, the rest of the present book presents much new material and reflects the major discoveries of the space probes to the planets up to and including Voyager One's flyby of Saturn in 1980. Like its predecessors, Orbiting the Sun is a highly readable and charming book. Dr. Whipple's friendly and knowledgeable "presence" is noticeable in every chapter. Also, his declared object of providing the reader with a basic foundation of Solar System astro­ nomy through the simple presentation of scientific principles is very well achieved. The first four chapters introduce the reader to general Solar System physics in layman terms and include one of ~he best accounts on the discoveries of and Pluto which this reviewer has eve!" read. Indeed, Chapter 3, "The Discoveries of Neptune and Pluto", is a masterpiece of substance and brevity-the story is told in only 9 pages. Chapters 5 through 15 are devoted to series to the Earth, Moon, and planets where the newly accumulated knowledge of these bodies is skillfully presented. In these pages we

80 learn that "among the active forces that are probably most important today in altering the Moon's surface are human beings" and that "we know Mars better today than we knew the Moon before the space program." There is nothing to criticize in Dr. Whipple's fine text. The only weak points in the book are the many black and white photographs, some of which are not well reproduced. (There are, however, four color plates.) Also, one minor error occurs on the lunar features chart on page 117 where the crater Euclides is misidentified as Aristarchus There are many good reasons why this book's predecessor (Earth, Moon, and Planets) has gone through three editions since 1941. Some of these are~fine chapters on "How the System Holds Together", "The Nature of the Moon", and "Mars". However, two of the chief reasons must have been the book's charm and the author's frequently astute observations on the Moon and planets. These two qualities are retained in Orbiting the Sun and practically guarantee that, like its predecessor, it too will go through several more editions. * * * * * Sphere, Spheroid and Projections for Surveyors, by J. E. Jackson, 1980, Halsted Press, John Wiley and Sons, Inc., New York. ISBN 0470-27044-6. Price $37.95. 138 pages plus index and two problem sets. Reviewed by D. D. Meisel Those of us who have recently had to hire surveyors to establish property lines now know one of the reasons why the fees are so high. If I were a student forced by my professor to buy a book at nearly $0.30 per page, I would be outraged unless it contained real money-making tips that could last a lifetime. For the average amateur astronomer to shell out nearly $40.00 for this book, however, is masochistic! If you want a self-taught lesson in navigation or spherical astronomy, this book is not appropriate. Nevertheless, for a professional surveyor, cartographer, or geographer, this book could be of great value. In particular, if you are writing computer programs for surveying, geodetic data analysis, or commercial map making, this book, or one like it, would appear likely to be a constant reference. Although its rather handy size makes it ideal for field use, no provision for weatherproofing was made. In this reviewer's view, Part I of this book starts being a somewhat unique spherical trigonometry reference only after page 35 where Legendre's Theorem is dis­ cussed. This part is followed by a short discussion of surveying errors. Part II of the book deals with spheroidal (ellipsoidal) geometry as it applies to geodesy. This section follows the development of the first section and includes a discussion of errors. The bulk of this material is not included in most spherical astronomy texts. Part III--Map Projections--contains a summary of spherical and spheroid map projections in common use. For the professional geographer, geologist, or map maker who wants a quick refresher course, this book would be highly recommended in spite of its price. For the most part, typographical errors are few, except for the first line of section 1.1 where the words "the" and "of'' are omitted. The reviewer has not checked all of the formulae, but a spot sample reveals careful proofing in the parts examined. My main complaint is the lack of text references for the various methodologies. Three general references--one for each part--are given at the text's end, but these simply can't be all! Perhaps the author thinks that his students don't care about the origin of the techniques, and perhaps that is true also of most instructors of this subject; but the reviewer thinks not. One should be able to check derivations-­ particularly for series expansions with numerical coefficients. * * * * * Daytime Star, by Simon Mitton. Charles Scribner's Sons, 597 5th Avenue, New York, N.Y.~ ~1. Hardbound. Price $14.95. Reviewed by Freeman D. Miller, University of Michigan Simon Mitton's literary credits include two well-received books, Exploring the Galaxy and The Crab Nebula. Now Daytime Star fills a gap in the list of recent books for non-professionals-sy-surveying solar topics from Stonehenge to the neutrino problem. The first three chapters deal with the earliest evidences of interest in the Sun, with the Sun as the nearest star, and with observational techniques for amateurs and professionals. Chapter 4 takes the reader on a quick jaunt from the center of the Sun into the solar wind, after which the two following chapters return him to the solar interior for a good exposition of energy generation and the related neutrino problem. Chapter 7 is devoted primarily to solar origin and evolution, with some attention to more massive stars, and of course to supernovae. The next two chapters describe observable solar phenomena - sunspots, prominences, flares, and magnetic fields - leading on to the corona, the solar wind, and solar-terrestrial phenomena in Chapters 10 and 11. The final chapter presents the author's views on coping with the coming energy crunch; the reviewer was interested to note how little new can be added to the corresponding chapter in the 1959 edition of the late Donald Menzel's Our Sun.

81 In his two earlier books, Mitton maintained a pleasant level of informality; but in Daytime Star his vocabulary is too flamboyant for this reviewer's taste. Thus, the end of solar evolution is "uncivilized"; faculae are a "type of wrinkle in the Sun's battered skin"; flares "rampage through the regions where very large spots are fester­ ing"; and Wolf numbers are a "measure of solar acne". Editorial lapses inevitable in a first edition appear. On page 17, energy released in the core reaches the photosphere in a million years, but on page 73 this becomes ten million. The diagrammatic cross section of the Sun on page 58 does not agree with the description on the following page. On page 109 the synodic period of solar rotation at the poles is given as fourteen days, perhaps a transposition of the digits in "forty­ one" written originally in numerical form. Linear units are usually metric, but the unit of mass is the ton (occasionally that sturdy British unit, the tonne). A few more substantive criticisms may be put on record. Rubbish thrown out of a spacecraft (p. 25) escaping from the vicinity of the Sun would not "crash down to the solar incinerator". The statement on page 28 that in the presence of a strong flux of solar UV radiation "we would have evolved with very thick skins" is highly conjectural. To say that "the Sun's performance is measured on a daily basis at many thousands of weather stations" (p. 38) gives an exaggerated idea of the volume of truly solar observa­ tions. Illustrations are numerous, and with a few exceptions, well reproduced. Some members of A.L.P.O. might find this book an entertaining introduction to matters solar, but the reviewer feels that the majority would prefer a more sophisticated account. * * * * * Webb Society Deep-Sky Observer's Handbook- Volume 4: Galaxies, Edited by Kenneth Glyn Jones. Enslow Publishers, Hillside, New Jersey• 07205. 238 pages, 1981. Price: $15.95, softbound. Reviewed by Julius L. Benton, Jr. Preceding volumes of the Webb Society Deep-Sky Observer's Handbook have dealt with double stars (Volume I), planetary and gaseous nebulae (Volume II), and open and globular clusters (Volume III). Each volume has been relatively complete and quite comprehensive within itself on each topic; and the newest edition (Volume IV), Galaxies, is no excep­ tion. In fact, this latest edition brings forth a good synthesis of much of the under­ lying material of the previous treatises. After an introduction and a historical perspective, a meaningful exposition unfolds in Part One whereby the reader is acquainted with various properties of galaxies: classification, distribution, formation and evolution, gaseous and stellar content, galactic nuclei, etc. Additional information is presented on Seyfert, Quasi-stellar, and related objects, as well as interacting and peculiar galaxies. The final sections of Part One deal with catalogues and observations of galaxies. If the user is to get the most out of deep-sky observations, the material in Part One should be carefully read and studied before using the book as a reference or going to the telescope. Part Two is a catalogue of galaxies, containing observations and descriptions of some 275 objects by 19 observers using instruments of from 2 1/4 to 152 inches in aperture. Following the catalogue, in which the designations and positions of galaxies are given, some 156 field drawings and sketches are presented. On some objects, more than one drawing is given, showing how increasing aperture affects visibility of these galaxies. One minor criticism is that some of the galaxies drawn in this section of Part Two do not appear in the catalogue. In Part Three one finds a catalogue listing of selected interacting and peculiar galaxies, Zwicky compact galaxies, Seyfert galaxies, and some variable sources. Finder charts are provided for a few of these objects to assist the reader in finding them at the telescope. The reader, however, is encouraged to consult other sources for more detailed data on the galaxies presented in Part Three. A good star atlas should, as the author recommends, accompany the use of the Handbook. The book ends with ample Appendices covering information on emission regions in a few galaxies, galactic distances and non-velocity redshifts, faint systems near NGC galaxies, etc. A meaningful Bibliography gives suggested sources for further reading and technical data. The planetary observer, who wants some digression away from routine studies of planetary surfaces and atmospheres, will find this book a very useful tool in locating numerous faint galaxies within reach of his telescope. Fortunate, indeed, is the individual who has an observing site away from pollution and city lights; and he should not pass up an opportunity to view these remote objects. Further, the complete set of Handbooks should be on the shelf of the amateur astronomer who wants a handy encyclopedia of faint deep-sky objects infrequently mentioned in most astronomical texts.

82 NEW BOOKS RECEIVED By: J. Russell Smith and Charles S. Morris The Milky Way, Fifth Edition, by Bart J. Bok and Priscilla F. Bok. Harvard University Pres~Cambridge, Mass. 02138. 1981. 356 pages. Illustrated and hardbound. Price $20.00. Notes by J. Russell Smith. If you are interested in the Milky Way, you will want to read this book. Recent research has brought about a different picture of our Milky Way. The chapters are as follows: Presenting the Milky Way, The Data of Observation, The Sun's Nearest Neighbor, Stellar Populations, Moving Clusters and Open Cluster~ Pulsating Stars and Globular Clusters, The Whirling Galaxy, The Nucleus of Our Galaxy, The Interstellar Gas, Dark Nebulae and Cosmic Grains, The Spiral Structure of the Galaxy, and Our Changing Galaxy. You will find the book easy reading as well as a modern reference. * * * * * The Physics of the Interstellar Medium, by J. E. Dyson and D. A. Williams. Halsted Press~ division-of~hn Wiley & Sons, Inc., New York. 10016. Price $24.95. Notes by Charles S. Morris. This book is designed as a textbook for university students. It is perhaps best described not as an astronomy book, but rather as a physics text in an astronomy setting. The book deals with a number of specific problems relating to the interstellar medium. For instance, the expansion of nebulae is covered in one section. This textbook relies heavily on equations in its discussion of the various situations it covers and provides problems at the end of each chapter (with some answers in the back of the book). This is definitely not a book for an arm-chair astronomer. However, those people with 2 background in physics might find it of interest.

THE A.L.P.O. AT ASTROCON '81 By: Don Parker and Jeff Beish, A.L.P.O. Assistant Mars Recorders This year's Astronomical League Convention,AstroCon '81, was held in Kutztown, Pennsylvania on Tuesday, August 11-Sunday, August 16. Despite travel problems caused by the air traffic controllers' strike, nearly 500 Astronomical League members attended, representing all of the League's regions. One astronomer even came from New Zealand! The A.L.P.O., which was invited to participate in AstroCon '81, fielded approximately 30 mem­ bers. For the authors, this presented an excellent opportunity to renew old friendships as well as to meet observers whose work they have admired for many years. The first two days of the convention were given to well-organized tours of nearby observatories, optical instrument companies, and planetaria in New York City and Philadelphia. There was also an excellent tour of the Smithsonian Aerospace Center in Washington, D.C., as well as trips to the historic Pennsylvania Dutch Country and to Atlantic City (quite a contrast! ) . On Thursday, August 13, after opening remarks by the Astrocon '81 Chairman, the Hon. Kenneth H. Mohr, Dr. Harry L. Shipman opened the proceedings with an excellent lecture on black holes. Dr. Shipman, whose lucid explanations of relativistic physics have appeared in books and popular articles, set the stage for things to come. The authors do not recall having attended any other meeting, either on astronomy or in their own professions,where all the invited lecturers were so articulate and informative. The remaining speakers, Dr. George 0. Abell, Dr. William Brunk, Dr. George F. Reed, Dr. Frank D. Drake, and Dr. Owen Gingerich, well known astronomers and top men in their fields, covered diverse topics ranging from history and astrology to modern cosmology. The AstroCon '81 committee is to be commended for obtaining such outstanding speakers. Enough A.L.P.O. papers were submitted so that two sessions were required, the first being convened on Thursday afternoon by moderator John vJestfall. Mars Recorder Cl'Erles Capen opened the session with an interesting discussion on Earth-based observations suggesting the possibility of volcanic activity on Mars. A.L.P.O. Associate Director Westfall continued in the same vein by proposing that volcanic erruptions on Io's limb might be visibre from Earth as an elongation of the satellite or its shadow. A.L.P.O. Saturn and Venus Recorder Julius Benton presented a simultaneous observation program for Venus' current apparition and discussed methods of observing that planet. Next, Phillip Budine, A.L.P.O. Jupiter Recorder, gave a history of Jupiter's South Tropical Zone Disturbances and discussed the effects of these phenomena on the Great Red Spot and on the South Equatorial Belt Dis­ turbances. Steven O'Meara from~ and Telescope magazine gave an interesting paper in which he showed pre-Voyager Earth-based observations which revealed the curious spokes on Saturn's rings. Unfortunately, these observations lacked confirmation and therefore went unheeded. It is notable that all of these papers point out the fact that very useful work can be, and has been, done by ground-based astronomers with relatively modest equipment. What is needed is confirmation by others observing simultaneously and using

83 Figure 21. The Kutztown State College Planetarium and Ob­ servatory. Figures 21-24 are photographs of AstroCon '81 taken and contributed by Dr. Donald Parker.

Figure 22. The A.L.P.O. Exhibit at AstroCon '81. From left to right: Chick Capen, Jeff Beish, and Phil Budine.

Figure 23. ~-unc:Jr Recorder, Winifred C?r.meron discusses the Ll:nc:r Tr2nsier:t Figure 24. Jupj_ter Recorder Phill~p Pheno~ena A.~.P.O. Program. Budine discusses South Tropica_l Zone Dis turbc,r:ces. quantitative methods whenever possible. The planetary-astronomy' sessions continued with Alain Porter's description of the work of the A.L.P.O. Minor Planets Section, including astrometry, photometry, occulta­ tion work, and search and recovery programs. He cited some spectacular successes by A.L.P.O. members in determining rotation periods of various asteroids. J. Gunther, publisher of Tonight's Asteroids, presented an historical review of asteroids named after amateur astronomers. One of the highlights of the A.L.P.O. session was the announcement that a newly discovered asteroid ("Jugta") has been named after Dr. Gunther. Next, Steve O'Meara returned to discuss techniques for observing comets' nuclei. Chick Capen closed the first session with a presentation of Jeff Beish's computer program, with which the Mars Recorders are studying long-term Martian atmospheric phenomena. (In order to make this ponderous task easier, the Mars Recorders request that all drawings be made on the standard report forms or at least on 42-mm diameter disks and that as many observations as possible be made in blue light.) On the next morning, Friday, August 14, A.L.P.O. papers continued with Don Parker's description of his planetary projection camera. He also discussed astronomical seeing in relation to planetary photography. Winifred Cameron then presented the results of her Transient Lunar Phenomena (TLP) program. It appears that TLP's are real and may occur fairly frequently, but more observers are desperately needed for verification of these interesting events. On Saturday afternoon, A.L.P.O. members participated in a workshop on lunar and planetary observing. Westfall, Cameron, Parker, Benton, Budine, Capen, O'Meara, and Porter all presented various aspects of the A.L.P.O. programs. The session was well attended by convention members and generated considerable interest in Solar System studies. It is unfortunate that paper sessions and workshops had to run simultaneously since there were many fine presentations which the authors were unable to attend. After re­ viewing the titles and discussing these sessions with those who participated, we were struck by the sophistication in instrumentation and data analysis available to today's amateur. Many papers dealt with micro-computers and photo-electric photometers. There were also some interesting papers on astrophotography. Walter Hamler (who won first place in three of four categories in the astrophotography contest!) and Mike Reynolds, from Florida, each gave very interesting discussions on techniques for hypersensitizing 2415 Technical Pan film. While most of these papers were presented for variable star, occulta­ tion, and deep sky observers, there was a message for planetary observers: the amateur astronomer of the 1980's will be able to quantitate his observations with more and more preclslon. It is this quantitation, whether on improved photographic emulsions or on computer tapes, that will enable the amateur to make serious contributions to the astronomy of the '80's. As A.L.P.O. members well know, many farsighted professional astronomers are taking advantage of this idea. For example, on Saturday night at the awards ceremony,David W. Dunham received the Astronomical League Award for 1981 for his organization and guidance of hundreds of amateur occultation observers. AstroCon '81 was a very smoothly run convention. Special thanks are due Convention Chairman Ken~eth H. Mohr, Astronomical League President Dr. Orville H. Brettman, Kutztown State College Vice-President Dr. Robert J. Wittman, Mr. and Mrs. Neil Lerner, Peter Detterline, and other members of the AstroCon '81 Committee who worked so hard to make the meeting such a rewarding experience. John Westfall is also to be commended for his organization of the A.L.P.O. workshop. So is Julius Benton for collecting and arranging an informative A.L.P.O. Exhibit. This program was of considerable benefit to both novices and advanced observers, and we hope that a workshop will be a regular part of future meetings. The A.L.P.O. has accepted an invitation from the Astronomical League to participate in its convention, "ALCON - '82" in Peoria, Illinois, on July 22, 23, and 24, 1982. This meeting will be held at the new Continental Regency Hotel and promises to be a fine meeting. A number of well known guest speakers, including J. Allen Hynek and Clyde W. Tombaugh, have agreed to participate. We hope to see many A.L.P.O. members at this meeting.

ANNOUNCEMENTS New Staff Member. On the basis of discussions among Jupiter observers present at AstroCon '81 Mr. Randy Tatum has been appointed an Assistant Jupiter Recorder. He has been a very active observer from 1971 to the present and was an independent co-discoverer of one of the 1975 SouthEquatorial Belt Disturbances on Jupiter. His address is: 3707 ~oody Ave., Richmond,VA 23225. His special interests include the history of Jupiter observations and certain theoretical interpretations of Jovian surface phenomena. ,Information on Comet Halley. Mr. J. Russell Smith has received from the Jet Pro­ pulsion Laboratory-20 copies of a 44-page booklet called The Comet Halley Handbook, An Observer's Guide. This information should be very interesting with the return of this-most famous of all comets scheduled for the winter of 1985-6. Mr. Smith will be glad to mail

85 Figure 25. Julius Benton speaking to Lunar and Planetary Workshop at AstroCon '81. Note text on page 85. Figures 25- 28 are photographs taken at AstroCon '81 by Dr. Donald Parker and contributed by him.

Figure 26. Informal view of the audience of amateur astronomers.

Figure 28. Mr. Alain Porter, now a Figure 27. A.L.P.O. Associate Director graduate student in astronomy at the John Westfall welcomes the attendees on California Institute of Technology, behalf of the A.L.P.O. at the opening speaks on the A.L.P.O. Minor Planets session. Section and its observational programs. 86 copies of the booklet to persons re­ questing them while the supply lasts. Hand Figured Those making such requests should send two dollars ($2.0~) by check or money Telescope Mirrors order to J. Russell Smith, 8930 Raven Drive, Waco, TX 76710, to cover mailing Null Tested and handling costs. Aluminized and Overcoated Voyager 2 Saturn Photographs. The Astronomical Society of the Pacific is Sizes: 4~" to 16" offering prints and slides of the exciting 10" F-6 Mirror $200.00 Voyager 2 spacecraft photographs of Saturn, 12%" F-6 Mirror its rings, and its moons. Selected $325.00 pictures are available in high-quality Also Available: 8 by 10-inch prints and 35-mm slides. Mirror Kits • Refiguring Clear explanatory notes and a table of results accompany each set. For full Telescope Parts & Acce880rias description and a price list, as well Custom Made Telescopes as information about the Voyager 1 photos of Saturn and Jupiter, please send a FREE stamped, self-addressed envelope to: Complete Product Price Ust Saturn Encounter Photos, A.S.P., 1290- On Request 24th Avenue, San Francisco, CA 94122. Honor Won by Dr. Donald Parker. Our ENTERPRISE DPTICB Assistant Mars Recorderwasawarded first P.O. Box413 place at As troCon '81 in black-and-whit.e Placentia, CA 12870 Solar System photography as part of the [714] 524-7520 Astrophotography Contest. A number of his fine results have appeared in this journal. Corrections to Past Issues. In Vol. 28, Nos. 9-10, pg. 197, the third line from the bottom reads in part "Vo~o. 3, October 1980" but should instead read "Vol. 2, No. 4, October, 1980." In Vol. 28, Nos. 9-10, pg. 199, the last sentence in the first paragraph below Table II should be amended to read: "It should be stressed here that magnitude estimates made with the use of a star atlas (where magnitudes are estimated from a graduated scale of dots representing levels-or-stellar magnitudes), as opposed to a catalogue, are usually rather useless; and this is a major cause for discrepancy and scatter among A.L.P.O. observations." Partial File of Journal A.L.P.O. in Europe. Mr. Roger Laureys, Herestraat 5, B-3721 Vliermaalroot, Belgium has a complete file of Journal A.L.P.O., long known by its original title of The Strolling Astronomer, from Volume 10 on to the present. He was able to fill in many missing issues with ones made available by Mrs. Martha Ashbrook from the library of the late Dr. Joe Ashbrook. European colleagues interested in old articles in our journal may find it convenient to contact Mr. Laureys. The only complete files of all our issues known to the Editor are those in the Library of Congress and in the Library of New Mexico State University and his own. Sustaining Members and Sponsors. The persons listed below support the work of the A.L.P.O. by voluntarily paying higher dues, $40 per volume for Sponsors and $20 per volume for Sustaining Members. The generous assistance of all these colleagues is here gratefully acknowledged. Any errors in the list are the fault of the Editor, who would appreciate being told about them. Sponsors. Philip and Virginia Glaser, Dr. John E. Westfall, Dr.James Q. Gant, Jr., Ken Thomson, Reverend Kenneth J. Delano, Frederick W. Jaeger, Harry Grimsley,. Darryl J. Davis, Michael McCants, Dr. A. K. Parizek,Raleigh Crausby, Robert M. Adams, Oscar Monnig, and Dr. David D. Meisel. Sustaining Members.. Sky Publishing Corporation, Charles L.Ricker, Elmer J. Reese, Carl A. Anderson, Gordon n Hall, Joseph ~ Vitous, B. Traucki, H. W. Kelsey, Commander W. R. Pettyjohn, Orville H.Brettman, Brad Dischner, Dr. Julius L. Benton, Jr., H.oy J. Walls, Winifred S. Came~on, Charles S. Morris, Richard J. Wessling, Bill Pierce, Harold D. Seielstad, Dr. Howard W. Williams, Tim Robertson, Dr. Clark R. Chapman, Michael B. Sffiith, R. F. Buller, Stephen Zuzze, Wynn E. Wacker, James H. Fo~ Reverend Robert A. Buss, Harold Stelzer, Jack Ross Dison, Douglas Smith, and Dr. Joel W. Goodman.

OBSERVATIONS AND CO~~ENTS . Those Curious Dusky Spokes in the Rings of Sa turn. We appear to have one more pre- d~scovery Earth-based observation of the strange dusky bands on the bright rings of Saturn dlscovered by Voyagers 1 and 2. See, for example, Sky and Telescope for November 1981 pg. 432. Now Mr. Toshihiko Osawa in Fukuoka, Japan~alls attention to the ' ' dr~wlng reproduced her~ on our front cover. Two dusky shadings border a slightly brlghter patch at the lnner edge of Ring B on the west (left) ansa. His notes at the time of observation follow: "A sharp image was visible occasionally. On the ball the South Equatorial Belt was intense to the right. A rift appeared to exist on the CM

87 (central meridian). A faint band was visible a little south of the SEB. The South Polar Region was unexpectedly dark. The Sotth Temperate Belt was crearly seen. Almost no details were visible between the SEB, south component and the STB. The northern half of the Equatorial Zone was dusky with a faint Equatorial Band. Limb darkenings were equal on the left and right limbs. "The Crape Ring was hard to see off the ball. The inner side of Ring C appeared to be slightly brighter. The Crape Ring was clearly seen on the ball, but not too trans­ parent. Shadings presented a strange appearance on Ring B. The outermost division was well defined on Ring B~' Presumably this "division" is at the place on the drawing where Ring B becomes brighter, about 2/3 of the way from the inner edge to the outer edge. One may suspect that other unconfirmed and unreported observations of odd features in the rings exist in the files of amateur observers; and one may wonder whether a systematic future study by a persistent Earth-based observer might not be informative, granting adequate aperture and good seeing. Concerning Divisions in the Rings of Saturn. Mr. P. J. K. Louwman of Wassenaar, Holland wrote the Editor fi1 part as follows on July 14 and October 12, 1981 : "My main specialty is observations of Saturn and especially its rings. The great number of sub­ divisions in the rings (discovered during the fly-by of the Voyager 1) has, frankly speaking, not come as a surprise to me, for I have predicted them many times, for instance also in a lecture I gave sometime shortly after the Pioneer 11 observations (which did not reveal them yet). These predictions were not based on theoretical considerations, but merely on experiences of famous observers on a few exceptional moments of extraordinarily fine seeing conditions .... r------=------1 "However, I must add that I never suspected (nor even Observing the Moon, dreamt of!) that the number of divisions would run into Planets, and Comets the hundreds, or even, as the Voyager 2 has now revealed, ed. by Chap~an & Cruikshank several thousands. Like you, I expected perhaps a dozen, or so, divisions in the B-ring and half as many in the A­ After decades, the original ring. unproofed draft of this "I have enclosed with this letter a few photo-copies of renowned manual detailing interesting articles concerning this matter .... In the what to observe and record article in Sky and Telescope for July, 1960 you will see on is available in limited pages 22 an~3~e difference between the results of two quantities. experienced observers: B. Lyot and G. Kuiper. Please also note the contents of 'Astronomy: How Amateurs Got There *700 plus pages, numerous First' in The New Scientist, 16 April, 1981. illus. 2 volumes, soft­ "I must statethat I was very impressed by the article cover by W. Livingston in Sky and Telescope for April, 1975. I *$20.00 ppd. a~ convinced that his-8xtremely rare observation [of numerous internal divisions in the rings as seen with the SCHRAMM & GROVES Mount Wilson 100-inch reflector in perfect seeing-no 24151 Las Naranjas detectable image motion] should be regarded as highly Laguna Niguel, CA 92675 reliable, and it was therefore especially this report that influenced my opinion mentioned (predicted) by me during my lecture." __:s:o:m:e~M:o:r:e~I~m~p~r~e~s~s=i~o~n=s~o~f~A~s~t~r~o:c:o:n~':8:1~.-~T~h~e~f~o~l~l~owing comments by Lunar Recorder r Winifred Cameron in a letter dated BOOKS ON ASTRONOMY August 24 1 1981 should encourage $26.85 those whose hard work makes such 39.95

88 LIBRARIAN Mrs. Walter H. Haas The Strolling Astronomer 2225 Thomas Drive Las Cruces, New Mexico 86001 SUBSCRIPTION RATES MERCURY SECTION Richard M. Baum (Recorder) Single Issue (in stock) $ 2.00 25 Whitchurch Road Chester CH3 50A, England 1 Volume (6 issues), U.S.A., VENUS SECTION Julius L. Benton, Jr. (Recorder) Canada and Mexico . $10.00 Darien 13A Village 2 at New Hope 1 Volume (6 issues), other New Hope, Pennsylvania 18938 MARS SECTION countries . $11.00 Charles F. Capen (Recorder, meteorology) 223 W. Silver Spruce 2 Volumes (12 issues), U.S.A., Flagstaff, Arizona 86001 Canada and Mexico $18.00 Donald C. Parker (Assistant Recorder, photography) 12911 Lerida St. Coral Gables, Florida 33156 2 Volumes (12 issues), other Jeff D. Beish (Assistant Recorder, statistics) countries $20.00 9460 Toni Drive Miami, Florida 33157 JUPITER SECTION SPECIAL MEMBERSHIPS Phillip W. Budine (Co-Recorder) Box 68A, R. D. 3 Walton, New York 13856 Sustaining Members . $20.00 per volume, Paul K. Mackal (Co-Recorder) or 6 issues 7014 W. Mequon Road 112 North Mequon, Wisconsin 53092 Sponsors $40.00 per volume, Jean Dragesco (Assistant Recorder, photography) or 6 issues Baile Postal 7108 Cotonou, Republique Populaire du Benin West Africa Rodger W. Gordon (Assistant Recorder) 637 Jacobsburg Road Nazareth, Pennsylvania 18064 ADVERTISING RATES (per issue) Clay Sherrod (Assistant Recorder) P.O. Box 4145 Full Page Display Ad ...... $40.00 North Little Rock, Arkansas 72116 Randy Tatum (Assistant Recorder, History and Theory) Half Page Display Ad 22.50 3707 Moody Ave. Richmond, Virginia 23225 Quarter Page Display Ad ...... 15.00 John E. Westfall (Assistant Recorder, Eclipse Timings) Dept. of Geography Classsified or Listing (per col. in.) 4.00 San Francisco State University 1600 Holloway Ave. Discount of 10% on 3-time insertion. San Francisco, California 94132 SATURN SECTION Julius L. Benton, Jr. (Recorder) Darien 13A NOTICE * Village 2 at New Hope * * New Hope, Pennsylvania 18938 In order to facilitate the reproduction of draw­ REMOTE PLANETS SECTION ings in future issues readers are requested to Richard G. Hodgson (Recorder) exaggerate contrasts on drawings submitted. Dordt College Extremely faint marks cannot be reproduced. Sioux Center, Iowa 51250 Outlines of planetary discs should be made LUNAR SECTION dark and distinct. It is not feasible to reproduce John E. Westfall (Recorder) Dept. of Geography drawings made in colors. Following these San Francisco State University precepts will permit better reproductions. 1600 Holloway Ave. Persons requiring prompt acknowledgement of San Francisco, California 94132 correspondence or contributed observations Winifred S. Cameron from staff members are requested to furnish (Recorder, Lunar Transcient Phenomena) NASA, Goddard Space Flight Center stamped, self-addressed envelopes. Code 601 Greenbelt, Maryland 20771 COMETS SECTION STAFF Dennis Milan (Recorder) 8 Grant St. Maynard, Massachusetts 01754 Dl RECTOR-EDITOR Derek Wallentinsen (Assistant Recorder) Walter H. Haas 3131 Qunicy, N.E. Box 3AZ Albuquerque, New Mexico 87110 University Park, New Mexico 68003 MINOR PLANETS SECTION ASSOCIATE DIRECTOR Richard G. Hodgson (Recorder) John E. Westfall Dordt College Dept. of Geography Sioux Center, Iowa 51250 San Francisco State University Frederick Pilcher (Assistant Recorder) 1600 Holloway Ave. Illinois College San Francisco, California 94132 Jacksonville, Illinois 62650 SECRETARY AND BOOK REVIEW EDITOR LUNAR AND PLANETARY TRAINING PROGRAM J. Russell Smith Jose Olivarez 8930 Raven Drive Dept. of Community Facilities Waco, Texas 76710 225 W. Douglas Wichita, Kansas 67202 STAR ATLASES are our FORTE!

Sky Publishing's array of star maps and atlases has world renown - second only to Sky and Telescope itself - for we can produce and import the many fine publications required by most amateur astronomers and many professionals. Most important, we maintain stocks of these unique publications through the years. There are introductory maps for the beginner, including the magazine's monthly centerpiece, several atlases for intermediate amateurs, and elaborate Czechoslovakian and German productions for the advanced observer and experienced astrophotographer. (Note: Atlas Australis, not listed below, covers the southern sky in exactly the same manner as Atlas Borealis, and is ordered as 6107, $27.50; add $2.00 outside U. 5.)

POPULAR STAR ATLAS ATLAS BOREALIS Suitable for beginners but handy for everyone is this Amateurs working seriously in astronomy and sky book of constellation charts. Against a dark blue photography find this and Atlas Eclipticalis invaluable background .. stars are shown to magnitude 5Yz, with for locating asteroids, comets, deep-sky wonders, and constellation boundaries, Greek letters, and Flamsteed faint stars. The 92,000 stars are coded in six colors to numbers. There are observing lists of conspicuous give their spectral classes. The scale is uniformly two double stars, Messier objects, a constellation index, and centimeters to one degree of sky, Atlas Borealis having star names. Covers the entire sky, for use anywhere in 12 maps for declinations +30° to +50° in steps of 2h in the world. Order 8998 POPULAR ... $5.50 right ascension, eight maps between +50° and +70° in 3h steps, and four charts for the polar region. Wire­ NORTON'S STAR ATLAS and Reference Handbook bound in beautiful red Lexitone, overall size 13 'I• by 19 This is the new, greatly expanded 17th edition of one inches, weight 3 pounds. Add $2.00 postage outside U.S. of astronomy's classic references, which should be on the Order 6018 ATLAS BOREALIS .. , $27.50 desk of everyone interested in astronomy. Its 16 double­ page charts are specially clothbound to open perfectly ATLAS ECLIPTICALIS flat, even though preceded by a 116-page large-format It takes 32 large charts, each rectangular, to cover the reference handbook that gives information on every equatorial zone of the sky between -30° and +30° phase of astronomy of interest to the amateur. With declination, in 1 1/zh steps of right ascension. Some each Norton's we include our handy chart and index of 124,000 stars are plotted, each color coded for quick Messier objects. Order 9005 NORTON'S ... $17.00 comparison with photographs, whether in black-and­ white on different emulsions or in full color. Recognition Skalnate Pleso Deluxe ATLAS OF THE HEAVENS of a star field is almost instantaneous when a print from Each of the 16 charts in this famous aid to celestial an amateur's color transparency or negative is compared observing measures 15 by 21 inches, giving a scale that is with Atlas Ec/ipticalis or Borealis. Wirebound in red adequate for identifying in any part of the sky stars, Lexitone, size 14'1, by 20 inches, weight 4 pounds. Out­ clusters, nebulae, planetaries, galaxies, and strong radio side U. S. add $2.00. sources, the different types of object being color coded Order 6093 ATLAS ECLIPTICALIS ... $29.50 for quick recognition. The Milky Way is shown in great detail, again with color coding for its more intense parts, PHOTOGRAPHIC STAR ATLAS as well as for areas of bright and dark nebulosity. The This comprehensive atlas was compiled by Hans celestial coordinate scales are for the precessional Vehrenberg with twin Zeiss f/3.5 astrocameras at observ­ 1950, matching most modem star catalogues, including ing stations in Germany and South Africa, to include the our own Skalnate Pleso Atlas Catalogue. Wirebound in entire sky. In the northern section, 303 maps cover from dark-blue Lexitone. +90° to -26° in declination, while 161 maps in the Order 6050 DELUXE ATLAS (U.S.A.) ... $17.95 southern section cover -14° to the south celestial pole, All other countries .. , $19,95 giving a good overlap between the sections. Each map is printed on heavy paper, 11 '/, by 8 1/, inches, the field of FIELD EDITION Atlas of the Heavens the chart being 10 degrees square, to a scale of 15 The basic sky maps of the Deluxe Edition are here millimeters per degree of sky. Adjacent maps overlap by reproduced at two-thirds scale, but with white stars on a two degrees, and the average limiting magnitude for stars black background for nonglare use at the telescope and is about 13. Edition A is photo-offset with black stars in the field. Sixteen 18-by-121/,-inch charts with intro­ on a white background; edition B is photo-printed with duction, shipped flat. white stars on black sky. The 24-page explanatory Order 6069 FIELD EDITION ... $6.50* booklet is written in English, French, and German. The DESK EDITION Atlas of the Heavens northern section is boxed in two large containers, the southern section in one. Like the Field Edition, but with black stars and coordinates on white paper, for desk use and easy • *Order 9019 VEHRENBERG NORTHERN A. , , $48.00 marking. On heavy 150-pound paper; 16 charts with (Weight 10 pounds) 9035 B ... $68.00 introduction, shipped flat. • *Order 9027 VEHRENBERG SOUTHERN A ... $30.00 Order 6077 DESK EDITION ... $6.50* (Weight 6 pounds) 9043 B ... $40.00 *SPECIAL COMBINATION: • *Hans Vehrenberg's many other publications are de­ Two sets of either the Field Edition or the scribed in Scanning the Skies. On Vehrenberg orders, Desk Edition, or one of each. $11.50 eight weeks must be allowed for receipt of shipments from West Germany; Customs may collect a small duty. All items described above and in our catalogue, SCANNING THE SKIES, are shipped postpaid both within the United States and elsewhere in the world. Orders should be accompanied with check or money order in U. S. funds.

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