Ocmttation@Newsteiter
Volume II, Number 15 March, 1982
Occultation Newsletter is published by the International Occultation Timing Association. Editor and Compositor: FI. F. DaBo11; 6 N 106 Hhite Oak Lane; St. Charles, IL 60174; U.S.A. Please send editor,ia1 matters to the above, bUt send address changes, requests, matters of circulation, and other IOTA business to IOTA; P.0. Box 596; Tinley Park, IL 60477; U.S.A.
FROM THE PUBLISHER times; perhaps in the future we can reconsider it.
FOr subscription purposes, this is the first issue One or two more volunteers could also help with the of 1982. calculation of our graze predictions, if they have access to a relatively large computer which can read o.n.'s price is $1.40/issue, or $5.50/year (4 is- and write standard 2400-foot magnetic tapes, prefer- sues) including first class surface mailing. Back ably can read and punch cards, and compile FORTRAN. issues through Vol. 2, Nn. 13, still are priced at In principle, all the predictions could now be com- only $1.00/issue; ;ater issues @ $1.40. Please see puted at USNO, but in practice, manual work is still the masthead for the ordering address. Air mail needed to include double star data, and with the shipment of Uuv. back issues and subscriptions is asteroidal occultation and star catalog (especially 45¢/issue ($I.80/year) extra, outside the U.S.A., for lunar eclipses) work which I need to do, I do Canada, and Mexico. not expect the double star data to be automated this year. Two computors lost access to the machines IOTA m«nbership, subscription included, is $11.00/ they had been using late last year, which caused year for residents of North America (including Mexi- some problems with the calculation and timely dis- co) and $16.00/year for others, to cover costs of tribution of predictions for the first half of 1982. overseas air mail. European and U. K. observers should join IOTA/ES, sending DM 20.-- to Hans-j. Hith the he\p of the word-processing capabilities of Bode, Bartold-knaust Str. 8, 3000 Hannover 91, Ger- an Apple-ll computer, we also hope to start the task of producing a comprehensive manual of occultation man Federal Republic. observation. Volunteers with access to Apples are IOTA NEWS sought for possible help with this project, to enter the current papers, and some of the early work to- David Id. Dunham wards producing a rough draft of "the manual", onto diskettes which we can edit to produce an up-to-date Unfortunately, we are again rushed to distribute comprehensive product. this issue, so that you might receive it in time to use finder charts, and other information, about IOTA incorporation is progressing. We are starting asteroidal occultations which occur during the sec- the process of completing the IRS forms to obtain ond half of March. Many new asteroidal occultations tax-exempt status. described on p. 198, and other work have kept me busy, so that again I have not had time to write I thank the many observers who have sent me reports articles about grazing occultations or new double of their timings of occultations during the total . stars, and had to curtail the article on observa- lunar eclipse of January 9. Of special interest tions of asteroidal occultations. I hope that I can were the observations made at both the northern and finish those articles for inclusion in the next is- southern limits of the occultation of Z.C. 1110 = sue, which we plan to distribute early in June and D Geminorum = Wasat during totality. As far as I which will have information and charts of the star know, this is the first time that grazes of the same field to be occulted by the moon during the total star have been observed at both limits of the same lunar eclipse of july 6. occultation. Paul Maley and Charles Herold traveled farther than anyone else has for a graze, from Hous- The next issue will be the Idst of Volume II. A few ton, TX, to Dagupan City, Philippine Islands, at the months after it is distributed, I hope that we can northern limit. They made 14 timings from two sta- distribute an index to both Volumes I and II, per- tions. About 11 more timdngs were made from Rosales haps with the first issue of Volume III. Volun- by an independent expedition led by Ernesto Calpo of teers are sought who might help with the preparation PAGASA, the Philippine Weather Bureau. At the of the Volwe II index; write to me at P.0. Box southern limit, David Herald observed from the cen- 7488, Silver Spring, MD 20907, U.S.A., if you are tral Australian desert about 150 miles east of Ayres interested in this. Most oiPthe work for an index Rock. He had to travel over hundreds of miles of for Volume I was completed long ago, but originally dirt roads with taperatures ranging up to 46° C. I had wanted to include with it a comprehensive Unfortunately, clouds prevented observation of the stellar index. The latter is too ambitious at this second half of the graze, but one good disappearance point, so rather than delay things further, we will was timed. My analysis of the observations shows plan not to have a stellar index for the first vol- (Continued on page 200) 198
MORE PLANETARY OCCULTATIONS DURING 1982 1ished in the Leningrad Ephemerides of Minor Planets for 1982, similar to the calculations he performed Andrew Lowe and David Id. Dunham to find the additional asteroidal occultations dur- ing 1981 published in o.n. 2 (12) 164. Although Lowe has manually compared the SAD catalog with as- planetary perturbations were neglected, accurate teroid ephemerides generated with Keplerian fomulae calculations by Dunham again showed that Lowe's se- using the precision osculating orbital elwents pub- lections were quite good. Again, the searches were restricted to minor planets with triad LULU > ;xuj uj ajo o Q)o Q) 0 0 o o d) aj o Q) O 7?' aj diameters between 100 and 200 km which COO CLCj~~~ e e~ C~OC\J C~— C~0 m m mOLA C~m~ · ~uj 0~~~ might not have been included in Gordon =q= 2'n~Q¢—~—ZQ~o~m«o~~o~
"& Notes about observational attempts for 0 some of the occultations which already
a CJ have occurred are given in the article 2 qo~m~Smcnu)%%cn¢o¢o ~%cnLnmmc"j~mqom~
dictions for all events have been computed using which occur on the following dates: Mar. 9, March Leningrad (I.T.A.) elements, usually taken from the )5, June 24, July 5, July 17, July 19, Oct. 31, and E.M.P. for 1981. New orbital elements given in the Dec. 29. When the ephemeris differences are larger, 1982 E.M.P. have been used for the occultations by they are indicated in the notes about some of the (137) Meliboea and (159) Aemilia. The differences events which are given below. between the Herget and the I.T.A. predictions are not significant — less than 0!'6 for the path shift Feb. 17: The star's 9.8-mag. companion, 5" away, and less than 3 minutes of time — for the events was not predic ted to be occulted from the earth's surface, missing by about 4" to the F- - c")Oc')u)Nr~O~LO~~N cvmwlc^nU)oocvc')&)Ln(DLoNmLn north. The path for the primary was = · c")oU)Lc^T¢'j.u?<·c'j~=)~c'jN~onoNLDmLc^nomc'qw G.) O predicted to miss the surface by 0!'4, Lbj Q) ~ 1" and the time error could exceed 5 minutes, 30 the electric recording of a grazing occultation with occultation could occur in virtually any part of portable equipment on January 21St. The star was North Ameirica. AstrOmetry 2 or 3 months in advance 4.5-mag. Z.C. 2498 = E Ophfuchi. A 20-cm Schmidt- would be valuable for refining this inaccurate pre- Cass was used with a 30" diaphragm; with a sun diction. A special astrometric opportunity will oc- alt. of -7°, the sky background was quite bright. cur on Sept. 15, when Ema will be near opposition Heavy dew reduced the paper in the chart recorder to and g degree north of SAD 146191. something resembling wet tissue paper, so it had to be abandoned. The data were collected at 1/25th- IOTA NUS (Continued from page 197) second intervals and stored in a small computer. The circulating buffer was comanded to stop Just that there fs no significant correction to the polar after the graze ended, but for some unknown reason, radius of Watts' datum near zero latitude libration, it continued for ano0er 90 seconds. The last four an important result for our analysis of solar events were saved. Several visual timings were made eclipse observations for detemining small varia- by members of the Tampa Amateur Astronomical Society tions of the solar radius. This means that, to Zed by Tom Campbell, and by a couple of Univ. of FL about O:i accuracy, the solar radius deteminations students. An expedition in eastern FL led by H. we make from the solar eclipse observations are made Povenmire was also very successful. Due to thick in an absolute sense, not just relative to each oth- fog, it was possible to get only one timing at an er. Paul Haley used an unguided, undriven C-90 cam- B-station effort near Tallahassee led by Chris Hunter and me. . eratwicetowhilephotographthe starthewasstar'sbehindtrail,lunarwhichmountains.is brokenIt will be published in the 1982 issue of Sky and Tele- If your astronomical society is not listed already ·cDpe. in one of the directories of such organizations, you might write asking for forms from: GALL Publica- A short account of our efforts to record the occul- tions, Box 6666 Station A, Toronto, Ontario MSW lX4, tatlon of Nunki by Venus is given in Sky and Tele- Canada and/or AndrC Heck, clo ESA Satellite Tracking ·cope 63 (2) 207. I will try to write a longer ac- Station, Apartado 54065, Madrid, Spain. ~ count for a future issue of o.n. In the meantime, we continue to use the video equipment for lunar dc- 3rian Loader, 273 Scott St., Blenheim, New Zealand, cultations, almost routinely now. It is well-suited has designed forms for recording timings of eclips- for field use and can be set up rather quickly. On es, occultations, and transits of the Galilean sat- March 2, I traveled with two other observers to ellites of Jupiter. Jay Lieske, jet Propulsion Myrtle Grove, ng, just south of Wilmington, to ob- Laboratory, says that timings of these events, es- serve a graze of 6.8-mag. Z.C. 726 by a 50% sunlit pecially eclipses, will be of use for the Galileo moon. we met several NG observers there, and by the mission. time all observing site arrangements had been made, time was becoming short. I arrived at njy site less Starting this year, the graze predictions have been than 25 min. before the graze began, yet I was able computed with USNO version 80F, which is easier to to set up the 20-cm Schmidt-Cass and the video use than the other versions, although some of the equipment, make adjustments, and begin recording star catalog reference data for southern stars is the graze a minute before the first disappearance. lost. However, the ACLPPP profiles continue to use I recorded twelve events; a visual observer 400 feet version 78A, and this is what observers should use to the north had 16. Eight minutes after the graze for finally setting up. One word of caution: Ver- ended, the equiµent, still partly connected but sion 80F inciudes Perth70 catalog data, whereas powered off and stowed safely, and the other two ob- 78A does not. If there is a large (over 0'.'4) VPC servers and I were driving north, to a pre-arranged given on your ACLPPP profile for southern-declina- site Just north of Warsaw, NG, 100 km north of tion stars, especially ones of medium brightness, Nrt1e Grove, since 95 minutes after the ZC 726 version 80F has probably used Perth70 data so that graze ended, a graze of 97 Tauri would begin at the the limit predictions will be a better representa- new sIte. lde arrived there 12 minutes before the tion of where the extreme part of the moon's mean appointed time, and had the video equipment set up limb will be than ACLPPP. But sometimes version 80F In time for that graze, but even a 5th-mag. star uses SAO-G.C. data instead of Z.C. data, in which could not penetrate the clouds which now veiled the case, the ACLPPP and version 78A probably will be moon. The exercise nevertheless proved the utility better. This is rather infrequent and can be spot- of the video setup. We had a little more time to ted by large (greater than O:'S) probable errors of _ reach Rocky Mount, another 100 km farther north, for star's declination listed in the limit prediction athere,thirdthegraze,cloudsof were6.2-mag.so thickZ.C. 736,that butthe moonwhen wecoulot heading. not be seen. We relaxed and played back the tape of I was moved to a different office than expected, so the first successful graze made at Myrtle Grove a the extension given at the bottom of p. 196 of the few hours before. last issue is wrong. My home telephone is 301, 585-0989 and my work number is now 301, 589-1545, Peter Chen, University of Texas, Austin, has sent me ext. 603 or 326. 0 diagrams of the electronics for the portable PhOtOm electric occultation system which he has designed. OBSERVATIONS OF ASTEROIDAL OCCULTATIONS AND APPULSES I don't know what the arrangements for duplication of the system (fabrication) will be, and plans for David IQ. Dunham the photometer head were not included. We'll pub- lish more about it when we know. Reports of attempts to observe occultations of stars by asteroids, at least when clouds do not prevent In a related development, Glenn Schneider, Universi- observation, should be sent to me at P.0. Box 7488, ty of Florida, Gainesville, made the first photo- Silver Spring, MD 20907, U.S.A., and to Gordon Tay- 201 lor, H.M. Nautical Almanac Office, Royal Greenwich possibility of a substantial satellite, but neither Observatory, Herstmonceux Castle, Hailsham, Sussex occultation was confirmed by a second observer. BN27 IRP, England. If any possible occultation events are timed, it is recommended that you use the (9) Metis and SAD 184474, 1981 February 12: Metis ILOC lunar occultation report form, writing the is of special interest due to the possibility that number and name of the asteroid at the top of the it has a large satellite; see o.n. 2 (ii) 123. As- form; but do not send a copy of the report to ILOC, trometry by Penhallow and by Klemola indicated a since they collect only lunar occu)tation timings. path at 0!'75 north, over central Zanbia. Unfortun- ately, it rained in Salisbury, Zimbabwe; several Due to a shortage of time, only a few events will be observers in South Africa, well south of the expect- discussed here. More will be described in the next ed path, reported no occultation. A telegram sent issue. In general, only events of wide interest for 'to an astrononjy club on Mauritius was received after which some astrometry was obtained, or events where the appulse. either primary or secondary occultation timings were reported, will be described here. (48) tbris and SAD 118852, 1981 March 19: Klemola's astrometry of Mar. 10 Indicated a path 0!'27 south (739) Mandeville and SAD 118438, 1980 December IQ: crossing the southwestern Ij.S.A., generating consi- Observations of this occultation were noted in o.n. derable interest. K1emola provided fainter refer- 2 (ii) 143, but I did not even know the star then. ence star positions to other astrometrists from his Some information about the event has been obtained large-field AGK3R-reduced plate. Plates taken at from a japanese publication sent by Toshio Hirose. New Mexico State University a few days later indfca- Shio Oikawa translated the article, "Pursuing the ted a path about a diameter farther north, and a Minor Planets' Shadow," by Masahiro Ogasawara. One plate taken with the 61-inch USNO telescope at Flag- observer reported a 5 or 6-second occultation, cor- staff, AZ, the night before the event predicted the responding to a chord of about 100 km, about the occultation nearly exactly, placing the center of ~_ expected diameter of the asteroid. But an observer the path at about 0!'09 south. In spite of low alti- less than 40 km north of him reported no occulta- tude, a 99%-sunlit Moon only 7° away, and cloudy thetion,Besselianwhile anotherplane) aboutnearly160simultaneouslykm to the northtimed(ona J skies over western Washington and most of the south- western U.S.A. and part of British Columbia, the ~ - M-second occu)tation. The observations indicate following observations of the occultation of the a rather flattened shape for Mandeville, with the 9.0-mag. star were made: Observer Location AE!S!Ll Longitude W. Latitude N. Height. Disappearance Reappearance Tom Lutz Pullman, Wash. 30 cm 117° 09' 10" 46" 43' 44" BOO m jjh 40" 37' jjh 40/' 52' Neil Laffra S. Langley, B.C. 20 cm 122 36 44 49 03 12 82 m 11 41 13.8 11 41 18.9 Leigh Palmer Burnaby, B.C. 20 cm 122 56 05 49 16 55 285 m 11 41 16.1 11 41 22.2 The observations at the two stations in British Co- tion times were not estimated or applied. The ob- lumbia were confirmed by other observers. Both of servations are plotted in Fig. 1. The chord length them reported that the star began to fade about O% at Pullman was 196 km, considerably larger than the before the complete disappearance time given above. 149-km diameter given by TRIAD. But the assymetric The times are UTC, detehnined from voiced calls onj chords, nearly on top of each other, obtained at the tape recorders recording kl\dV time signals. Reac- B.C. sites indicates a very irregular shape, probab- ly with more of a slope on the disappearance side, MO which could explain the observed fading by prolonged Fresnel diffraction. With essentially only two m m chords and an irregular shape, a meaningful diameter of Doris' outline can not be detemfned. My guess 0 " is that Doris was elongated In the direction of mo- tion, with Pullman near the center of the path, so that the mean diameter is less than the Pullman ~ Y chord length, but more than the TRIAD value. _ "40" . 0 202 dieted nominal path. The astrometry for the F?b. 8 ANOTHER PLUTO APPULSE everit indicated a substantial south shift, which would put the path for the Jan. 11 occultation south David Id. Dunham of the nominal path, probably over Algeria and the eastern Mediterranean. Also, since the predicted On TAU Circular 3674, M. P. Candy, Perth Observato- central duration was gS, it is very unlikely that ry, notes a possible Rccuitat!on of a 13th-magnitude the Oulu event was an occultation by the asteroid star, at 1950 RA. 13 58 43 , Dec. '6° 43:7, by itself, which would have to be grazing. I have not Pluto on 1982 April 15.067, with a miss distance of received any other reports; the Oulu observation was 0!'35. I calculate a miss distance of 0:'7 also to announced on an I.A.U. card. the south, at 4h U.T., when the appulse will be vis- ible from the Amerfcijs and Atlantic between longi- (344) Desiderata and B.D. +45° 1520,1982 February S?: tudes 20° E. and 130° hi.; a 63% sunlit waning moon Plates exposed by Penha11ow on Jan. 28 indicated a will be up east of 70° KL Since Charon will be substantial ephemeris south shift from the EMP 81 south of pluto, it is less likely that it will oc- path, such that it might cross the north-central U. cult the star. Measurement of a plate taken by S.A. Klemola obtained a plate exposed at Lick con- Klaola in 1973 gives a star position 0:4 north of necting the star and asteroid on Feb. 1, but prob- Candy's position, which would increase the miss dis- lems with the plate measuring engine delayed the tance by that amount. Results of any more astrome- plate reduction until Feb. 5. This refined the path try (Klemola hopes to' expose a plate late this · to 0':63 ±0:'07 south, putting the path over Lake Win- month) will be announced in a future tau Circular, nipeg, Manitoba. Although weather was uncertain and and distributed to appropriate IOTA members if the twilight would be a prob]«n, I telephoned the result results show that an occultation is likely. A cen- to Richard Bochonko at the Univ. of Manitoba. The tral occultation would last about 2 minutes with a path also should have crossed central Scandinavia l-mag. drop. and the western U.S.S.R., passing near Leningrad and northeast of Moscow. I tried to telephone Gordon PLANS FOR UPCOMING ASTEROIDAL OCCULTATIONS Taylor the result to disseminate to European obser- vers, but discovered that he had left that day for David KL Dunham Israel, probably to try to observe the occult.ation of SAD 162831 (= Z.C. 2867) by Venus on Feb. 7; see The recorded messages for asteroidal occultation ~~" p. 198. In an earlier telex message, I had request- prediction updates can no longer be obtained from ed that he notify observers in the area about the the Little Rock, AR, telephone number, now discon- Venus occultation. For Desiderata, I telephoned nected, given in o.n. 2 (13) 182 and in Sky and Hans Bode, asking him to notify Scandinavians. I Telescope 63 (I) 63. However, they can still be then checked our foreign weather service, which said obtained from the Chicago, IL, number, 312, 259- a large NOrth Atlantic storm was headed for Scandi- · 2376. Berton Stevens updates these messages, but navia, with better prospects for clear skies in the he can not do so when he is not home. Consequently, U.S.S.R. It was by then Saturday morning there. if you call on a weekday, you might wait until after Don Trombino, who had organized a tour for the re- 8 pm Central time to be sure to obtain any news cent Siberian eclipse, gave me the home telephone which I may have relayed to him that day. It is of Alexander Kova11 in Moscow. We telephoned him, possible that updates might be obtained by telephon- and he said that he would disseminate the predic- ing The Astronomical Unit in Little Rock at 501,771- tion. Although Silver Spring was over I" south of 0940, but it is not known if the recorded message the newly-predicted track, I decided to attempt it. machine will be connected to that number in order to A large patch of cirrus blanketed the area at the obtain the information when the store is closed. time, so I traveled to Gaithersburg, MD, about 40 km to the northwest, where I set up my 25-cm reflector Most of us will miss the occultation of 0 Aurigae by under clear skies. The 10.7-mag. star was at the (250) Bettina discussed below, but it is interesting threshold of visibility and could not be effectively to compute how frequently occultations of stars as monitored due to glare from the full Moon 31° away. bright as, or brighter than, this star by asteroids Craig Patterson was able to monitor the star using as large as, or larger than, Bettina occur. If we a 40-cm Cassegrain reflector, f/13.5, at the Grundy accept Brian O'Leary's calculation, published in Observatory at Lancaster, PA, and saw no events. On Science several years ago, that any given main-belt Mar. 20, the star will be a little brighter, and asteroid will occult one SAD or AGK3 star somewhere there will be no moon, so the observation should be on the Earth's surface, on the average, each year, possible with smaller telescopes, probably down to then I calculate that occultations as good as the 15 cm aperture. upcoming one by Bettina occur only every 106 years. But this is based on Bettina's diameter of 211 km LETTER TO THE EDITOR from TRIAD, which assumes a dark C-type albedo, al- though in TRIAD it has an uncertain CMEU classifica- The University of Arizona tion. David Thoien, Univ. of' Arizona, reports that Lunar and planetary Laboratory recent colorimetry shows that it is an M-type aster- oid, so that it should be much smaller, as was the I would like to cali your attention to the "Plane- ' case for (216) Kleopatra, an occultation by which tary Appulses and Occultations," published in The was observed in 1980 October; see o.n. 2 (ii) 140. Observer°s Handbook — 1982 of the Royal Astronomical If Bettina has a diameter of 150 km, occultations of Society of Canada. The table indicates that coordi- stars as bright as e Aurigae by asteroids this large nates are for epoch 1950, whereas they actually are occur about every 34 years. However, radiometric for 1982. Maybe a note in Occultation Newsletter observations made during the last year have shown would be useful. that the M-type asteroids in the outer part of the asteroid belt have low albedoes, similar to C-type \4. klisniewski asteroids. A new classification has been proposed 203 for them, pseudo-M or P. Unfortunately, the semi- close asteroid (angular size 0!'09) will occult 8.4- major axis of Bettina's orbit is near the Hungaria mag. SAD 113745 at about 4ho UT, probably for ob- gap; the closer M-type asteroids all have typical M servers in the southwestern U.S.A. The event will high albedoes, while most of those farther away are have occurred by the time you receive this, but I P-type. Tholen thinks that Bettina is probably a will have distributed my own predictions of the regular M-type, but Ed Tedesco, another who has event beforehand to potential observers. Kracht worked with the recent observations at jet Propul- notes that the asteroid is %012 late in its orbit, sion Laboratory, believes that at Bettina's dis- derived from recent photographs, and has applied tance, it is probably P. Unfortunately, as far as .this correction to the EMP 8] orbit which he used either knows, no radiometric albedo measurements for his calculations. I don't know if It will be were made of Bettina during the recent opposition. possible to obtain last-minute astrometry to improve Tholen and David Morrison, Univ. of Hawaii (con- the prediction; the motion is 55:4/day and a central tacted by Wayne Warren), said they would check into . occultation will last at most 254. the possibility of having suitable observations made before the occultation to determine Bettina's albedo Mar. 20, (344) Desiderata: Klemola's astrometry for and diameter. If this is done before the event, I the February 8th occuitation, based on 3 Lick Obser- will notify Paul Maley or Jorge Polman.of the re- vatory exposures taken on February 1, indicate that sult. the path for the Mar. 20 occultation will be 0':54 Id, over Alaska and Hawaii. However, no astrometry has In the meantime, Gordon Taylor has predicted that an yet been done on the star, and the motion on Mar. 20 even brighter star, 1.9-magnitude e Sagittarii = is nearly due north-south, almost exactly perpendi- Kaus Australis = SAD 21009] = FK4 689, will be oc- cular to the Feb. I motion, so an uncertainty of culted by the 175-km C-type asteroid (804) Hispania several tenths of an arc second remain. Attempts at on 1983 October 23. Although Hispania is smaller more astrometry will be made, mainly to assess the than Bettina (assuming optimistically that its type prospects for Hawaii, but western Canada and the is P), the brighter star makes sUch events rarer, northwestern U.S.A. may still have a chance. occurring only once every 141 years. The predicted ~- path of the occultation, using the EMP 1982 orbit, Mar. 20, (?50) Bettina: The controversy about Bet- will cross northern Australia in daylight, just tina's size is discussed above; hopefully, observa- north of Fiji and the Samoa Islands shortly after tions of this occultation will answer that question L- sunset, and near Christmas Is. south of Hawaii, near finally. Four exposures taken by Penha1low on Feb. the equator. The path using Herget's orbit is 2:'87 2 indicate a correction to the ephemeris of 0!'09 S farther south, crossing Antarctica and the surround- ±0:'3, with a negligible correction to the time. Al- ing oceans. Rather poor-quality astrometric obser- though no correction is available for the star, the vations made in 1977 and 1979 favor EMP 1982. but occultation almost certainly will occur in Brazil, only slightly. More astrometry is needed to improve with no possibility of d northward shift for daytime the prediction, and soon. This year, Hispania has viewing from North America. Klemola, who will be a favorable opposition on March 15 near the celes- busy with other events discussed below, will measure tia) equator around jjh right ascension. Unfortun- good reference star positions for other astrome- ately, the prospects for astrometry next year are trists to use for the final prediction. A major dismal, at least for the Northern-Hemisphere obser- problem for accurate astrometry is the star's vatories upon which we have almost exclusively de- brightness and rather close duplicity; a very long pended for occultation improvement astrometry so focal-length telescope will be needed to minimize far. The declination of Kaus Australis is -34?4 this problem; the 20-inch twin astrograph at Lick is and during Hispania's opposition in 1983 June, the not sufficient. Unfortunately, the telescope at asteroid will be south of -40°. Astrometry this Allegheny Observatory will not be available for this year from the Northern Hemisphere would certainly be effort, but we hope that one of the other large re- of some use. But Gordon Taylor and I would be in- f'ractors in the eastern U.S.A. can be used for the terested in possible sources of good Southern-Hemi- needed astrometry. Penha11ow's small update to Bet- sphere astrometry for the event during 1983. tina's orbit also indicates that the Mar. 3 occulta- tion probably occurred near the nominal path in I wonder if we are especially lucky to have aster- northern Africa, and not at all in Europe. ¢· oidal occuitations of two very bright stars in two successive years, or are the probabilities a little Mar. 21, (2) Pallas: The Lowell Observatory re- better than O'Leary has indicated? I suspect that quested astrometry at Lick for this event, and Klem- " the latter may be partly the case, but my own figur- ola obtained plates in late Feb. The event has a ing indicates that it is off by, at most, a factor very small magnitude drop, requiring good conditions of 2. Also next year, we hqve the occultation of and photoelectric observation to detect, and the 4.9-mag. I Vulpeculae by (2) Palias, which should nominal path crosses an astronomically uninhabited be visible from the U.S.A.; a star this bright part of the Pacific Ocean. However, Klemoia's as- should be occulted by one of the 4 largest aster- trometry gives a path shift of 1!'4 east and time oids only once every 60 years. Also next year, correction of only 0¢!12 late, so an occultation might Taylor has found that 5.6-mag. 14 Piscium will be occur in the western Hawaiian islands. The path occulted by (S}) Nemausa in the U.S.A. on Sept. I], predicted by Larry Wasserman, Lowell Obs., using the so one does not have to wait too long for a reason- same dua, goes centrally over the Hawaiian Islands. ably close asteroidal occu1t"ation visible well with Between Mar. 21 and 31, radar observations of Pallas binoculars, if not the unaided eye. Notes about will be attempted with the Areceibo radio telescope, some of the more immediate upcoming events are given with hopes of detecting the satellite suspected from below. speckle interferometry. Photoelectric light curves are sought during this time to help interpret the Mar. 15, (433) Eros: Rainer Kracht, Pinneberg, Ger- analysis of the radar data. man Federal Republic, predicts that this small but 204 Mar. 23, (386) Siegena: Astrometry for this event Although I do not now plan to go to Brazil for the also was requested by Lowell, and Klemola's prelimi- occultation by Bettina on the 20th, I may be away nary prediction gives a path shift of K'29 north and all that weekend to record a lunar grazing occulta- a correction to the time of +5.8 minutes, virtually tion of a 4.9-mag. star in the Midwest. Prediction identical to the prediction from the EMP 81 orbit, updates still will be available from the Chicago which clearly is favored over the Herget orbit used recorded telephone message noted above, and possibly to compute the nominal path. Klemola's uncertainty also from Lowell Observatory at 602, 774-3358; I 'Is estimated to be ±0!'3 since the objects were near will keep in touch with astrometrfsts, and will be opposite edges of his Feb. 25 plate. He plans to prepared to calculate'such prediction updates as may obtain another plate to give an accurate last-minute be needed, during the time I am away from Silver prediction. Spring. PLANETARY OCCULTATION PREDICTIONS FOR 1982 Notes about rndividual Events David Id. Dunham Apr. 13: SAD 78094 is NY Gminorum, an irregular supergiant with a magMtude range of 0.6. - This is a continuation of the article in o.n. 2 (13) }78, which includes tables of all of the planetary June S: SAD 162993 is Z.C. 2891. and asteroidal occultations predicted to occur dur- ing 1982, with the exception of the new events list- Nov. 2: SAD 148612 is Z Erldani, an RR Cr8 variable ed by Lowe and me in this issue. The rest of this with a magnitude range of 1.6 and a period of about article consists of notes for the events in the 80 days. earlier article, and of world maps, regional maps, and finder charts for events in both articles, for Nov. 22: SAD 76017 is ADS 2633; separate predic- specific occultations which will occur during the tions are given in the table for the components, next few months of 1982. which are separated by 3!'6 in p.a. 339°. ~ / / 6· I .. J)-))))')))",l. . . " ?r ' ' " I I _1,"" j:\d",:> : J " "/" m jT ," "; "' ,, " 'evm»: : " 't--'· :-—~,_ "" '7'5Ilj'\7j:. - jc',i'"";' i:i.&.'!jS' ~ -:!g'::,,j,":!!ji: :; 'I')._._ _j 4'i,Z!j':iy '"""-'E:'i"ii::,,! -"' ' ZUy SAD 162831 by Venus 1982 Feb 7 SAD 60710A by Aeria 1982 Feb )7 SAD 112400 by Meliboea 1982 Feb 24 r)))):, "/js"))j -:"=4':m"?' '\:e\:\J\\, : :'ti 1/ . .j . y:' "" ' - " """" "- --" --1¶t ' '7 f . 'I))" <'~ , :O GE"""" "i'ii!::'.e:',:'};y ; ,/:"zgZ^" SAD 112446 by Meliboea 1982 Mar 3 SAD 162917 by Myrrha 1982 Mar 9 SAD 77636 by Eunomia 1982 Mar 30 Y aim !*2 3 21) (344) OESICEMTA d) ·« 17!7 % DIAJETER !47 m - o:cn "' ,,)y . '- ~,, "" C", L \' """ ' G"": , / - " , " ' rC'·' J.rj ""~-~, ,, , ? "- k·f r - "'. —-~^gs? ." Gj \ "t \—~~,,_ , %. X '" " \_ 0 "' g, %l,">) , " . ·, >¥ ' ' "", r L g'Gj W ' / ' y ' I ·' 'L --\ N B N P W ' " .' \ C A Q) , / /" X d" \ X "" \ M " " \ I / ' D' . ,Yy, A / .·" " " _"7",_";j! ~-q / i : '5 ' 'F"Z'fV'' :"X /"[· " '1 .1 '~- ,i"$A:,::.-13J° -taj -ItO ::"-100 \g:y'j-,-90 --aj -70 .,,-6lj , -scf LCNGITUDE L- EAiE7ERIS SURGE - E:'P Bi 19,2 4 IEj (1"rfi) LUCINA EE) "17'2316 DIANETU 153 KM - 0:13 . ,., '=::,.4 ... ..^N..=:·- i— -"' "'"i . :z"g':a^_. '))Z))))), '"U'"'"")"""" SAD 78094 by Eunomia 1982 Apr 13 ~ .LG[Z?':!:¥:'"?i"" — ,". r -3s:,x ' ¶p|t . -·-:=-'~ -" ' ,,A Iky" ' "" " ~ 1":;=!=·'-T!" ry is"' . :· " 7·' '3' ' " _ :I"'"}" :»-," '" :¶ " " yElg_= ' -20' -;0 0 !0 20 . 30 4!j IS)' %" " " LQK1.( :LEE EPH:7ERIS SJ-RC.E ' 1?11" !981 +17° 2516 by Lucina 1982 Apr 18 206 * . 19E32 3 20 (25j) EETI INA 5AO 58636A · 8 AUR(GA€ ' . diapeter 211 km - ij;'n z'":""LT"^ j.).)j)jj ),:=g',, JOJJU!i"'"" "- i1j)7jj ' ·+ " W " ^^ ~-----=— ,';: I - .' --e="' ' '^$'1± ·SH ><.:1 +--—·—- S""' i sE. r-'" "ej-.. ,s " "' H \· "I ,j¢-r^" k,'-~r\:n-. ' ":"_""c"""!r=-—±_ !j_""';. . '<'E'j:'""'""" SAD 96799 by Tercidina 1982 Apr 18 -laj' -i 10 -iaj -gj -ebo -m 60" i L0NGIT(KE EFH1PER15 5CLHCE - FFRGET )'""')'""i "~ ]982 3 20 (250) BET1 Ina SAD 5EJ636A b e AUKIGAE . U.))'-:". " DIAIEIER 21! KM " o:ii SAD 145044 by Xanthippe '82 Apr 18 15"-€y n r——-—--u/) n, 6 C/.EIN ,'" "~=~,. , 4 Y / 7 N I a _, 0 ZSni " " '"~-j ,"n=·"" 5 -I). q N i " / °"' ' / - ' ~ ' rj ,-T '?1_'__0.? g " OUj>- ~ I Ch~" t".'--.Sf-±- ~ 1982 3 23 l3f.l,i) SIEGENA CI) 'Cl6' 1468 D1AME'ER 203 KM - c:i I " "'T" i, ,)"))))))))))I))"'#"' ..~:J'O"£3'""'!'"i'"^"""'|}C">' SAD 61101 by Herculina 1982 Apr 27 ")')j)',,)!)))'~O,j',,, !)"J'"/'-)/ ,,::"o"M""9'""""e:"'2&'o,f'?"":"' " C8:, "As? 'A==<"" I "i I ~. -130' -iaj -Ito · too --fu -lX) -'If! la¢3 lTucjt: EFH]'CR15 S2'A?CE - HERC! I ~ — """HhtEg!d,|:µ|>!:__ °' D: ", "· ,, ,9: ' O ·. 'g q ~~ .. . r, · +24°1572 by Flora 1982 Apr 29 ,jQ5 — 0 '·D "· ·DO dl!). · 0 , ·8@, ,'" 0: .""""' · ...... ,, "' 9: " 0 ,.. 0 " :" b, n , D U 0 " F ' ' ' ' O 0 . "' , . ' · ' " D " O ,y 7 , n7? '* 3 ,jO: · . ' '. ,.· Q?·p-0 "' " t·ctiocdos'e . ) 0 t,;]:)..r'i\.., " ° ' ~" 'G & " ° " ° · d0 ' 0 ,'r · ' SO .· Q & 3 , O O 0 7OS ·' '' · , · "e "6 - 3 D G) '0" aP % "" CC Di) ' 0 C,; ' P ? ¢j ' A!) O " 8 0 ' ® -" ,"""\ " . : 4'" 0 D O D , C) O3 D 0 n. j "\, ' " "°'")':)'!i)"")")":j,!)))': E' . CI g g¥'" 'I) 'C) " 1'· · "., ., " ' b . 0 0 "S -S O (I) O P "' . O D CjP D 2 cb O 'i "ANDS '- ?. · " °0 Q 0 00 · SX ",,PhNoR ,:'" ... *f , , . r · D O 0 " OO ' ', ', . '-—' - D ,' 0 .4" m jO I " DOt ·1 b I 0 Icb n : .I'· 0 . , ,, 4 2 7'0" "^ 56 SC 52 SO &" "., ./ , " ' 0 4 1992 YFA 23 H SILGENR ® "06° 1468 ' ' "'. ''· " 7! " ' ' 0 ' ,""' ' '~-' -2051615 by Uranus 1982 May 1 Cyu%"$' 0 " "19' 9 , "~~.0 0 · " 0 "· a·j . ¢2". " ." ). "m~= '"""""""""" ""'"" 0 '%:" J'"I'J e 0 . > · 0 ·1% - 0 , . o cj '" pknsj DJ" cxMum'Q·M Q 0 . ' e 0 e 0 e5 'C1¢43Q . " 4 · . 0 " 2r Q:CCD· t , ",., t Q a O¢u0 '' ° ' Am K t' , O · 0 · ocjimm 0 . O D D j)))_))i)|j)j' "I 7cr', 0 B C O 0 · RERENKE5C'MA o'm-" Cbm"9 O ?0 " , D . · : d e ' LI 0 »,n,0 " d tj.uur ""' " O ' 0 '6';/" . O "" . · a I... _.. FT .... U>j ·16 " 0 - 3 ' " · "€ho c"'"=agjT=b d " 0 0 , . VIRGO oam"",D " r,S' a 0 ° , , ,:,:=~a"""" '· . , . " Q " " ° j 9 C 'SWZ C3 <5', D ,>4?9 "tg":::!):g'"' 0 ,is" i i 1 P i i t qS: : ' 1992 6 25 (2!2) HECEA SAD !09515 !982 6 29 (165) LCRELEY SAD 92359 DINETER 228 KM - 0 :! 0 . [)1APETER 133 m " D:O6 45" i 'V—" I "¥ ' §" m t I · '93 L- J_, -,5. O 40 - " t' ' jS: Q" 6"\, !_C' Q " — _ ,2t,,QPj ' ' ,:} D2"'": ^[·te . ~ ~ L I 6 ~ T , ·¶ : 50;'"|, "~~· " " - ' , : " 4 : 30 t3>" " t ,." 1 L '1\ , " " t; E ", 't) " {$'9' V T ~, '"J n " E U _N 1- ' ~ ~ 4 D ',?"\ " ~ "J " G y. · m.ia)'y,:y ' '° _"t'71g e<"r:i:)"" """ ?:? """" ' ,Q+ W -125" -i IS -no" 7 ' ',J}" " 'S ':6" --'"":, . P "" €" ' LCNGI 'REE " ' '" ""^'2'}!A A >'" " EM€PER1S SO.FcCE - FERGET " ,dJ" ;j " ,1 ._ ,%-" '"i :.? :. "<*_,_ "" o?"\,sa% K ~ L_ IQ" 20 3Ci 40 78 60 70" .I gk "~, : ChYGl I UIJE [pfE71EiilS 5')':R(.E - FERGET 1 """"')))))) 0 0 0 , of r"-" SAD 99172 by Harmonia 1982 May 28 p d (I (' , ' "/ " b ' lX " k 0 G X , . I '~" \ ' ' / qC °)1 . .\'""" ·X) · · L) 0 0 6 ~ r' ", """ "¢?b 1I , . A3" t %O "V,-. · i » 0 " CI) V , I . , t X O ""t/" ';'"'"'""iP " C 0 0 t T" 4 ·19 - ' 00 ' / · . 0 Q . ¶ \ a t,) 0 I I . I " »0 " _ (I) · « CI . " 3" · ':. /·/% " L m - "% O V Ob i (3 l ' .i , . , I t? " " I © ·R j . ZS" " D C) ' °12)5¶ ". 0° I e"'";:ysi ' Aries m" L Llj I i 1 . , , LJ k. _ , ' " " " 1 " " " %' I O 0 , ·:, J I j . .. 0 0 0 , .t, "' " % · · % ' . i" D ' ' . e T .. / P 0 "a O O " , ' D . .- 0 _" " ¶ (I) P ? O O 0 · : /' ..- · S " E , -r"1,r · U 0 · µ I re ' i i / ' D -- "" > ° !'"iit/j""i ·15 _QJC O _.L_ _ .L . O , i \ "/ " 22 ;'1' is is }4 12 IQ S I 6 . / - y F_ m2 JUli ?9 165 LIFELEY * 92359 ? · , ~ejaug!E!Ud~ %/ ,". " ! M 'wes ...... _ ... _ Richard Nolthenius " Cetus SAD 109635 by Pandora 1982 Jun 4 \ ' . 210 im 7 7 (56) 1'elete sad 139812 1982 7 20 (405) THIA SAD !61675 » DIAPETER 142 KM - 0:12 DIAPETER 126 KM - 0:13 %"j LONGITUDE _ {J -L· " EFHEFEMS SOURCE m EPP 1980 -"" A-- "" ·- :.X ,, it- "i'] !982 7 16 (410) CFLCRIS SAD 99171 DIAIETER 142 KM - 0:06 " ,"t.j/' '"' " " 4'2['"/" 't "" Kz-:: Ub fs " ':",r ' ° ,gj:': " S , A " " :," \, \\-:/ X,":': ~-"" Z"-:' r - 'L" -e-Onm ' r I ' i < ~ . y ' 9 'Cj?"— SAD }62993 by Nysa 1982 Jun 5 ! 45 — >~ " , 'I cS/. 4:""I 1S_, Y3 > . ' " ''W N ' g T S, _ W ) L W 0 EU 35 V", ,"3 S X- 6-;;.: 7 \, X_ , _ -" - ":Z" 30' ' ")))')'1',""' _ : " 4L~ m W WW ~ 0 N W ,(/"SS Qiz 0 ' ' , m" X,¶ i I i I 1 I J -130' -120 -no moo -90 -80" "'"""" 2?zSpn#'":""' '" LONGITUDE .. ..G .4M_. ' Cf1 ["PTR15 SCXUiCt: - m' J!JU1 SAD ]42233 by Juno 1982 Jun 11 211 . "V m "~ jCf i' .r~A=!i =p<" · "t»")gaz\,,. : .".. CilmA:?b ,i|))))))| u¢i!):,"",i:" /,|)Ujilj-, \ri !:j ] :! j) g ""jjj'j ' Y - , "i-·i"» _~!'-r-'^ ""·'::.";"'7''" I / t "\"-- - 00 -- 7·- -t- / 4"r "" a Pi &_ -p ^c'r "=;=/zT' ' '" - · ~ -- " "' h SAD 100452 by Eva 1982 Jun 13 SAD 138868 by Gyptis 1982 Jun 24 SAD 109515 by Medea 1982 Jun 25 i . " -Wr ph==~ . .0 —. 0 , "' 'I F7l -G ·") -j-m.·",-." :': r --'":))))))))),")) / : )' " -T. t Nr ¢ -4-% J J " b· ~6 , : :"· , ,~L I : i 4 " '\ " "', \ """-)),)::j"'""t -=a, '" SAD 92359 by Lorely 1982 Jun 29 '09°I',))219 by Pandora 1982 Jul 4 SAD 110134 by Emita 1982 Jul 5 % ,, 4;;2A S:·. X . ^ '?1)))/" --t" "))j:)lg.;'°" I)")) '))))))I"" '"|}:,':)^\,a)::: "" ""'a"='Ey"!,:yw' " · ZF5·" "" '-;= SAD 139812 by Melete 1982 Jul 7 SAD 128582 by Sapientia 1982 Jul 8 SAD 212479 by Palma 1982 jul 14 Q12" . '-'jJ'j' ,zn P " , I t?' 7" ..\"_ — ,1)i))'""j 'I))) ""'"R\jf-'x'"" "" j);!'jjj' "y""i'"j)!)" SAD 110836 by Ino 1982 Jul 14 SAD 99171 by Chloris 1982 Jul 16 SAD 94036 by Liberatrix '82 Jul 17 H 212 . m 1:)))7'°"_..-. ijjjjl J))'))" -'y=='"" "' , ,": \" "i"T<="r"':; . ' I "":*z;ES"' SADY{'!i::,::ty197802 by Nysa 1982 Jul 18 SAD 111464 by Artanis· t : 1,982 Jul 19 SAD 161675 by Thia }982 Jul 20 t-'"' ="":1'»~ . ?'y7""""3'z\ ,, , :'g"' "'""'E'"l;)3 )l)):'"') '"J '1' ~- I)' ,)'),)' ' \ .- '"N \,\, -'\ -C:. , G .L'r -.-- V j:):::::|']j:"'" "'·"&E#->" / " -05° 471 by Ino 1982 jul 27 SAD 94827 by" a-j-.Comacfnavy-- -:'"1982 Jul 28 SAD 163787 by iqyrrha 1982 jul 28 I) )' )))!)))))),)" 'jI))""°" ' ,' ?" -Z " , a. 2b T ,9 cl" ~ ~\ ~u , . m ' SAD 139825 by Cybele 1982 Jul 30 "23" 755 by Aspasia 1982 Aug 1 SAD 58847 by Hippo 1982 Aug 4 ' W a ' a ° " b C " D p " ~ . 6 0 0 0 , " 0 D C) 0 0 0 0 · ® O ~O 0 , ,:;;tS'.Ys.,,. . 08 O · 0 o7 e ' 0 " D g D · 0 0 I , 0 0 0 " ' e :. , O . 0 . 0 P (I). , ' · I o 0 " I Jo 00 . m - · " D " UT5H · " I " - m " I :' % U, '99, , B q. , 0 , , F p 0 OO ° e j " · oS . · O 0 'PCGA6U$ t ,) ': " " " '"yi,.'il;)tt4'"" . , 0" '^QU^AJuS m· p ,2 0 · · ° '"id' 'C)°J ""°° : Dx, ..' , ,,· , ,,, " S? , t?" P ' 38" 35 34 r 30, a 25 u 2a2" i , On t+[ 0 Da SAD 127592 by Mrmosyne '82 Aug 29 m2 fug 29 (57) knenosine yi0 |27',92 COUNT OF LUNAR OCCULTATION TIMINGS MADE DURING 1981 q' r 0bserver(s) 1. 2. 3. City State/Province ' Country Observer Observer How many lunar total occul tation I 2 3 1 2 3 timings made in 1981 did you How many of the total were report to: ILOC? .recorded photoelectrlcally? 0 Please provide USNO IOTA? station code(s) Please provide ILOC Other? (specify) Sta/Obs/Te1 code(s) How many of these were reappearances? Send completed coupon to: joseph E. Carroll 4261 Queens Way Minnetonka, MN 55343 U.S.A. "m. m- Notice to IOTA/ES members : After the enclosed issue of O.N. was duplicated, I discovered that Paul Hergct had publi.shed a new oFbit for (156) Xanthippe in the Minor Plane " Circulars in "1979. I computed the circumstances of the appulse with ' SAD, 145044 on April 18 using llercjet's orbita1· data, and find that the ' path is 1!'64 north, and 34'!'6 later than, the EMI' 1981 path which I UScG for my calculations given in O.N. This path misses thc! Earth's surface by 1!'36 to the north. I have reduced 1974 and 1977 observations of Xanthippe using both orbits, and find much better agreement with Herget orbit, which satisfies the data to i':S. Although the path uncertainty is still large enough that an occultation could still. occur near the ·~. EMP 1981 path, such an event will not be observable from Europe, since the closest approaCh actually will occur about 35 minutes later than m} EMP 1981 prediction. · Hence, the Sun Alt. = -2° line on my inap on p. 2( '" will'be nine degrees of longitude farther west, passi.n'j even west of Portugal. Skies would be dark enough at the Canary Islands, but they are probably too tar south for an occultation to take place. 1982 March 26 ' " David W. Dunham P.O. Box 7488 "" Silver Spring, Maryland : " " U. S. A. ^