AMATEUR OBSERVATION NETWORK I. INTRODUCTION Amateur observations of periodic Comet Giacobini-Zinner commenced with the visual recovery of the comet by C.S. Morris and S.J. Edberg on 1985 April 13 and ended with A.F. Jones' observation on 1985 December 10. Within that period 1016 magnitude and related visual estimates were made. Fifty-three drawings are are listed spanning June-October and 20 photographs spanning July-September. Observations by 106 amateur astronomers were used in the archive. The observations, compiled by the Discipline Specialist Team (Table I), can be grouped into three distinct categories: (1) Visual-appearance descriptions. (2) Drawings. (3) Photographs. Because of the subjective nature of the visual-appearance observations there is diversity in the type and quality of information recorded in the ar- chive. When a range of values was given by the observer, the more conservative value was entered, i.e. a shorter tail, more diffuse condensation, smaller coma, and fainter magnitude. Drawings present the visual aspect of a comet. To be included in the archive a rendering must reproduce the detail discernible by the observer and must provide information useful to the archive user. All the photographic images listed are on file and were examined for quality before inclusion in the archive. Table I. Discipline Specialist Team of the Amateur Network ________________________________________________________________________________ Team Member Affiliation Responsibility ________________________________________________________________________________ Stephen J. Edberg Earth & Space Sciences Division Discipline Specialist & Jet Propulsion Laboratory Coordinator for Amateur California Institute of Technology Observations Pasadena, CA 91109 U.S.A. Charles S. Morris Telecommunications Science & Associate Discipline Engineering Division Specialist Jet Propulsion Laboratory Warren Morrison American Association of Variable Data Recorder Star Observers (AAVSO) Cambridge, MA 02138 U.S.A. Thomas R. Williams AAVSO Data Recorder Michael J. Weiner Earth and Space Sciences Division Data Reduction Assistant Jet Propulsion Laboratory 1985-86 Mary L. Firth Earth and Space Sciences Division Data Reduction Assistant Jet Propulsion Laboratory 1986-88 Elizabeth La Vite Earth and Space Sciences Division Data Reduction Assistant Jet Propulsion Laboratory 1988-89 ________________________________________________________________________________ II. PRINTED ARCHIVE The format of the printed archive is described in Table II. Table II. Description of Printed Archive ________________________________________________________________________________ Heading Description ________________________________________________________________________________ ALL TYPES OF DATA Date(UT) Decimal date of the time of observation. For photographs this is the middle of the exposure. Trailing zeroes are often mere space-fillers. AON# Amateur observation network number, a unique reference number assigned to each observation. VISUAL APPEARANCE m1 Total magnitude of the comet. A colon indicates that the given magnitude has lower than usual precision. A > indicates that the comet was fainter than the given magnitude. MM The magnitude estimation method was one of four types: B - Bobrovnikoff method S - Sidgwick or In-Out method M - Morris method V - In focus telescopic (as with variable stars) or naked eye estimates (made with or without defocusing using corrective eyeglasses). See Edberg (1983) for details of the first three methods. A question mark indicates an unknown method. Chart Source(s) of comparison star magnitudes: (number < 179) Specific chart with V and/or visual magnitudes in the American Association of Variable Star Observers (AAVSO) Variable Star Atlas (Scovil 1980). (variable star designation) Variable star comparison chart pub- lished by AAVSO, British Astronomical Association (Tirion 1981), or Royal Astronomical Society of New Zealand (RASNZ), or AAVSO charts with V magnitudes (specially checked by R.H. Stanton, private communication). The latter were distributed by the IHW. A letter following the variable star designation identifies the specific chart used. (numbers) Smithsonian Astrophysical Observatory (SAO) Catalog (S.A.O. Staff 1966) star number, or another catalog's number. AA Chart from the AAVSO Variable Star Atlas (Scovil 1980). AAVSO Unspecified AAVSO source. CZ List of white (B-V < 0.5) stars selected by J. Hollan of Copernicus Observatory & Planetarium, Brno, Czechoslovakia (private communication). E Atlas Eclipticalis (Becvar 1958). LNES Lampkin's (1972) Naked Eye Stars. M Stellar Atlas by Mikhaylov (1975) using Henry Draper Catalog (HD) magnitudes. NPS North Polar Sequence, published by the AAVSO. RASNZ Unspecified RASNZ source. SA Selected area (Everhart 1984), either numbered or unspecified. SAO Smithsonian Astrophysical Observatory source. SC 2000 Unspecified stars from Sky Catalog 2000.0 (Hirshfeld and Sinnott 1982). USNOC United States Naval Observatory Photoelectric Catalog (Blanco et al. 1968). Occasionally, combinations of sources are listed, e.g., SA47SAO, SPER 16, AA NPS, AACZORI, etc. Additional sources were used by a small number of observers for which little or no information was supplied. Coma size Coma diameter [arcmin]. For an elliptical coma the major and minor axes are given. DC Degree of condensation, a qualitative measure of the brightness profile across the coma. Values from 0 to 9 indicate increasing degrees of condensation from diffuse to stellar. See Edberg (1983) for details. Tail Length of a tail [deg]. In the printed version additional tails are listed as notes. PA Position angle [deg] measured north through east. In the printed version additional tails (and fans) are listed as notes. DRAWINGS Scale Scale in minutes of arc per millimeter. Drawings lacking a scale are sometimes included. VISUAL APPEARANCE AND DRAWINGS Ap, Ins, f/, Aperture size [m], type of instrument (see below), focal ratio, Pwr(s) and magnification(s). Type of instrument: B - Binoculars C - Cassegrainian EY - Naked eye JB - Jones-Bird M - Maksutov N - Newtonian R - Refractor SC - Schmidt-Cassegrainian SN - Schmidt-Newtonian The Jones-Bird design is described by Jones (1957) and by Bird and Bowen (1979). On a few occasions the stated telescope characteristics do not seem to match the telescope type listed, both as supplied by the observer. In the case of fast Schmidt-Cassegrainians an auxiliary positive lens was probably used as a telecompressor (focal reducer) and a rather fast Cassegrainian (f/10) is probably a Schmidt-Cassegrainian. DRAWINGS (continued) DurM Time (min) spent to execute the drawing. VISUAL APPEARANCE AND DRAWINGS (continued) Lim Limiting magnitude of stars visible to the naked eye. The letters C, M, T, or Z refer, respectively, to city lights, moonlight, twilight, or zodiacal light interfering with the observation. PHOTOGRAPHY FL, f/, Ap Instrument focal length [m], focal ratio, and aperture [m]. Listed are the effective focal length and effective focal ratio used. A note follows giving the nominal characteristics of the instrument if auxiliary optics were used in making the image. FOV Computed field of view for a 24 x 36 mm frame. Larger format emulsions are identified in the notes. ExpM Exposure time [min]. Emulsion Type of emulsion. ISO ASA/DIN speed of the emulsion. Hyp "Y" indicates a hypersensitized emulsion, "C" stands for an exposure with a cooled-emulsion camera; otherwise an "N". Gdng Type of guiding (methods explained in Edberg 1983): C - computed offsets to telescope drive M - by micrometer O - cross hairs on central condensation S - sidereal-rate drive or guiding on a star T - cross hairs tangent to coma X - cross hairs on a coma with no condensation Id/Typ IHW- or observer-assigned number and type of image on file: C - contact print N - negative P - enlarged print S - slide T - transparency VISUAL APPEARANCE (continued) DA The observer's dark adaptation (Y = yes, N = no). A few observers gave the time spent dark adapting; times greater than or equal to 10 minutes were assigned a Y, shorter times an N. ALL TYPES OF DATA (continued) Site Observing site identification number (cf. Sec. IV). Observer(s) Name(s) of observer(s). Additional observers are indicated in notes. Notes Comments, if any. ________________________________________________________________________________ III. FITS KEYWORDS IN THE DIGITAL ARCHIVE The FITS keywords include both the FITS standards and the table exten- sion option. They are described separately in Tables III-VI. Table III. Keywords for All Types of Data ________________________________________________________________________________ Keyword Description ________________________________________________________________________________ SIMPLE = T / THIS IS A FITS FILE BITPIX = 8 / BITS PER PIXEL NAXIS = 0 / NO IMAGE DATA ARRAY PRESENT EXTEND = T / THERE MAY BE STANDARD EXTENSIONS OBJECT = 'ooo...oo' / NAME OF OBJECT FILE-NUM= 8nnnnn / UNIQUE FILE IDENTIFICATION NO. DATE-OBS= 'dd/mm/yy' / DATE OF MIDDLE OF OBSERVATION (UT) TIME-OBS= .ttttt / TIME OF MIDDLE OF OBSERVATION (UT) DATE-REL= 'dd/mm/yy' / DATE OF PUBLIC RELEASE DISCIPLN= 'AMATEUR ' / IHW DISCIPLINE LONG-OBS= 'ddd/mm/ss' / EAST LONGITUDE OF OBSERVING SITE LAT--OBS= 'sdd/mm/ss' / LATITUDE OF OBSERVING SITE SYSTEM = '8nnnttii' / OBSERVING SYSTEM CODE OBSERVER= 'ooo...oo' / NAME OF OBSERVER SUBMITTR= 'sss...ss' / NAME OF SUBMITTER OF DATA SPEC-EVT= s / SPECIAL EVENT FLAG ________________________________________________________________________________ Table IV. Keywords for Visual Appearance Descriptions ________________________________________________________________________________ Keyword Description ________________________________________________________________________________ DAT-FORM= 'ASCII ' / FORM OF DATA DAT-TYPE= 'VISUAL MAG. EST.' / TYPE OF DATA ELEV-OBS= eeee / ELEVATION OF OBSERVING SITE (METER) INSTRUME= 'iii...ii' / TYPE OF INSTRUMENT USED APERTURE= a.aaa / APERTURE SIZE (METER) FRATIO = ff.f / FOCAL RATIO POWER = ppp / MAGNIFICATION ORIGIN = 'JET PROPULSION LAB' / TAPE WRITING INSTITUTION COMMENT ccc...cc : END XTENSION= 'TABLE ' / TABLE EXTENSION BITPIX = 8 / BITS PER PIXEL NAXIS = 2 / 2-D MATRIX NAXIS1 = 71 / NO. OF CHARACTERS PER ROW NAXIS2 = 1 / NO. OF ROWS PCOUNT = 0 / NO RANDOM PARAMETERS GCOUNT = 1 / ONLY ONE GROUP TFIELDS = 16 / NO. OF FIELDS PER ROW TTYPE1 = 'MAG. EST. METHOD' / VALUES: B=BOBROVNIKOFF, M=MORRIS, S=SIDGWICK TBCOL1 = 1 / STARTING COLUMN TFORM1 = 'A1 ' / FORMAT TNULL1 = '? ' / MISSING VALUE TTYPE2 = 'COMA MAGNITUDE' / TOTAL MAGNITUDE (GIVEN AS ALPHANUMERIC TBCOL2 = 3 / STARTING COLUMN STRING, SINCE 1ST COL. CAN TFORM2 = 'A5 ' / FORMAT BE > SIGN, WHICH IMPLIES TNULL2 = '-99.0 ' / MISSING VALUE UPPER LIMIT) TTYPE3 = 'MAGNITUDE COMMENT' / INDICATES UNCERTAINTY IF VALUE IS : OR ? TBCOL3 = 8 / STARTING COLUMN TFORM3 = 'A1 ' / FORMAT TNULL3 = ' ' / MISSING VALUE TTYPE4 = 'CHART NO.' / USED FOR COMPARISON STARS (SEE PRINTED CROMME- TBCOL4 = 10 / STARTING COLUMN LIN ARCHIVE OR TFORM4 = 'A7 ' / FORMAT INT'L. COMET QTRLY. TNULL4 = ' ' / MISSING VALUE FOR EXPLANATION) TTYPE5 = 'COMA DIAMETER 1' / CIRCULAR COMA DIAM. (OR MAJOR AXIS, ELLIPTICAL TBCOL5 = 18 / STARTING COLUMN COMA) TFORM5 = 'E5.1 ' / FORMAT TUNIT5 = 'ARCMIN. ' / UNIT TNULL5 = '-99.0 ' / MISSING VALUE TTYPE6 = 'COMA DIAMETER 2' / MINOR AXIS, ELLIPTICAL COMA TBCOL6 = 24 / STARTING COLUMN TFORM6 = 'E5.1 ' / FORMAT TUNIT6 = 'ARCMIN. ' / UNIT TNULL6 = '-99.0 ' / MISSING VALUE (OR CIRCULAR COMA) TTYPE7 = 'DEGREE OF COND.' / DEGREE OF CONDENSATION TBCOL7 = 30 / STARTING COLUMN TFORM7 = 'I1 ' / FORMAT TNULL7 = ' ' / MISSING VALUE TTYPE8 = 'LENGTH OF TAIL 1' / TAIL LENGTH (1ST TAIL) TBCOL8 = 32 / STARTING COLUMN TFORM8 = 'E5.2 ' / FORMAT TUNIT8 = 'DEGREE ' / UNIT TNULL8 = '-9.00 ' / MISSING VALUE TTYPE9 = 'P.A. OF TAIL 1' / POSITION ANGLE OF TAIL (1ST TAIL) TBCOL9 = 38 / STARTING COLUMN TFORM9 = 'I3 ' / FORMAT TUNIT9 = 'DEGREE ' / UNIT TNULL9 = '-99 ' / MISSING VALUE TTYPE10 = 'LENGTH OF TAIL 2' / TAIL LENGTH (2ND TAIL, IF SEEN) TBCOL10 = 42 / STARTING COLUMN TFORM10 = 'E5.2 ' / FORMAT TUNIT10 = 'DEGREE ' / UNIT TNULL10 = '-9.00 ' / MISSING VALUE TTYPE11 = 'P.A. OF TAIL 2' / POSITION ANGLE OF TAIL (2ND TAIL, IF SEEN) TBCOL11 = 48 / STARTING COLUMN TFORM11 = 'I3 ' / FORMAT TUNIT11 = 'DEGREE ' / UNIT TNULL11 = '-99 ' / MISSING VALUE TTYPE12 = 'LENGTH OF TAIL 3' / TAIL LENGTH (3RD TAIL, IF SEEN) TBCOL12 = 52 / STARTING COLUMN TFORM12 = 'E5.2 ' / FORMAT TUNIT12 = 'DEGREE ' / UNIT TNULL12 = '-9.00 ' / MISSING VALUE TTYPE13 = 'P.A. OF TAIL 3' / POSITION ANGLE OF TAIL (3RD TAIL, IF SEEN) TBCOL13 = 58 / STARTING COLUMN TFORM13 = 'I3 ' / FORMAT TUNIT13 = 'DEGREE ' / UNIT TNULL13 = '-99 ' / MISSING VALUE TTYPE14 = 'LIMITING MAG.' / MAGNITUDE OF FAINTEST STAR VISIBLE TO NAKED EYE TBCOL14 = 62 / STARTING COLUMN TFORM14 = 'E4.1 ' / FORMAT TNULL14 = '-9.0 ' / MISSING VALUE TTYPE15 = 'SKY INTERFERENCE' / LIGHT INTERFERING WITH OBSERVATION TBCOL15 = 66 / STARTING COLUMN (C=CITY LIGHTS, M=MOONLIGHT, TFORM15 = 'A4 ' / FORMAT T=TWILIGHT, Z=ZODIACAL LIGHT) TNULL15 = ' ' / MISSING VALUE (NO INTERFERENCE) COMMENT VALUE EQUAL TO : IMPLIES UNCERTAINTY IN FAINTEST STAR MAG. TTYPE16 = 'DARK ADAPTED' / WAS OBSERVER DARK ADAPTED? (Y=YES, N=NO) TBCOL16 = 71 / STARTING COLUMN TFORM16 = 'A1 ' / FORMAT TNULL16 = ' ' / MISSING VALUE END ________________________________________________________________________________ Table V. Keywords for Drawings ________________________________________________________________________________ Keyword Description ________________________________________________________________________________ DAT-FORM= 'NODATA ' / FORM OF DATA (NO DATA RECORDS) DAT-TYPE= 'DRAWING ' / TYPE OF DATA ELEV-OBS= eeee / ELEVATION OF OBSERVING SITE (METER) INSTRUME= 'iii...ii' / TYPE OF INSTRUMENT USED APERTURE= a.aaa / APERTURE SIZE (METER) FRATIO = ff.f / FOCAL RATIO N-POWER = n / NO. OF MAGNIFICATIONS USED POWER = ppp / MAGNIFICATION : MAG-LIM = m.m / MAGNITUDE OF FAINTEST STAR VISIBLE TO NAKED EYE PLTSCALE= ppp.p / PLATE (DRAWING) SCALE (ARCSEC/MM) DURATION= ddd / TIME FOR MAKING DRAWING (SECOND) ORIGIN = 'JET PROPULSION LAB' / TAPE WRITING INSTITUTION COMMENT ccc...cc : END ________________________________________________________________________________ Table VI. Keywords for Photographs ________________________________________________________________________________ Keyword Description ________________________________________________________________________________ DAT-FORM= 'NODATA ' / FORM OF DATA (NO DATA RECORDS) DAT-TYPE= 'PHOTOGRAPH' / TYPE OF DATA ELEV-OBS= eeee / ELEVATION OF OBSERVING SITE (METER) PRNCPLFL= p.ppp / PRIMARY, UNMODIFIED INSTR. FOCAL LENGTH (METER) TELEFL = t.ttt / EFFECTIVE FOCAL LENGTH (METER) APERTURE= a.aaa / APERTURE SIZE (METER) FRATIO = ff.f / FOCAL RATIO FOVLENGT= ff.f / COMPUTED FOV ASSUMING 135 FORMAT (DEGREE) FOVWIDTH= ff.f / COMPUTED FOV ASSUMING 135 FORMAT (DEGREE) PLTSCALE= ppp.p / PLATE SCALE (ARCSEC/MM) EMULSION= 'eee...ee' / TYPE OF EMULSION ISO = 'aaaa/dd ' / ISO (ASA/DIN) HYPERED = 'hhh...hh' / HYPERSENSITIZATION TREATMENT TEMP-HYP= tt / HYPERSENSITIZATION TEMPERATURE (CELSIUS) TIME-HYP= ttt.t / HYPERSENSITIZATION TIME (HOUR) TEMPEMUL= tt / COLD CAMERA TEMPERATURE (CELSIUS) DEVELOPR= 'ddd...dd' / DEVELOPER USED TEMP-DEV= tt / DEVELOPING TEMPERATURE (CELSIUS) TIME-DEV= ttt / DEVELOPING TIME (SECOND) GUIDING = 'ggg...gg' / GUIDING METHOD EXPOSURE= eeee / EXPOSURE TIME (SECOND) IM-ID = 'iii ' / IMAGE IDENTIFICATION NO. IM-TYPE = 'iii...ii' / TYPE OF IMAGE ON FILE ORIGIN = 'JET PROPULSION LAB' / TAPE WRITING INSTITUTION COMMENT ccc...cc : END ________________________________________________________________________________ IV. LIST OF OBSERVERS AND OBSERVING SITES Listed in Table VII are the observers and their observing sites as supplied to the IHW. The number preceding the site coordinates corresponds to the Site column in the data listings. In some cases the geographic coordinates were estimated by the Discipline Specialist. Occasionally different sites received the same coordinates because specific coordinates could not be found. Following the coordinates and altitude [m] is the Discipline Specialist's sub- jective estimate of the precision of the coordinates. Especially large values indicate that the estimate was made with an available map or atlas which may not have shown the place named by the observer. The country code is explained in a separate appendix. Table VII. Observers and observing sites ________________________________________________________________________________ Observer Site Longitude Latitude Altitude Estimated Country No. [m] Accuracy Code ________________________________________________________________________________ Adamoli, G. 1 010/00/00 +45/00/00 5 deg 7 2 012/00/00 +45/30/00 1 deg 7 Aerts, L. 1 004/44/00 +51/00/00 15 1 arcmin 29 4 004/44/00 +51/08/00 25 1 arcmin 29 Aleynikov, A. observing site unknown Arbour, R. 1 001/14/49 +51/07/13 122 0.1 arcsec 15 Bohme, D. 1 012/01/15 +51/09/05 169 1 arcsec 23 Bortle, J.E. 1 286/15/42 +41/34/18 122 0.1 arcmin 16 Bottger, B. 1 008/26/24 +48/59/24 116 0.01 deg 25 2 008/28/12 +48/51/00 400 0.01 deg 25 3 008/31/58 +48/51/20 406 1 arcsec 25 Bouma, R.J. 2 006/39/12 +53/18/36 0 0.1 arcmin 46 4 006/01/24 +43/58/30 735 0.1 arcmin 4 5 006/00/00 +53/00/00 1 deg 46 Bus, E.P. 2 006/39/12 +53/18/36 0 0.1 arcmin 46 4 006/01/24 +43/58/30 735 0.1 arcmin 4 Campos, J.A.S. 2 031/06/20 -29/37/30 119 1 arcsec 13 Cardiel, N. 1 357/04/00 +40/45/00 1005 1 arcmin 14 2 355/52/15 +40/17/12 575 1 arcsec 14 Castino, R. 1 007/12/10 +44/57/04 627 1 arcsec 7 Cavagna, M. 2 009/11/36 +45/49/30 854 0.1 arcmin 7 5 007/20/00 +46/10/00 1800 1 deg 7 Chernis, K. observing site unknown Clark, M. 1 116/04/20 -32/07/18 274 1 arcsec 26 Cluyse, L. 1 003/25/30 +50/58/06 14 0.1 arcmin 29 Comello, G. 3 006/24/30 +53/08/24 5 0.1 arcmin 46 4 006/01/18 +43/58/48 728 0.1 arcmin 4 Conte, G. observing site unknown DeYoung, J. 1 282/53/32 +38/44/32 9 0.1 arcsec 16 3 282/56/01 +38/55/17 93 0.01 arcsec 16 4 281/45/32 +37/58/01 151 0.1 arcsec 16 Dietrich, M. 1 010/02/54 +51/15/12 380 0.1 arcmin 23 Dilsizian, R. 1 286/13/06 +41/23/59 296 1 arcsec 16 Edberg, S. 4 242/19/12 +34/22/54 2287 1 arcsec 16 12 243/30/00 +32/49/00 1372 1 arcmin 16 Fabre, R. 1 202/04/12 +21/37/00 3 1 arcmin 76 3 204/32/00 +19/50/00 1 arcmin 76 Fabrizio, M. 1 011/56/00 +44/33/00 6 1 arcmin 7 2 011/45/00 +44/03/00 681 1 arcmin 7 Feijth, H. 1 005/48/48 +53/10/54 0 0.1 arcmin 46 2 006/01/24 +43/58/30 735 0.1 arcmin 4 Ferrin, I. 2 288/52/37 +08/37/35 1880 1 arcsec 17 Gallego, J. 1 357/04/00 +40/45/00 1005 1 arcmin 14 2 356/07/00 +40/15/00 2 deg 14 3 355/52/15 +40/17/12 575 1 arcsec 14 Genebriera, J. 2 354/30/00 +41/41/00 1060 1 arcmin 14 Glassett, W. 1 243/38/42 +33/54/00 322 1 arcmin 16 Glowinski, C. 1 008/16/00 +50/00/00 100 1 deg 25 Gomez, A. 1 357/04/00 +40/45/00 1005 1 arcmin 14 Gomez, T.L. 1 357/04/00 +40/45/00 1005 1 arcmin 14 2 359/30/00 +39/26/00 1 deg 14 Gozzoli, E. 1 011/00/00 +44/30/00 120 1 deg 7 Green, D.W.E. observing site unknown Guryanov, S. observing site unknown Guthier, O. 1 008/03/24 +49/57/48 250 0.1 arcmin 25 Hale, A. 1 242/11/48 +34/22/18 2408 0.1 arcmin 16 2 242/00/30 +34/16/54 1525 0.1 arcmin 16 5 240/58/49 +34/48/03 1615 1 arcsec 16 8 240/52/42 +34/42/12 1750 1 arcsec 16 9 242/18/30 +34/22/48 2290 0.1 arcmin 16 11 243/30/24 +32/49/18 1370 0.1 arcmin 16 16 243/15/42 +34/13/06 2225 0.1 arcmin 16 29 249/21/36 +32/15/18 800 0.1 arcmin 16 Hasubick, W. 1 010/44/00 +48/02/00 620 1 arcmin 25 Haver, R. 2 012/03/36 +42/16/48 340 0.01 deg 7 3 012/04/12 +42/04/12 300 0.01 deg 7 4 013/12/36 +41/57/36 1845 0.01 deg 7 Hayashi, A. observing site unknown Izquierdo, J. 1 357/04/00 +40/45/00 1005 1 arcmin 14 Jones, A. 1 173/14/04 -41/19/07 15 1 arcsec 48 Kammerer, A. 1 008/21/12 +49/00/06 115 0.1 arcmin 25 2 008/29/00 +48/51/24 400 0.1 arcmin 25 4 008/20/00 +48/08/00 900 1 arcmin 25 Keitch, G.S. 1 357/14/30 +51/21/48 21 0.1 arcmin 15 Knight, S. 1 289/18/27 +44/12/10 191 1 arcsec 16 Knyazyuk, N. observing site unknown Koch, B.O. 1 010/44/00 +48/02/00 620 1 arcmin 25 Koch, V. 1 010/44/00 +48/02/00 620 1 arcmin 25 Korth, S. 1 006/50/54 +51/11/36 45 0.1 arcmin 25 Kourimsky, M. 2 015/36/00 +50/42/00 725 1 arcmin 35 Kuipers, G. 1 006/23/42 +53/13/42 2 0.1 arcmin 46 Lieder, F. 1 011/49/00 +50/47/00 325 1 arcmin 23 Linder, J. 1 008/15/56 +48/56/00 110 1 arcsec 25 3 008/31/58 +48/51/20 406 1 arcsec 25 4 008/30/59 +48/47/37 720 1 arcsec 25 5 008/27/04 +48/49/21 622 1 arcsec 25 Lipski, P. 1 013/48/25 +51/02/45 120 0.1 arcsec 23 Luga, M. 1 015/19/55 +51/37/05 120 0.5 arcmin 11 Machholz, D. 1 238/06/00 +37/04/00 1024 0.1 deg 16 Maraziti, A. 1 017/00/00 +38/54/00 0 0.1 deg 7 2 016/36/00 +38/54/00 350 0.1 deg 7 Maydik, A. observing site unknown Meozzi, D. 1 012/18/50 +42/09/20 250 1 arcsec 7 Merlin, J.C. 2 004/23/40 +46/49/20 455 1 arcsec 4 3 006/55/36 +43/44/54 1270 0.1 arcmin 4 Mikuz, H. 1 014/04/33 +45/56/44 730 1 arcsec 35 Milani, G.A. 1 011/50/00 +45/25/00 30 1 arcmin 7 3 011/40/00 +45/50/00 600 1 arcmin 7 4 011/30/00 +45/52/00 1300 1 arcmin 7 Moeller, M. 1 010/43/46 +53/51/38 22 1 arcsec 25 2 010/50/18 +53/59/06 8 1 arcsec 25 Mormil, V. observing site unknown Morris, C.S. 1 242/19/12 +34/22/54 2287 1 arcsec 16 2 243/13/00 +34/15/00 2286 2 arcmin 16 3 240/54/34 +34/44/50 1631 1 arcsec 16 4 249/16/06 +32/25/00 2545 1 arcsec 16 5 249/14/00 +31/57/00 1036 1 arcmin 16 6 242/00/30 +34/16/40 1524 1 arcsec 16 7 241/17/03 +34/34/28 1006 1 arcsec 16 8 242/24/00 +34/24/00 2408 1 arcmin 16 9 241/42/10 +34/16/25 488 1 arcsec 16 10 241/45/00 +34/17/24 524 1 arcmin 16 11 242/03/00 +34/21/00 2134 1 arcmin 16 12 243/30/00 +32/49/00 1372 1 arcmin 16 Morrison, W. 2 281/33/48 +44/13/54 240 0.1 arcmin 21 3 281/36/00 +44/12/54 200 0.1 arcmin 21 Nassr, J. 1 120/34/00 +16/24/39 1507 1 arcsec 50 Nesterov, Yu. observing site unknown Nolle, M. 1 010/09/00 +48/26/00 560 1 arcmin 25 O'Meara, S.J. 4 287/28/30 +42/21/57 110 0.1 arcmin 16 Paradowski, M. 2 022/56/12 +51/22/16 171 1 arcsec 11 Parisio, R. 2 009/29/16 +45/44/15 1800 2 deg 7 Pearce, A. observing site unknown Pedraz, S. 1 355/52/00 +40/38/00 0.5 deg 14 Poitevin, P. 1 005/09/06 +50/56/36 50 0.1 arcmin 29 4 005/31/00 +51/12/00 50 1 arcmin 29 Portela, A. 1 357/04/00 +40/45/00 1005 1 arcmin 14 Remo, S. 1 009/18/52 +45/41/27 343 1 arcsec 7 Ridley, H.B. 1 357/15/42 +50/55/21 59 1 arcsec 15 Ripero, J. 1 357/04/00 +40/45/00 1005 1 arcmin 14 Rodriguez, D. 1 357/04/00 +40/45/00 1005 1 arcmin 14 Rossi, L. 1 013/07/00 +43/26/42 505 0.1 arcmin 7 Sabia, J.D. 1 284/19/56 +41/35/47 399 1 arcsec 16 2 287/28/50 +43/16/41 393 0.1 arcsec 16 3 284/19/50 +41/30/44 439 1 arcsec 16 Sanford, J. 1 243/16/46 +33/29/02 1329 1 arcsec 16 Sanz, A. 1 357/04/00 +40/45/00 1005 1 arcmin 14 Schambeck, C. 1 011/07/05 +48/12/03 540 0.01 arcmin 25 Scholten, A. 1 006/03/30 +52/06/54 17 0.1 arcmin 46 2 006/07/18 +52/11/54 7 0.1 arcmin 46 Seargent, D. 1 151/29/37 -33/21/02 30 0.1 arcsec 26 Serov, V. observing site unknown Shirokov, A. observing site unknown Sicoli, P. 1 009/14/27 +45/47/32 271 1 arcsec 7 2 009/13/37 +45/52/55 1182 1 arcsec 7 Solodkin, V. observing site unknown Spratt, C.E. 1 236/49/12 +48/15/00 9 0.01 deg 21 2 236/46/48 +48/18/00 9 0.01 deg 21 Stomeo, E. 2 012/24/00 +45/24/00 3 0.1 deg 7 Sventitskiy, V. observing site unknown Tregaskis, T.B. 1 145/06/26 -38/11/06 110 1 arcsec 26 Troiani, D.M. 1 271/00/00 +42/30/00 299 1 deg 16 Underhay, E. observing site unknown van de Weg, R.L.W. 1 006/45/36 +52/17/42 15 0.1 arcmin 46 5 013/58/18 +46/40/36 511 0.1 arcmin 28 van der Laan, T.A. 1 007/12/06 +53/04/48 2 0.1 arcmin 46 van Loo, F.R. 1 004/42/48 +51/06/24 10 0.1 arcmin 29 3 006/01/24 +43/58/30 735 0.1 arcmin 4 4 005/50/00 +44/06/00 1700 0.1 deg 4 Velasco, P. 1 356/15/00 +40/20/00 1 deg 14 Ventura, F. 1 014/25/44 +35/54/21 85 1 arcsec 44 Villa, M. 1 011/56/00 +44/33/00 6 1 arcmin 7 2 011/45/00 +44/03/00 681 1 arcmin 7 Zanotta, M. 1 009/00/00 +46/00/00 2 deg 7 2 006/45/00 +45/59/00 700 1 arcmin 7 3 006/48/00 +45/59/00 1322 1 arcmin 7 Zanstra, W.T. 1 006/52/54 +53/19/24 0 0.1 arcmin 46 3 007/23/00 +47/14/00 1306 0.1 arcmin 18 Zische, E. 1 014/25/20 +51/06/56 330 1 arcsec 23 2 014/25/57 +51/02/34 335 1 arcsec 23 3 014/27/00 +51/11/00 3 deg 23 ________________________________________________________________________________ ACKNOWLEDGEMENTS D.W.E. Green, and J.E. Bortle were very helpful in supplying advice and information on many aspects of cometary magnitude estimates and the visual appearance. R.H. Stanton made photoelectric checks on several AAVSO comparison star fields. J.A. Morgan, A. Hale, R. Moore, M. Morrow, J.D. Sabia, J. Sanford, C. Spratt, D. Seargent, E.P. Bus, M. Muciek, J. Hollan, A. Milani, J. Campos, K. Churyumov, G. Keitch, H. Ridley, G. Sule, J. Rendtel, and many other obser- vers served as collection points and forwarded much of the data to the Lead Center. M. Geller and R.M. West provided good advice and encouragement. With- out M. Aronsson's programming and patience the presentation of these data would not have been possible. REFERENCES Becvar, A. (1958). Atlas Eclipticalis 1950.0 (Czech. Acad. Sci., Prague), 32 charts. Bird, T. and Bowen, A.V. (1979). Telescope Making, No. 3, p. 14. Blanco, V.M., Demers, S., Douglass, G.G., and Fitzgerald, M.P. (1968). "Photo- electric Catalog: Magnitudes and Colors of Stars in the U, B, V and Uc, B, V Systems," Publ. U.S. Naval Obs., 2nd Ser., Vol. XXI (U.S. GPO, Washington, D.C.). Edberg, S.J. (1983). The International Halley Watch Amateur Observers' Manual for Scientific Comet Studies, JPL Publ. 83-16 (Jet Propulsion Labora- tory, Pasadena). Everhart, E. (1984). Sky Telesc. 67, 28. Hirshfeld, A. and Sinnott, R.W. (1982). Sky Catalog 2000.0, Vol. 1: Stars to Magnitude 8.05 (Sky Publ. Corp., Cambridge, MA, and Cambridge Univ., Cambridge U.K.), 604 pp. Jones, R.T. (1957). Sky Telesc. 16, 548. Lampkin, R.H. (1972). Naked Eye Stars (Gall & Inglis, Edinburgh). Mikhaylov, A.A. (1975). Stellar Atlas (Nauka, Moscow). Scovil, C.E. (1980). The AAVSO Variable Star Atlas (Sky Publ. Corp., Cambridge, MA), 178 charts. S.A.O. Staff (1966). Smithsonian Astrophysical Observatory Star Catalog (Smith- sonian Inst., Washington, D.C.). Tirion, W. (1981). B.A.A. Star Charts 1950.0 (British Astron. Assoc., London), 5 charts.