Occuttau'm@Newsteuer

Volume I, Number 15 July, 1978 The 0ccu)tation News)etter is published by the International Timing Association (I.O.T.A.) Editor and Compositor: H. F. DaBol), 6 N 106 White Oak Lane, St. Charles, Illinois 60174, U. S. A.

SATELLITE OF MINOR PLANET (532) HER- Arizona. Observers in Mexico, Nevada, at the corresponding point, and a 553 CULINA DISCOVERED DURIIIG OCCULTATION and Hawaii also were alerted, and occultation is evident there, with in- Mayne Warren sent a telex mes:age from dications of the fade due to the David hi. Dunham Goddard Space Flight Center to Mt. 's diameter. The observations are Stromio Observatory in Australia (un- consistent with a dynamically possible A satellite of (532) Herculina was fortunately, the message did not get satellite 50 km in diameter and 0':9 or discovered visually, and confirmed through to David Herald, who might 990 km from Herculina projected in the photoelectrically at another station, have alerted observers in Townsvilie, plane of the sky. The southern limit when the asteroid occulted 6.2-mag. Queensland, from which the occultation of the satellite occultation should SAD )20774 on June 7. A finder chart would have been visible). The occulta- nave passed a few km north of Horne, and brief predictions were published tion shadow crossed California's Mo- so the fact that he saw no secondary in the last issue of o.n. A brief ac- jave Desert, where it was timed visu- occultation is consistent. The satel- count of the amateur-professional co- ally by IOTA members Keith Horne at lite should be about 3 magnitudes . operation which led to this remarkable Rosamond (duration )7S3) and James Mc- fainter than Herculina, which was mag. ~ discovery is given below. More infor- Hahon near Four Corners (duration 9.3 at the time. At favorable elonga- mation will be given in articles in 2056). Mike A'Hearn, visiting from the tions, such an object should be de- Nature, Icarus, and Sky and Telescope University of Mary1and,'and Ted Bowell tectable with area scanners or by vis- ()978 September issue). also recorded a 2355 occultation pho- ual or photographic observation tech- toe)ectrica)ly with Lowell Observa- niques; such observations are in prog- The occultation occurred less than ten tory's 42-inch telescope. Fortunately, ress at Lowell. The period of revolu- days after the successful observation observing conditions were excellent tion about Herculina is probably 60 ± of the May ?9 occultation of SAD 85009 and the observation successful in 30 hours. by Pallas, on which astrometrists con- spite of the 25° altitude above the centrated their attention, partly due western horizon (with the sun 9° down Although this is the first confirmed to the fact that the Kuiper Airborne in the east)! Mike A'Hearn set a rec- satellite of a minor planet, a number Observatory was going to attempt it ord which probably will not be beaten of such objects have been suggested by (see OBSERVATIONS OF THE OCCULTATION soon, since he also recorded the oc- previous observations (see FURTHER BY PALLAS, p 156, this issue). The ex- cultation by Pallas on Ny 29. Bo- SUPPORT FOR MINOR PLANET MULTIPLICITY, pected path%cro$sed the Pacific Ocean, well's analysis of the timings gives p. 152). Herculina's satellite was starting off the coast of Mexico and 217 km for Herculina's diameter, in nearly in line with its apparent mo- passing between New Zealand and Aus- good agreement with results from radi- tion, while the object which may be tralia, from which the event would be ometry and polarimetry; the observa- orbiting Hebe was perpendicular to visible in case of a small shift. i tional residuals were only a few kilo- that asteroid's movement. Some special sent copies of IOTA Special Bulletin meters, probably due at least as much observing strategies are recomended as, giving details about the event, to to mountains and valleys on Fkrculina to establish whether the causes of many observers in New Zealand and as to timing uncertainties. The fade secondary are terrestMa1 southeastern Australia. I also sent of the spectral-type M2-III star at or celestial: copies to Lowell Observatory, Flag- disappearance and at reappearance I. Visual observers should observe staff, AZ, and to two observers in lasted a few tenths of a second and in pairs about a km apart, close California, since I said in the bulle- was noticed visually and photoelec- enough to see the same secondary tin, "An improbab?e, but not impossi- trica)1y, as expected (see A,YGULAR DI- occultation but far enough apart ble, 2:'0 north shift would cause the AMETERS OF TO BE OCCULTE3 BY MI- for truly independent observation; M occu1tatiori to be visible from the NOR PLANETS [in #16]). The derived coincidental timings would imply a populous southwestern part of Califor- stellar angular diameter is 0:0029, celestial origin. nia at about llh27m U.T. at about 8° with considerable uncertainty due to 2. Photoe)ectric observers should altitude above the western horizon." the low altitude. also observe visually, if the ex- Two nights before the event, William pected magnitude drop is great Penhallow obtained three astrometric McMahon waited until the following enough to see, either with a guide plates of Herculina and the star at weekend to analyze his tape recording scope or (better, to prevent inad- Quonochontaug Observatory, Rhode Is- carefully before telephoning we the vertently bumping the main instru- land. He reduced his measurements of results. He said that observing condi- ment) with another telescope near- the plates and telephoned me the ob- tions were good at his site, and by. Visual observations can estab- served positions 32 hours before the claimed that the star disappeared com- lish whether dips in the photoe- event. I recalculated the path, find- pletely six times within ± 2 minutes lectric record are due to guiding ing that it would shift 2:'I north of of the main event. During the 6 min- or other instrumental problems, or the nominal prediction; the expected utes that he observed before this in- due to the star's actually disap- path now crossed Arizona (at very low terval, and the 4 minutes that follow- pearing. altitude) and the San Gabriel Moun- ed it (after which he stopped observ- 3. High-speed (usually digital re- tains north of Los Angeles! A plate ing), the star appeared fuzzy due to cording is needed) photoelectric taken d few weeks earlier could have the 'u 8° altitude, but its brightness observations can record the Fres- spotted such a large ephemeris error remained steady. Most of the secondary nel diffraction pattern as the and shown that the probability of the events were quite short, perhaps in- star is occulted by the asteroid. event occurring in the southwestern volving objects too small to occult The diffraction pattern will be USA was good. In any case, I tele- the star at the other stations, but modified by the star's angular di- phoned many IOTA members and profes- one 97 seconds before the primary oc- ameter, and perhaps by close du- sional astronomers interested in dc- cultation had a 4SO duration. The Low- plicity. Hence, if the star's sig- cu)tdtions, throughout California and ell photoelectric trace was examined nature appears.in the diffraction 152

, pattern for a secondary occulta- earth than in June, the magnitude drop mined well enough to predict its fu- ,

P tion, it safely can be assumed to will be nearly as great as for the ture motion, a permanent designation f . be celestial. June 7 event (see the last issue of such as "(532) I" will be assigned. ' o.n., p. 142). It will be important to Since asteroidal satellites are prob- watch all future occultations by minor Addendum received 1978 July 15: t ably common objects, it may be useful planets carefully, to see which types T to record ell negative (miss) observa- of asteroids have the most satellites. james McMahon discusses his historic ? V : tions reported during asteroidal qc- They may provide important clues about observations in a paper, "The Discov- P cultations which are observed some- the formation of the asteroid belt. ery of a Satellite of an Asteroid," t Z where. I have received negative re- Due to greater geographic dispersion, which he distribyted with the July L i ,. ,por·ts of the 'derculina event from ob- amateurs may be more likely than pro- bulletin of the China Lake Astronomi- i" servers in Tokyo, Japan; San Jose, fessionals to discover asteroidal sat- cal Society and which he also used as i i Fresno, birightwood, Glendora, and San ellites, but observations must be made a first draft of a paper to be pre- . Diego, CA; Hcmolulu and Mauna Kea, HI; carefully for confirmation. sented at the Astronomy West '78 joint

1k and Hoden, Australia. The northern convention in San Luis Obispo, CA, g T limit of the Herculina occultation Brian Marsden suggests that the sate1- July 27·-30. All observations, includ- probably passed,about 15 km south of lite be provisionally designated "1978 ing the five extinctions of the star Fresncj,'CA, while the southern limit (532) I," indicating that it is the which he saw and for which there were probably passed just north of Palm- lst satellite of (532) Hercu)irja to be not equivalent observations at the dale, CA, in accord with the miss ob- discovered in 1978. This essentially other stations, are plotted in his di- servations. Herculina will occult a follows the adopted I.A.U. prctice for agram reproduced here. Note that Bo- 7.8-mag. star, probably in South Amer- satellites of major planets. If direct well's observations were teminated 6 lea, on August 22. Since the asteroid observations of the satellite are ob- seconds af'ter emersion from HercUlina, will be nearly 1 A.U. farther from the tained so that an orbit can be deter- just before 1'1cMahon's extinction #6.

/ ,b:je;> / esss/ yXo

C 4 , " "±C

"""'""""""" V , I X ^ . °\ Direction of motion b bb 5 % " . of Herculina > tV 0I A I ' 2b0 k" b,g"g

? He discusses the interpretation of the events might be lost in the noise of Wimer is certain that a miss occurred cbservatiwis, from his statement of the Lowell photoelectric record, there. This is possib1e,·since the 3 June 9, "I would sooner believe that which, as noted above, was terminated observed chords were wei] south of the elephants could fly than that aster- soon after the emersion from Herculi- center of Herculina (more so than in- oids could form into stable clusters," na. McMahon notes that the small aper- dicated in McMahon's diagram). The to Edward Bdwell's statement of June ture he used may have been an advan- Fresno observations imp1y"that the 28, "These two independent observa- tage for seeing the secondary events, true average diameter may be at least tions constitute incontrovertible evi- which appeared as complete to him, a few kilometers less than the 243 km' dence of a secondary occultation for while in fact they may have been deep value derived from the formal solution which the most likely explanation is a partial events. He reported that the satellite of Herculina." McMahon star's image remained steady, but was [Ed: As Dr. Dunham mentioned, McMa- points out that the discovery might somewhat diffuse during an 8·-minute hon's paper was a first draft. The fi- not have been made at all if the truck period centered on the occultation. nal report will be prepared prior to his group used had not failed to start While he observed,-the star's image the Astronomy Nest conventicin, will after they stopped at the site north remained sharp at other times before have improved figures, and will be t of Four Corners from which the obser- and after this interval. He noticed printed in black by photo-offset, vations were made. They did not want haze in the desert air as dawn bright- rather than in the purple ditto of the to use the site due to lights behind a ened after the event, but again, the first draft. Mr. McMahon has agreed to hill a few miles to the west, but symetry is curious. Could a cloud of provide a copy of the final report to their plan to observe instead from a dust, surrounding Herculina somehow each U.S. requestor who includes a location a few miles farther south to diffuse the star's light, or was the stamped (28¢), self-addressed, long. escape'the light pollution was foiled dust only in the earth's atmosphere? (ca. 44 X 9k) envelope (James H. McMa- by the starter failure. At the more In stmnary, there is much to look for hon; 109-P Blandy Ave.; China Lake, CA Southerly location, the SO-km satel- during future asteroidal occultations, 93555). European requestors should lite which produced the secondary oc- which should be carefully observed. make arrangements with H.-J. Bode. Cultation at Lowell probably would not Other non-lj.S. requestors may contact have occulted the star, so that there Note added 1978 July IB: the editor (Mr. DaBo1"4) for further would not have been two independent information.] observations. Fortunately, they were G. Taylor's and D. Dunham's recent an- able to start the truck and return to alyses of the the observation showed " FURTHER SUPPORT FOR China Lake after the observations had that the diameter of Hercu)ina is 243 MINOR PLANET MULTIPLICITY been made. km. The 217 km value computed at Low- ell resulted from a combination of co- Richard P. Binzei McMahon notes that two pairs of the ordinate and program errors. When extinctions he observed', #4 and 6, and these were corrected, they also ob- Paul Maley's observation of an event 2 and 7, were very symetrical with tained 243 km. A new solution for the occurring well outSide the min path respect to the Herculina mid-occulta- satellite gives a diameter of 46 km. of the )977 occultation of the star y tion time. The possibility of their If the albedos are similar, the Am Ceti by the minor planet 6 Hebe was bejng caused by narrow rings is in- would be 3.6, indicating that the sat- initially greeted with much skepti- triguing, but hard to reconcile with ellite probably would be too faint to cism. Because of the experienced Ma- the absence of corresponding observa- detect directly. The new solution in- ley's certainty in his observation, tions at the other sites. Due to the dicates that Fresno, CA was about )0 David Dunham recognized that he prob- low altitude, quick and/or partial km south of the northern limit, but G. ably had observed an occultation by a

..r 153 satellite of Hebe [o.n., i (ii), 1)5-7 ham to propose the idea of satellites this and which are planned for {July '77)]. The question of minor of minor planets, most preferred to the future, and the recent USNO pre- planet multiplicity has been raised rationalize away the secondary events, diction versions, also were discussed. several times previously in astronomi- a?1 by visual observers, as being IOTA plans for observing the 1979 Feb- cal literature but has never gained spurious or due to atmspheric condi- ruary 26 solar eclipse, mainly from much attention. Now in the light of tions. 'locations just inside the path of to- recent occultation observations, mul- tality (see o.n., 1'(14): 144), were tiple minor planet systems are becom- Confirming evidence for the existence described during an A.L.'eclipse ses- ing generally accepted. of minor planet satellites came when sion which preceded the IOTA meetiiig. one of the secondary events observed Minor planet multiplicity was first visually by jim McMahon during the oc- hie now have enough material on hand to conjectured in 1901 by the French as- cultation of a star by 532 Herculina publish two issues of o.n. Some of the tronomer Ch. Andre,l who was struck by on )978 June 7 was in perfect agree- articles mentioned in this issue will the similarity in .the light curves of ment with a secondary event found in be published in issue #16, which may 433 Eros and the-eclipsing variable B the photoelectric record of the occul- be distributed less than a month after Lyrae. This 1ed,him to conclude that tation-.made by Ted Bowell at Lowell this issue. Like issue #12, issue #]6 Eros is actually a double planet sys- Observatory. This event has been rec- probably will not include lists of tem. RecCnt theoretical, work also has ognized as caused by a sate17ite of double stars and grazes observed, but proposed that'624-Hektor is a "binary Herculina, and this object has been will include some of'the text-for the asteroid."2 officially designated 1978 (532) ] in , articles associated with the.lists IAU Circular 3241. In retrospect, published in this issue.; Interestingly, several visual observ- R.ichard.Radick of Prairie Observatory 'Q ers have reported actually seeing Eros in Illinois found that he had recorded The o.n. Volume I index"can not be as dou§7e. During the 1924 opposition photoelectrically a secondary event published until about October, to give of Eros, ii." T. Innes at the Union Ob- during the 1978 May 29 occuitation of time to include the material in issue servatory in johannesburg noted on one a star by Pallas. One other observer #)6. He have decided to break up the night that, as seen through their of the"Pa11as occult2tion recorded a indexing job, which is rather big for 22.5-cm refractor, Eros appeared "bar- possible Secondary event. one person. Volunteers are sought (or like, or similar in appearance to a ams will be twisted) to prepare sec- close double star."3 hi. H. van den Bos If the resulting discovery of a satel- tions of the index concerning, for ex- and hi. S. Finsen, observing with the lite of Herculina allows us to infer ample, double stars, grazes, planets, 56-cm refractor at Johannesburg in that the observations of secondary asteroids, special objects, publica- 1930, noted on several nights near op- events seen during all prior occulta- tion abstracts, erroneous star posi- position, the image of.Etos appeared, . tions of stars by minor planets were tions, and clusters. An author index "certainly a Eigyre±f-eigh,t,-resem- .. , actually due to the pre:'ence of satel- biing that of a 'notched' or nearly is needed. The star-numbers in the lites, then it is necessary to con- double star and graze lists arC being separated double star of about 0:'18 clude that, in order for us to be for- keypunched so that lists sorted in distance."4 Their observations listed tunate enough to have detected them, star number order can be generated by a OR-magnitude difference between the m"iner planets must be surrounded by computer, but volunteers are needed to components, and a period of revolution swarms of such bodies. Furthermore, of 5h17m. go through the associated written ar- since it seems that these Hdies have ticles. I will try to coordinate the been detected during each observed oc- overall indexing effort. USNO Z-nm- Van den Bos and Finsen also.made an . cultation, it indicates that multiple bers will be converted to Xmnumbers " additional very interesting observa-, minor planet systems may be the rule, for the index (see IMPORTANT INFORMA- tion involving.amther minor planet in rather, than the exception. TION REGARDING GW\ZING OCCULTATIONS 1926. While sweeping a zone in search AND USNO PREDICTION VERSI0NS,'p. 155). of new double starsw they found and References measured 0j)c which they could not COMPARISON OF ZODIACAL SUBSETS identify in any atlas. Further re- 1. Estronoinische Nachrichten, 155, 27 OF THE PERTH 70 AN1) SAD CATALOGS. search revealed that the new."double (1901) star" was actually paqlas!5 Van den 2. Physical Studies of Minor Planets, David W. Dunham Bos also stated that he had observed NASA SP-267, p. 155 (1971) Titan to be·doub1e,in )929 and )930 3. Astronomische Nachrichten, 241, 55 From 1967 to 1973, astronomers from (unpublished).' (1931.) Hamburg Observatory, German Federal " 4. Astrcux5mische Nachrichten, 241, 329 Republic, set up'a photoelectric me- ' Only in the last few have ob- (1931) ridian circle at"Perth ObsCwatory, servers had success in observing the 5. MOnthly"Notices of the R.A.S.C., Western Australia, and systematically not particularly rare phenomena in- 86, 209 ('1926) measured accurate pOsitions of 24,000 volving occultations of stars by minor 6."ICarus; 28, 1'33 (1976) stars as part of the Sµithern Refer- planets. In each case where such an ence Star (SRS) program. The density occultation has been observed success- IOTA NEWS is about one star per square degree " fully, thenephave been observations P, south of +5°, but many'. . which support the notion of minor. . David hi. Dunham stars, most brighter,than sixth magni- planet multiplicityb An occultation of tude, were also observe(j between +5° a star by-2 Pallas.in February of 1973 A meeting,tif, the"I0TA officers was and +35°. The average mean error at was observed from three locations near held in Highland'Park, IL, on June 23. the observation is.±,-O:}?. Prup- the shadow"path, and yielded seemingly At that time, the IOTA treasury and er motions were genera17y'deF"ived from confusing results. The observers at records were turned over to John other catalog data, and introduCe fur- the extremeszboth, reported certain oc- Phelps. Although he was named Treasur- ther error at current epochs, but at cultations, while the central observer er last year, the records were not )980, the total mean'"error for Perth" was certain he saw no-occultation at brought up to date and organized we?1 70 stars is expected to average less all. In 1973 October, Harold Povenmire enough to turn over to him until this than 0:'3. The coordinate system de- observed a brief occultation of a star June. An extra $250 was received from fined by Perth 70 is a smoothed FK4 : by 129 Antigone from southern Florida, the organizers of last year's National system with smaller local errOrs than even thougMastrometric measurements Amateur Astrcmomers' convention, which FK4 itself at epoch 197Q.1 made shortly after the event showed was, at final acc,ounting, even more that the main path had passed through successful than expected (see o.n., 1 The SAD catalog relies mainly on.the Colombia, far to the south of Poven- (12), 121). ,. Yale and Albany General (G.C.)"Cat£ mire. LarFy Nadeau and several other logs, with observation epochs aroun'd observers, located well outside the An IOTA meeti® As held June 29 dur- 1930 and 1890, respectively, so the main path of the occultation OF k Gem- ing the Astronomical League's meeting positions in the Perth 70 catalog are inorum by 433, Eros.in ]975, also re- in Madison, WI. Asteroidal occulta- expected to be a big improvement civCr ported brief or "partia1",occulta- tions were a tna.in'topic of discussion. SAD positions. Lunar occultation pre- tions.6 However, even after Maley's 1mprovements.in· the USNO total occul- dictions are currently computed using observation of 6 Hebe, which led Dun- tation predictions which I have made a zodiacal subset ( Iatitudes

4 154

between -6°40' and +6°40', maximum for some of these stars: K00049, mag. proper motions for many zodiacal possible' topocentric ranges for lunar 8.8, Perth 70 mag. 7.9; K00626, 10.7, stars, including all SZ stars and most occuitations) of the. SAD catalog, with 10.0; K07328, 8.2, 7.0; and K07348, (probably all) K-catalog stars, to all Cata taken instead from the Zodia 7.9, 7.3. K07328, at the corrected compile a more accurate and more corn- cal Cata]og2 (Z.C.), N30, FK4S, and rag. 7.0, is the brightest star in the prehensive "XZ" catalog which will su- FK4 for about 14% of the stars. This K-catalog and is row being occulted. persede the SZ (and K) catalogs for "SZ" catalog, ordered by )950 R.A., was The others are SZ stars with poor po- all occultation work. The XZ catalog constructed by Van Fiandern at the sition matches, usually slightly over will be available with USNO'S version U. S. Naval Observatory in ]967.3 052 difference in R.A., and are listed (basis) 79A. If "79A" (or higher nm- in Table 2. The coordinate matching ber) is printed for the basis on your I recently formed a Zodiacal subset of was so successful partly because dou- ACLPPP profile, the prediction has the Perth 70 catalog and made a bles involving relatively bright sec- been corrected using the improved XZ computer comparison with the SZ ondaries with separations of a few arc position of the star. However, many catalog, the catalog data being seconds or less were excluded from ACLPPP profiles have been computed provided on magnetic tape by USNO. The Perth 70. with the earlier 75 and 76 USNO ver- stars were matched by coordinates sions (see IMPORTANT INFORMATION (maximum differences gi1owed were 052 Table 2 REGARDING GRAZING OCCULTATIONS in RA. and 3" in Dec.) and positional Zodiacal Stars whose Perth 70 - SAD Posi- AND USNO PREDICTION VERSIONS, on differences computed for the epochs tional Differences at Epoch 1980 Exceed 3:0 page 155). 1975 and 1980. The resulting list should be especially useful for 1980 Pos. References predicting shifts for USNO Di fference grazing occultations (see final Ref. # SAD # SRA # DM Nwnber Sep. P. A. MaA 1. HOg, E. and von der Heide, paragraph). Of the 2848 zodiacal Perth j., "Perth 70, a Catalog of 70 stars, two (SRS 42779 and 11277) of Z12334 139087 11347 -3° 3385 4!'87 88?7 8.6 Positions of 24900 Stars," which are apparently the same star, Z18444 186683 14778 -28 )4476 4.38 277.5 8.4 Abhandlung aus der Hamburger Z19917 162311 15351 -19 5344 3.69 255.0 8.5 Sternwarte, 9 (1976). Z.C.. 1849 = SAD 139022 = B.D. -2"3593, 2. Robertson, J., "Catalog of only'23 were not matched with SZ Z20141 187990 )5428 -28 15685 3.92 275.3 8.8 Z20307 188112 15488 -22 5100 5.26 222.2 6.8 3539 Zodiacal Stars," Astro- stars. For four of these stars, the R.A. was not observed at Perth (three Z22409 163996 16461 -17 6129 4.03 254.4 7.4 nomical Paper3 prepared for otherS'in this category had been Z24357 165326 17676 -n 5933 3.31 276.8 8.4 the use of the ~rican eliminated earlier). The computer Ephemeris and Nautical Alma- logic someho"w failed (actual nac, 10, Part II (1940). The Z.C. coordinate match was rather good) for The epoch 1980 mean diVerences (in is a compilation catalog with mean one star, SRS 10983 = B.D. "0°2942 = the sense, Perth 70 - SZ) for all com- epochs around 1910. SAD 138774 = Z )?893. Eleven stars are puter-matched stars were -0:58 in RA. 3. Van F1andern, T. C., "A Discussion not in the (taCOSO) and 0!'00 in Dec. The mean R. of 1950 - 1968 Occuitations of SAD or SZ, but are in the USNO K- A. difference for FK4 stars is less Stars by the Moon," Ph. D. thesis, catalog. which I compiled from non-SAO than 0':2 in zodiacal declination Yale (1969). stars from the Z.C., Yale, and AGK3 zones (Ref. I, p. 47), so the large catalogs; these are listed in Table }. mean R.A. difference probably repre- .sents the failure of corrections ap- *A similar comparison of AGK3 with the Table i plied to the Yale, Z.C., and G.C. sys- SZ matched"11984 stars with mean dif- Zodiacal non-Sl\0 Perth 70 Stars tems to bring them to the FK4 system ferences of -0:'26 in R.A. and -0:°06 in at epoch 1980.* The mean separation of Dec. at 1980, probably for the same USN0 K# SRS# Z.C., AGK3, or DM # Perth 70 positions from SZ positions reasons noted above for Perth 70 - SZ. was found to be 0:'97 at 1975 and 0!'98 The AGK3, with a southern declination K00049 2960 AGK3 N04°17 = BD "4" 8 at 1980, emphasizing the utility of limit between -2° and -3°, sampled on- K00626 3611 AGK3 N02°117 " BD +2°161 Perth 70 data for setting up observing ly the northern part of the SZ, while K07196 14185 BD -18° 4519 sites for grazes. The 1980 separations Perth 70 concentrated on the southern K07199 ]4255 BD -21" 4626 for many stars, especially those where part. The mean AGK3 - SZ separation K07259 14651 Z.C. 2620 = BD -20° 5003 the SAD source was G.C., exceeded 2". was found to be 0:'92 at 1975 and i:'OO K07312 14862 BD -20" 5147 at 1980. Although the mean AGK3 epoch K07328 14948 BD -18" 5008 Richard Schmidt and others at USNO are is in the early ]960'S, the positions K07348 15018 BD -20° 5240 working with Perth 70 data, as well as (derived from photographic plates) are K07454 15596 Z.C. 2862 = CD -26" 14337 Fk4-corrected data from many other ob- not as good as Perth 70. Graze obser- vdtions have generally shown only . K07513 16789 BD -20° 6212 servational astrometric catalogs i K07521 17264 Z.C., 3257 = BD -18° 6084 available in machine-readable form, to slight improvement when AGK3 shifts derive the best possible positions and were applied to the SZ predictions. The Perth 70 magnitudes are much brighter than the K-catalog magnitudes tation was seen but could not be timed the 19 events timed from a site near accurately. A few observers to the Viilers-La-Faye, France, is from GRAZESDavidREPORTEDId. DunhamTO IOTA north timed the total occuitation. At Jacques Fulgence's report of his vi"su- Fick Observatory, Ames, IA, Beavers al observations. The intensity of the Graze reports should be sent to my recorded the disappeM'ance photoelec- star's light is shown as a function of current address, P.0. Box 488, Silver trically, but the low daytime altitude time, with 0.0 indicating that the Spring, MD 20907, U.S.A. As usual, if made the record so nodsy that on)y the star is completely occulted and 1.0 possible, a copy also should be sent time of the event could be determined. showing it unocculted. He recorded to H. M. Nautical Almanac Office, Roy- A large weather front with heavy rain three partial flashes (A, C. and D), al Greenwich Observatory, Herstmonceux prevented observation by several other one partial blink (B). one complete Castle, Hailsham, E. Sussex BN27 1RP, planned expeditions in North America blink (E), and a gradual disappearance England. There is more information east of Oklahoma. (F). Another expedition, to FertC-St. about reporting data on p. 93 of #10. Aubin, France, composed of 9 observers The table of observed grazes is in the The weather was 49"20nm464 U.T same format used in previous issues. more favorable · AB' 25mn42a U.T in Europe, Intenjity I 4~u~J ^ The first known observations of a where the same graze of Aldebaran (ZC 0692) were made cccultation oc- on 1978 April 1'1. Rick Wright and two curred shortly others attempted to observe the graze after sunset. ""i'jQ"-",-:-:!y& JUl ' ' ; : : ' : : i:: · i ' from Southeastern Oklahoma State Uni- Three sUccess- ' a ' P : ;i6 57f 3 49,5 Z,l 3,3 Zg 4,9 u,z 6,1 \p,3 4,4 5 : jg 4l,l 8 s a,r : versity in Durant, OK. Observation was ful expeditions "~ ~ '"—V——"' are listed in difficult due to low altitude in the A "phase L" Phase 3"Pka'e the table. The daytime sky and glare from nearby 89,1 aecondu 41'5,1 Aecondu 3Z,1 mcondeo white buildings. A half-minute occu1- chart showing 155

(mostly Belgian) led by Schwaenen Jean due to a small cloud which passed in atrociousthe highlywintergibbousseeingwanin?tenperaturemoon and obtained 62 timings. Some of these, front of the moon at the wrong time. made with 2 or 3 telescooes at the was 12° F) prevented any useful obser- same site, seem to be redundant. A Walter Morgan reports that he saw 12 vations. While driving through Freder- number of gradual eyents due to Aldeb- events during the July 2 graze of Al- icksburg after the graze, the automo- aran's angular diameter were scE·n. debaran, making it the best he's seen. bile of one of the Richmnd observers Some unresolved questions, about some The graze occurred shortly after sun- was struck by another fast-moving au- of the positions, remain. The expedi- rise. Apparently over 30 timings were tomobile, knocking the observer uncon- tion will be listed in a future issue obtained by his 7-station expedition scious and breaking one of his ams. when they are answered. WQ}fgang Beis- south of Reno, NY. The graze probably Ker, a member of the Astronomische Ar- also was observed from California. For the graze of ZC 806 On 1978 May beitskreis Hannover, recorded the to- 10, an asterisk precedes the shiEt tal occultation disappearance photoe- Harold Povenmire has finally assembled value, indicating that,it is a mcan.j lectrically with a 22-cm Cassegrain reports of his large expedition for value. The timings made'during the ·- telescope at Hannover University. They 1925).the 1976SeeAugusto.n., 281 60),raze 94of andSpica]09.(ZC graze occurred in two groups, one be- estimate the angu7ar diameter from fore and one after centra1.graze.,,Oa- their record to be 0'.'021 ± 0'.'003. Unfortunately, a cloud covered the Boll notes that for Watts angles"below moon during part of the graze for many ]85°, the shift was O;'JS north, while The ICTA expedition to Billings, MT, observers, causing many lost timings. for ld.A.'s greater than 186°, it,was for the May 9 graze of' Aldebaran was Adding the results of all expeditions, 0!'36 south. Apparently, there is a canceled due to an uncertain weather a total of ]47 timings was obtained, discontinuity in Watts' data there forecast for the area. Paul Asmus had making it the 7th most sucessfu11y ob- caused by his difficulty in defining a planned to drive there from Denver, served graze. spherical datum where the eastern and but was prevented from doing so by an western hemispheres join near the unusual late storm which dumped two Unfortunately, the first known injury poles. Most of the ACLPPP profile feet of stkm on-the city. An expedi- requiring hospitalization resulting points are in accuracy class I. tion near Penticton, B.C. was clouded from an attempt to observe a graze oc- out. An observer from Great Fails, MT , curred on 1978 December 29 at Freder- An B-station Richmond - d.c. joint ex- traveled to the predicted limit, where icksburg, VA. There were 8 stations in pedition led by Emil Volcheck set up he observed one o.ccultation of the star. the joint Richmond - D.C. expedition near Stony Creek, VA, to observe the He m'ksed one of the contacts for the graze of ZC 1381. Glare from graze of ZC 1271 on March 20. About an hour before the graze, clouds moved in Star % # i§' C Ap from the north and west. I decided to m 9l Number,Ma.j sa 2 Location Sta ,Tm, £ £m. Organizer ,S.t. HA. ,b. drive to a site in the limit over 10 miles to the southeast (the small 1976 roads in the area did not go conven- 1 13 Z03748 7.2 87" Toms k, Siberia ,.1 413 A. Morosov iently in that direction) to get away 4 4 0654 6.0 20+ Yeniseisk, Siberia 1'2 11 V. Kharevich from the clouds. Railroad tracks al- 8 23 1886 5.7 14+ 6S Kroonstad,R.S.A. 10 52 9 8 M. O: Overbeek 55173 18 most coincident with the predicted 8 28 1925 1.2 15" 7S Wabasso Bch., FL 33 103 9 6 Harold Povenmire northern limit allowed me to know quickly where I was with respect to 1977 the limit. The clouds overtook me at 3 }2 2050 8.1 43' Coimbra,Portuga1 1 } 3 15 Jose OsOrio my new site, where I e.ssembled my tel- 7 24 2114. 5.8 61+ 3S Parys. S. Africa 2 )3 7 10 Jan Hers 205177-29 escope and equipment only minutes be- )2 15 Z23942 7.9 34+ OIiv.deAzem. ,Port. 1 I 2 15 jose OsOrio fore the graze started. The sky looked 12 18 0053 6. g 60" S Palmerston N.,N.Z. i 7 8 N. Munford discouraging, with only a few sma?1 breaks in the clouds." A few seconds 1978 after central graze, a long break in 1 3 1946 7.2 40- -2N Victoria, TX ] 3725 Don Stockbauer the clouds occurred, sq I was able to 2 )1 C958 7.7 ]5+ 4N Dacono, CO I 04' 20 Paul Asmus S6 4 make 3 timings during"14 minutes be- 2 12 Z01042 8.3 22+ IN San Antonio, FL 4 6625 Thomas Campbell IN 3 16 fore the clouds closed in again. The 2 12 Z01042 8.3 22+ IN Titusville, FL 1 1 , 20 Robert Berry 3 16 observers who stayed in Stony Creek 2 13 0310 7.7 32+ 3N, Freihdt, TX 3 11 7 15 Don Stockbauer 0 5 32 were completely clouded out. ' 2 13 031 0 7. 7 32+ 6N ·Reddick, FL 3 7720 Thomas Campbell 2S 8 32 2 13 0310 7.7 32+ 7N Daytona Beach, FL 1 4 25 Robert Berry IS 8 32 J0229], whose graze was observed on 2 14 0437 7.4 43+ 6N Kyle, TX 3 13 8 15 Don Stockbauer 4S 8 45 1978 May 11, is B.D. +)8° 1123. 2 }7 0814"5.3 70+ IN Calgary, Alberta 4 4 i5 john Howell 2 70 2 22 ?428 3.8 99+ 23N Calgary, Alberta 3 4 ' 8John Howell 358 5) The graze of Z03748 = SAD 94021 at 2 22 1428 3.8 99+ 27N Greenville, MI 3 6 8 '15 Homer DaBoll CO 3 51 Tomsk' on 1976 January 13 had not been 3 4 2789 7.3 23- S Tolaga Bay, N.Z. I 3 20 Glen Rowe predicted, but since Morosov normally 3 11 0247 6.7 9+ '4N 0viedo,Oomin.Rep. 1 4 "20 John Van Allen uses a printing chronograph for timing 3 16 0823 6.6 48" BN San Miguel, P.I. 1 6 8 Oscar dc Ids Alas occultations, he was able to time the 3 20 1271 5.9 80" 9N Joyner, VA 1 36' 25 David Dunham 2S 4 64 four events which occurred during a 3 37 2685 7.0 53- 6S Shady, FL 2 4 6 25 Thomas Campbell 10986-61 half-minute span. 3 31 2685 7.0 53- 6S Hi·ms, FL 1 6 :. 25 .Robert Berry 4 )0 Z02522 7.5 6+ 2N St.Petersturg, FL 8 20 7 25 "Den,8ricker BN )0 48 [Ed: Thomas Campbell, Jr. (5405 98th 4 10 0454 5.8 6+ -1 S Mason, IL 1 4 7 20 Homer DaBoll 2NI89 50 Ave.; Temple Terrace, FL 33617) plans 4 I) 0692 }.1 17+ S V111.LaFaye,France 1 19 21 jacques Fulgence to lead large expeditions 'in Florida, 4 I} 0692 I.] 17+ S Vallorbe, Switz. I 6 9 20 ·'Hans-joachim Bode for the Aldebaran grazes on Sept. 22 4 11 0692 1.1 17+ S Ptjssens, Switz. 1 2 2G Maurice Roud and Nov. 16, and the Venus partial on 4 12 203972 7.1 19+ -4S Gilroy, CA 2 2625 James Van Nuland 0187 68 Dec. 26. For details, send him a long, 4 14 Z06094 8.1 36+ 5H Wallingford, CT 1 C ID Edward Wetherbee 3S self-addressed, stamped envelope.] 4 14 1003 7.2 36+ 6N Pleasonton, KS 3 11 4 15 Robert Sandy 0 8 73 4 14 1091 6.7 44+ N L.Cb.S.juan,Spain 5 10 6 Luiz Quijano IMPORTANT INFORMATION REGARDING 4110615 3.6 45+ -7S Lake City, FL 1 5 15 Harold Povenmire GRAZING OCCULTATIONS AND '" 4 15 Z07277 9.1 45+ 6N Fredericksburg,VA I 1 2 25 David Dunham C 7 72 USNO PREDICTION VERSIONS 4 16 Z08230 9.3 55+ 7N Potomac, MD 2 2220 David Dunham C 6 67 5 10 0806 5.} 8+ 2S Petersburg, IA I 67 20 Frank Olsen 188 71 David W. Dunham 5 10 0806 5.1 8+ 2S Oswego, IL 5 13 7 13 Homer DaBo11 *25188 71 5 11 J02291 9.2 )3+ IN Silver Spring, MD 1 1 2 25 David Dunham CO 7 72 Severa7 important changes (ho.pCfully, 5 13 128] 6.4 37+ OS Lugano,Switzer1d. i 4 15 Aige Edi improvements) have been made at USNO 6 12 1478 7.2 32" -OS Holland, TX ) 3515 Don Stockbauer in recent months by Van Flandern, 6 13 Zlii55 8.3 50" S.O.Avelines,Be1g. i 6 20 jean Bourgeois Richard Schmidt, and othCrs. Until two 6 14 )692 6.8 52+ IN Jefferson, AR I I 8 20 Homer DaBo]1 C 0 16 months ago, graze data were being com- 6 24 3]55 6.8 83- 6S Simnerville, TX I i 7 25 Don Stockbauer puted with USNO'S version 768, which 156 is similar to other USNO versions used tia11y a combination of the SZ catalog small. I do plan to re-reduce some during the last few years. Version 78A (used in all previous versions) and my past graze observations using 79A to was created in May. It included a re- K catalog (see o.n.. 1 (13), 138), but see how good it is for graze predic- vision to many of the SZ star posi- with more accurate star positions and tions. It may be necessary, as a re- tions north of declination -4°. About proper motions used (as in version sult, to change some of the empirical 40 observational catalogs in machine- 78A), and Perth 70 data are now in- corrections which we've built into the readable form were reduced to the FK4 cluded. Hence, the version 79A XZ cat- ACLPP Program. Unfortunately, time system and least-squares solutions alog should have the best possible will not permit the comprehensive made to obtain positions and proper star positions. The USNO reference analysis that should be done. We will motkins for the stars, which should be numbers will be preceded by X, except be interested in how well version 79A a big impr'ovemerit over the SAD and for ZC stars, where (as with the cur- performs during upcoming grazes; some Z.C. data for the stars involved. Data rent Z) the prefix is blank. An SMBDN of the changes in star positions are from the accurate Perth 70 catalog for tape soon will be available for 79A; substantial. I hope the transition to nainly southern stars (see COMPARISON it will include empirical corrections 79A won't cause too many problems. OF.ZODIACAL SUBSETS GF THE PERTH 70 based upon the first analysis of all Since the 79A star positions should be A!1D SAD CATALOGS, p. 153) were not in- available occultation observations the best available, it should no long- cluded. Due to the improved accuracy made from 1627 to 1977. Overall, the er be of any use to request shift cal- expected for the northern stars, I 79A system should be a vast improve- culations using the Yale, AGK3, or computed some of the profile data for ment. A disk file correspondence be- Perth 70 catalogs. If your profiles the current quarter's grazes on ver- tween the SZ and XZ catalogs has been used version 78A, I will compute a sion 78A. Unfortunately, at the time, established at USNO for rapid automat- Perth 70 shift using the same proce- there was no lunar ephemeris tape ic conversion of Z to X numbers. Both dures employed eaFlier for AGK3 ("SMBDN" tape, which includes empiri- total and graze predictions for 1'979 shifts: Three or more observers should cal corrections to be applied to the will use X numbers rather than Z num- be planning to observe the graze; the ephemeris positions based upon analy- bers for non-ZC stars. These changes date, star's USNO reference number, sis of occultation observations) com- cause some problems for grazes. Al- star's position source as given in the patible with 78A, so the 76B version though the basic graze data through limit prediction, and P.A. of graze SMBDN tape was used. The significance the end of 1979 already have been com- should be specified; and a self-ad- of the errors caused in doing this, puted with version 76B, even for graz- dressed, stamped envelope or card especially relative to the improved es occurring now, the predictions can should be enclosed. Requests should be 78A star data, is currently unknown. be corrected to version 79A by comput- received by me preferably two or more An SXBDN tape for 78A has been gener- ing the profile data with version 79A. weeks before the event. The 78A star ated. The lunar ephemeris used for Watch the version, which is printed on positions should be better than either this tape was fitted to lunar laser the ACLPPP profiles. Overall, 79A Yale or AGK3, so shifts computed using ranging observations, which should should result in a big improvement in those catalogs should not improve the make it rather accurate, but I feel graze prediction accuracy..But shifts prediction. If your profiles used e"i- there could be some errors in declina- observed during past grazes reported ther 76B or earlier versions, Yale, tion, since there has been no deter- in this, and pret'ious, issues of o.n. AGK3, and Perth 70 shifts can be re- mination of empirical corrections relate to version 76B, which uses com- quested, as before, since those cata- based upon an analysis of occultation pletely different (less accurate) lu- logs shoiuld have better positions than data yet. The empirical corrections nar ephemerides and corrections, and the Z.C. or G.C. In versions 78A and in declination for earlier versions star positions, from those of 79A. So 79A, the position source information have amounted to several tenths of an the reported shifts are meaningless in the predictions still will say arc second, quite significant for for version 79A. On future graze re- "Z.C.", "Yale", or "G.C.", for exam- grazes. In early July, version 79A be- ports, you should specify the version ple, when Perth 70 or a combination of came operational. Rather than using given cn the ACLPPP profile when re- other catalog data actually were used the SZ star catalog, it uses an ex- porting observed shifts. Hopefully, for the position and of panded "XZ" catalog, which is essen- observed shifts using 79A will be the star.

OBSERVATIONS OF THE tude. Thh was confirmed by Rick Bin- A detailed regional map of the occul- OCCULTATION BY PALLAS ze1 at Macalester College, MN. The tation, like those for upcoming events visual magnitude drop in case of an in this issue (see PREDICTIONS OF QC- David Id. Dunham occultation would be only 0.2, too CULTATIONS BY MINOR PLANETS on page small to notice visually; the drop in 157) was prepared and included in The occultation of SAD 85009 by Pa11as B would be 0.4, slightly better. Un- Special Bulletin #4. It is reproduced on May 29 was recorded photoelectric- fortunately, it was then too late to here, with the shaded area showing the ally from seven observatories, making warn visual observers, either in o.n. approximate actual occultation path. A it the most accurately observed occul- or Sky and Telescope, SO that a number series of astrometric plates was taken tation' by any airless object, includ- of spurious visual observations were at Lowell and U. S. Naval Observator- ing the moon, to date. Although Gordon received. Taylor's and IOTA'S bulle- ies in Flagstaff, AZ. A few weeks be- Taylor issued I.A.U. Planetary Occul- tins were sent only to known photoe- fore the event, indications were that tation Working Group Bulletin #9 and I lectric observers, due to the star's the center of the occultation shadow distributed IOTA Special Bulletin #4 faintness and to save mailing costs. would shift 0:3 south, as noted in"

about this event, most of the astrom- Occultuion of SLO 85009 by Pallm, 1978 M&y 29 etry was done at, and most observa- 0."¶ M Q" tions coordinated by Larry Wasserman ¶Ei \ I i -C KV _. . -\. - , ' / " '~ at Lowell Observatory in Flagstaff, O:'Z N " " AZ. Interest in the event was high due ' \, * t ' o'j N to the wide path (so that careful as- i I , 0 \ "\ rl trometry could ensure successful ob- Q-j' Al , . ,L _ "" """"" ' e servation by the Kuiper Airborne Ob- 0"2 5 m * , 7,// " " ""_ + . _ + servatory) and the fact that it was - ',, , / , " - E=- ,- ..... sure to cross the United States and/or Q.'f. 5 ' ' . '' .r_-^ , 1///'' '" """. .^ "" _"1':"n""'""T"'"h " Y/m,: ,,' "' ' / . / 0:2N southern Canada from coast to coast. . /"' " u _._. ! ¶$..-E ' -. -.A . . /1'.,,-±, , ' ,, There is only one previous photoelec- 0.60· S p., _e_ N .._ . ,, ,,, , , !'±4-.""' -= , ' ' · . , /, O tric asteroidal occultation observa- 0,8 S —--A" " " " 1 ' "" " " " " """ ""--- '"/ qQS tion, also involving Pallas and made . -.-...-. at Naini Ta1 Observatory, India, on -" "P—- - — ---- -. . " """""-· ·'.1 ' ," { )961 October 2; only the one chord was j;os-° mb -- - +-- --T ,. .., . . IIQbs observed. '" " 4-- |.2 s i 15 '2(" L',?5" "" " qZ s In late March, Bob Millis, Flagstaff, 54 27" , , . sent me a card reporting that SAD 5'-?'" T 3" _ t , I u' S ' 85009'S photoelectric V magnitude was "~ is , , 5 4^ I ,/ . " ) 10.8, much fainter than the SAD magni- -im" ,> 5'2,- ""g -55"

J 157

Bulletin #4. During the week preceding the paper through, and restarted it. White (Lowell) observed with the new the event, up tO two days before, the Seconds later, the pen abruptly swung 92-inch infrared telescope-at Jelm Flagstaff indicated that to the left when the star reappeared. Mountain, Wyoming, where the'occulta- the shift would be 0:'6 south. There Then came the 5h25m time announcemerit, tion lasted only about 20 seconds. In- were five mobile photoelectric observ- and Mike again pressed the second pen diana University's Goethe-link and ers, each of whom wanted to be at the button. The occultation lasted 38Q Morgan-Monroe observat(jriescrecorded center. But four of the successful seconds; the second photoelectric rec- 26S and 23S occultations, respective- fixed observatories were already near ord of an asteroidal occultation had ly, due to their appnoximately 20-km 0:'6 south. It might have been better been made. Wayne Warren just remarked, north-south separation and southern if the mobile stations were dispersed "That's not the way it usually happens location in the path. Harold Reitsema, more to augment the fixed observatory in astronomy." About ten minutes lat- Lunar and Planetary Lab., Tucson, AZ, coverage which, however, was uncertain er, Richard Radick telephoned from the successfully observed,in two colors due to weather and unforeseen equip- University of Illinois' Prairie Ob- with a portable 14-inch Ceiestron - ment problems at some of the observa- servatory, saying that he a7so had re- which he had used in Mauritius in tories. The KAO and a group from Cor- corded the occultation. March, 1977, for the occultation by nell University which planned to ob- Uranus' rings. He observed near Beh- serve from West Virginia did shift The asterisks on the map show the lo- ien, NB, site of the University of Ne- north somewhat, based on plates taken cations of photoelectric observers braska's 40-inch, which could not be at Flagstaff the night before the known to have attempted the occulta- used as the mirror was being alumin- event, which indicated a 0:'4 south tion. Uncircled asterisks indicate ob- ized. It was mostly"c1o'udy, but '. shift. Taylor had obtaimd p:etes with servers who were either clouded out or cleared in the right direction only k the AstrograpNc Catalog telescope at could mt observe due to equipment minute before the occultation! the Royal Greenwich Observatory three problems. Observers at locations indi- nights before the event, and sent an cated by the circled symbols were suc- LUNAR OCCULTATIONS OF PLANETS updated prediction by TELEX to Goddard cessful, recording the occu1tation or Space Flight Center (GSFC); this indi- not, depending on whether they were in ""' °'""'"" :":= is;"' "" "' '°",g=m=7k cated 0':55 south. The time correction the tjccuitation path or not. Some "' " - ,, E:· g:->,,>""" " Y, " q 1~,°g * derived from the astrometry was 1.7 questionable observations have not yet minutes later than the times shown on been resolved. The location of' the KAO my map, which turned out to be close is indicated very roughly by the plane ':'dj ->, > ': ,: 7;2 to the truth. The actual shift was symbol in Wyoming; it apparently was about om south. the only observatory north of the cen- ter of the path, and only a short dis- )i,:!:":,:5 ,, C;t")' Mike A'Hearn from the Universit.y of tance north. The latest results from ---F . · . E £ VENUS \ . \ Maryland and Rick Skillman set up to infrared radiometry and°po1arimetry ., ,C_=g ,. .,*·: ilj-,,o· , ,_m -,_ ,m_ :"yk. observe the event with the 36-inch re- indirectly give a radius for Pallas flector at GSFC'S Optical Facility slightly under 600 km, while the val- near Beltsville, MD. Mayne Warren and ues given in recent issues of o.n. (, j: · hO" ' - -0' -i ' Q" -L '0" C.-l ,9>" "I SO' \-CT i m' , "' ''I)^? I joined them about an hour before the have been a little larger than 600 km. ) t= : )" jj i,] :%:': . h¶ ', '). _) event after having 3pent much of the Larry Xasserman's preliminary analysis weekend d?ing some computaticm and gives 540 km, about 10% smaller than i relaying information about the event. the radius from the modern indirect Murphy's Law was bmken several times observations, which were thought to that night. Clouds were forecast all have an error of only 5%. The occulta- i weekend, due to a low stalled off th2 tion diameters for Hebe and Herculina 3 / ' 1973 VI I 8 f e " H "\ \ )' ±1 Carolina coast. But Sunday afternoon, agreed much better with the indirect k £ MARS i the clouds started to break up, and measurements, perhaps due to the fact , ~ " '" ,,,T k,- .m" ·1 I)" ., _0· C" LI SQ' C-?/' ,W I®-.. ' k' the evening was mostly clear. But when that the latter are S-type objects, r' .I drove to the Optical Facility, the i' whi)e Pallas has unusual spectral 3 sky became overcast as low clouds rol- characteristics with some C-type fea- The maps showing the regions of visi- A led in f""om Chesapeake Bay. Twenty Sr·r tures. Ct dctes Pa17as have a substan- bility of lunar occultations. of plan- ¥ minutes before the event, first-magni- tial satellite (the one claimed by van ets are reprinted by permission from C3 **> tude stars appeared now and then. A den Bos? See FURTHER SUPPORT FOR MINOR the Japanese Ephemeris for 1978, pub- t « little later, 3rd and 4th-mag. stars PLANET MULTIPLICITY, p. 152) which lished by the Hydrographic Department 3. appeared, then the Milky Way; a large passed f.ir to the north or south on of Japan. Region I, orUy R visible; .Qi clear area had formed, with clouds all May 29? The preliminary solution re- Region 3, only D visible. S around. Surely they would close in siduals fem the KAO are much larger H again before the event, but they did- than for the other stations, consider- PREDICTIONS OF OCCULTATIONS Y 2¢ n't until about five minutes after- ably larger than can be explained by OF STARS BY MINOR PLANETS wards. Subsequently, we didn't see any positional uncertainties in the iner- stars the rest of the night. Before tial navigation system. However, I David Id. Dunham turning the photometer on, we could suspect that high-speed photoelectric see Pailas approaching the faint star; timing accuracies multiplied by the Predictions of occultations of stars I was afraid that an occu)tation might asteroid's transverse velocity may be by minor planets during 1978.have been be rather indistinct. Mike switched on smaller than inertial navigation er- tabulated and discussed in o.n., I the photometer and chart recorder. rors. These errors probably can be (13), 134 and (14), 742. Finder charts Just after 5h23m U.T. (the uncorrected virtually eliminated when the Global and maps for some of the upcoMng predicted occu)tation time), Mike no- ' Positioning System (an artificial sat- events are published here; some for ticed that the paper was going in the ellite navigation system which can be events later in the year will appear top, but not feeding out the bottom of used by ships and airplanes) becomes in the next issue. Mitsura Soma, To- the chart recorder. He stopped the ma- fully operational. Unfortunately, SAD kyo, Japan, has recently produced chine, pulled the paper (smeared with 85009'S angular diameter is expected world maps by computer, similar to the much ink) through, and restarted it. to be very small, subtending only maps he has drawn by hand which have 5h24m U.T. was announced and Mike about 13 meters at Pa11as' distance, bEen published in previous issues. pressed a button in synch with WWV to so that its size could not noticeably This time, they have been re-traced by put time marks on the record with th? modify the occultation diffraction joseph Zoda, for publication here. 'The second pen. Nine seconds later, the pattern; it was one of the few stars three closely spaced parc.11el lineS. pen swung quickly to the right, by occulted by minor planets this year show the predicted central occultation considerably more than the width of for which the angular diameter cou7d line, and the northern and southerR the noise, when Pallas occulted the not be determined from a good photoe- limits, with U.T. marked at one-minute star. Then the paper stopped coming lectric occu)tation record. intervals and written at five-minute out the bottom again; I thought, "Let intervals. The two parallel dashed ' it go; it could reappear at any time." Others who successfully recorded the lines show the central occultation But Mike almost instinctively stopped occultation and who have not been not- path in case the minor planet passes the recorder, opened the door, pulled ed above are mentioned below. Nat i:'O north or south (measured' perpen-

V

. 'X. P. 4 r· »' i

8 i 158

P £ P " , : i ' ?. dicularly to . o 0 ' i cover a large enough area to include its path in the +15 Dt . . , " · u , , at least one star shown in the sky i sky) of. its " . '. T t '' o ° "· · '" o ° maps published in Sky and Telescope. predic;ted. path . ", "O'. ' ,, oi" " 'I o · ·° ° , · "g O O 2? with respect to L, . , 9 , O , " 7%m""" " III I i11··

the ,s ta r; ·Com- C ·"rl4 O- .q' , o .. 9 ' ° bined,ephemeris O o ·, " ° © ° cC 1 and stiae ·posi- . , o , g ""~ t)on errors can - .. O D O 0 °° I O ,7,->"7 "6'y- " cause ,path +13 - · O D Q D O { ? shifts, greater . " · , 4 'bel e °, q306: , ,, ° °° i than I", as, the O """—o O , ! ) ,Jify- ? occultation by o O " * O O O Hercubna on ° 8 ° C) 8 ,Q , C)31 O O SAD 93CL64 1l\l Y Me. 1978 A| CI L_ ! Q e Jun.e,, ·7vdemon- , +12 -O ,O m d 3 2 o O " Q70 O 0 O " t

strd-tCd., The O D 0 ° " ° 0 ° e Q D SifjRF7 SC ·a.nd/or . o , ° £ g 'C"""""") '

sunset temina- . O " o tor .is sho'm, +11 . 8 ° .ARIES · "· ,yO · /' ^—'"" Q O rt ,t Zb" w1 th ha tches . " , O Mo , ,' ______/ _ indicating the' ". % , ° , o95 "Tl ° , , , side of night- , · " _ ° _ q b ' " ° ° " , ,.., _ _ O , O time vIs.1b]11t.y- ·L0 - O ' · Oµ¶i O ° " D 0 ' 0 O ' " '" : ' · " . O O Q Q D , /1 The.anore de- . O CBTUS D · Q " O° · OO SAD 140552 by Herculina, 1978 Aug 22 tailed regi,onaj 0 maps .were pre- , ., q ' ° O O ° ° d , O POSSIBLE OCCULTATION BY (2060) CHIRON pared wi th' a "9° ' . k ° t bn " a i , , , , , compu ter pro So" 48 45 ' 44 42 ' 40 ' 38 36 3+ 32 30 28 Z 25" David Id. Dunham gram written by Fred Espenak, Bcwiie, MD, using path terisks show the locations of observa- A possible occuitation of the 10.7- data -on..magnetic tape generated by .me tories from which photoelectric occul- mag. star AGK3 "13°203 by Chiron (= at USNQw The parallel curves represent tation observations have been attempt- 1977 UB, now officially numbered 2060) the path of the center of the ,'occu1 ta- ed in the past, as far as Iknow. The on July 24 was noted in o.n., I (13), tion shadow, considering several di f- regional maps are "falsC" projections, 136-7. J. Derra1 Mulho1)and, Universi- ferent sh'ifts of the minor planet from plotted with a constant linear scale ty of Texas, measured the star's posi- its predicted path with respect to the (constant degrees per centimeter) in tion from a 1952 Palomar Sky Survey stam The nominal path is Iabejed"0". both longitude and latitude, so that plate. The Palomar plate position w.as The parallel curves show the central the observer could, for example, plot in good agreement with the AGK3 posi- path for multiples of O:'i shifts-of updated' computed path points which tion computed for that epoch. Mu)ho1- the asteroid from its predicted path might be computed by Gordon Tay)or. land planned to take a plate with Mc- in the sky, measured perpendicularly Note that the width of the occu7tation Dona7d Observatory's 82-inch telescope to the path. Curves are labeled in the 'path can be estimated on the map from in late June, but the star's elonga- map margins at 0:'2 intervals, "N" or the expected angular diameter. tion from the sun was small and the" -"S" showing shift direction. Dashed ' ' telescope could not point that low in eurjies show predicted U.T. of central Since these are regional maps, differ- the east. An attempt was going to be occul tation. Low star altitude or"twi- ent ones will be published in the dif- made at Flagstaff in early July ttj ob- light boundaries are drawn when appro- ferCnt editions of o.n. Some regional tain a current astrometric position ,of priate. The expected diameter of the maps'," for areas such as Australia or the star, but unfortunately, Chiron minor planet, in km and in arc sec- Japan, will be sent extra to the rela- will be'too difficult to photograph. 9nds, is given in the caption. The tively few subscribers there, rather The available data indicate that the nominal paths were computed using SAP than using space in o.n. occultation will miss the earth's sur- data for, the stars and accurate astrO- face, but if the Flagstaff observa- metric ephemerides which I computed When time and space permit, we will tions give any hope that this is not using precise osculating orbital ele- try to publish finder charts at two the case, a special bulletin will be ! merits supplied by the minor planet scales, a detailed chart and a large- sent to observers in the possible re- 3 centers in Cincinnati and Leningrad; area chart showing the area covered by gion of visibility. some exceptions to obtain improved the detailed chart with respect to fa- predictions, when better data have miliar . Often we can FROM THE PUBLISHER been available from other sources, publish only the detailed chart, in have been noted when appropriate. As- which case, we will try to make it IOTA membership generally inc7udes V predictions for grazes within speci- OccultatioQ or S&0 93064 by (65) Cybele, 1978 Augmt I C fied travel radii, as wei) as Occulta- r Diameter JO9 kin = O!'i2 tion Newsletter and other benefits. A % " '- - ;. ' ,_ '"' 'ry,, :ma1) expiration notice is mailed with "r' '. " , ' ".* - ~6"4 che final issue of a subscription; j ' .7 i 0",5 S ,>" \ )sUally (although perhaps not this * '%r - A ^ time) there is time for you to send,in .H your payment and receive succeeding , ,, d:c S. G' 5(" ,, " j ' issues without interruption, but if jr"" " -.f F- *

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g 1.59

IOTA membership, subscription dectrically at McOonald Observatory ently omitted from previous lists. included, is $7/year for residents of on 1978 March 15, yielding a separa- The possible duplicity of SAD 95795 " North America (including Mexico) and tion of CL'396 as projected onto P.A. Z.C. 1003 was not confirmed by othCrs S9/year for others, to cover costs of )02?0. This is in good agreement with the 0:'457 separation in P.A. 75?1 com- watching the same occultation, includ- overseas ing Paul Maley at Houston (where th'e air mail. European (excluding Spain puted from St. Wierzbinski's orbit, event was more central, and therefore and Portugal) and U.K. observers according to David Evans. Magnitude differences were found to be 1.61 ± less favorable for noticing quick ' should join iota/es, sending DM 10.-- fades) and Robert Sandy, observing the to Hans J. Bode, Bartold-knaust Str. 0.06 in blue and 1.16 ± 0.09 in red; graze near the northern limit (he 6, 3000 Hannover 9], German Federal the w from visual observers is 1.0. Republic. Spanish, Portuguese, and The combined V = 6.88 and B - V = notes that observing conditions were Latin American occultation observers 0.56. During 1978, the star will be probably not good enough to notice ' ' may have free membership in IOTA/LAS, occulted again at McOonald on July 29 phenomena due to close duplicity of including Occultation Newsletter en and December 13. Of course, it will be the star). Espaiiol; contact Sr. Francisco Diego occulted for others during other Hya- Q., Ixpantenco 26-bis, Real dc Ids des passages on the dates given in my Based upon a photoelectric' observation Reyes, Coyoacan, Mexico, D.F., Mexico. article in the january issue of Sky made at McOonal.d Observatory on 1977 . and Telescope; check your predictions Sept. 8, the magnitudes of the compon- Please address all subscription, back for events at your location. Other ents of SAD 96634 = ADS 5885 in.the. Stockbauer list were changed to 9.3" issue and IOTA membership requests to photoelectric observers are urged to and 10.5. A better McOonald observa" Berton Stevens, Jr., 4032 N. Ashland try these occu)tations, since combin- ing results will permit determination tion was obtained on 1978'Feb. 19. The Ave., Chicago, IL 60613, U.S.A. Make results, both positional and magni- checks and money orders payable to of the true separation and position angle. More importantly, Evans stres- tudes, were in much better agreement International Occultation Timing with the Lick I.D.S. values, indicat- Association, or to IOTA. ses, observations made with Johnson U, B, V, and perhaps Stromgren filters ing that the 1977 duplicity informa-f tion may have been spurious. 'Conse- NEW DOUBLE STARS will permit colors of the individual stars to be obtained and their spec- quently, the Stockbauer"1ist'magni- ·· tral types estimated. These stars can tudes should be changed back to their David Id. Dunham then be more accurately compared with original values of 9.2 and 11.2. · ' [Ed: This paragraph consists of the mass- relation. Similar arguments apply to SAD 93926 = ADS On 1978 April 15, I 0b"sCrved' an'occuV- extracts from a postponed portion of 3210; the third Hyades star with visu- tation of SA0'96746' = A Geminorum = D.\LD.'S article for #13.] The Z.C.- 1106'"= ADS 5961 under good condi- spectroscopic binaries..from Wilson's ally determined orbital elements, ADS 3475, can not be occulted by the moon. tionZ"l"was·ab1e'to tiijie the disap- catalog..were crossreferenced with pearandC of the visual secondary, ' ' codesUSNO'Swill appear in..predictions for 1979. Ail known data are now on hand SAD 98709 = o Leonis = L,C. }428.= ADS whose magnitude I estimate as 9.5. If SZ"cata1og last July..Double star it had beetg as faf·nt as the YO.7 given for the double star list. Paul Coteau. 7480, mag. 3.5, is a close, double- .is concerned that his information has lined spectroscopic binary with'a per- in the Ltck I.D.S., I"wou1d not have not been published..The list, as it iod of 14.5 days. An occultation of' been able to see;-it near the'moon witih stdiids, [is in the hands of] graze this star was recorded photoelectric- njy 25-an reflector. ThC.disappearance ' computors. I hope we can publish the ally at McOonald Observatory on 1978 of the'Primary aptjeared sharp, in ... eiitire list for all IOTA members Feb. 22, but no evidence for duplicity agreCm'ent with a photoelectrfc record [soon]. Before this is done, I need to was noted, apparently due.to poor geo- of the same event obtained'by'Rick find time to [perform various tasks].. metry. Evans calculates that the maxi- Skillman with a 30-cm rCflectowat:the Progress with the double stars is, and mm possible separation should be Goddard Optical Facility neatby. There ," prObably will continue to be, 0':008, so that it shou?d be resolvable appears to be no close companion like excruciatingly slow. at times with photoelectric occulta- the possible star noted in O.n. #11. During nearly three tion observations. Data collected at ,. . . , t wC'eks in July and August, Rick Binze1 two or more observatories during tm The quick-fade during the disappear-' came to..help me with various projects occultations at appropriate pha'ses'of ance of SAD 976)8 on 1978 April 16 was ..resolved discrepancies..to make the the star's period could determine the also noticed by joan Dunham and Wayne completion of the..double star project masses of the stars. 'Narren, who were also in Potomac, ED, at least possible in principle. The where we had attempted to observe the Hyades issue of o.N...would have been SAD 93022 = 3] Arietis = Z.C.. 384 w,as graze of another star. greatly delayed without his help. discovered to be a-close double at Mc- Donald Observatory on 1977 Sept. '30, An occultation of SAD 98146 was ob- The table lists additions and as noted in o.n., i, 140 (#13). Evans served at McOonald Observatory on 1977 correc-"tions to the special double and Fekel note that the period is March 3. There is some ir.dication of star list of 1974 May 9 not listed in likely between 4 and 9k years, and duplicity, but the data are too noisy previous issues. The colunns and that at certain epochs, double lines for an analysis. Nathaniel White, general format are the same as in might be visible in a high-dispersion F)agstaff, AZ, claimed it as a possi- previous issues. spectrogram. Feke1 made such observa- ble double in ]975, as tabulated in tions on 1977 Nov. 3, when no line O.N., 1(5), 45. The close duplicity of the A- doubling was found. Since the true component of SAD 94554 = 1)5 Tauri = separation could be as large a 0:'2, Both the D and the R of SAD 98267 = a Z.C. 814, discovered by Robert Hays visual and speckle interferometry ob- Cancri = Z.C. 1341 = ADS 7115 were re- on 1978 February 17, was indicated in servations are recommended. corded photoelectrically at McOonald the table of the last issue of o.n. An Observatory on )977 Sept. 10. The oc- independent discovery of the duplicity The interesting Hyades eclipsing bin- cultation was nearly grazing, with a was made at McOonald Observatory, TX, ary V471 Tauri = B.D. +16° 516 = duration of only ten minutes, with when David Evans photoelectrically J00004 was described in o.n., i, 139 disappearance of the 4.3-mag. star a recorded the same occultation. the (#13). More accurate data about the short distance on the bright side of photoelectric data give a separation Nelsonsystem arein Ap.givenj., by173,A. 653Youn[1972and MayB. the thin crescent waning moon. The of 0:099 in PA. 98?), with Am = 1.13 good-quality traces show no evidence ± 0.06 in I); the mean separation of the nearly of the close duplicity claimed in o.n. " blue, and 0.90 in red. This is in good circular relative orbit is 2.21 x jQ6 1, 14 (#2). agreement with Hays' visual estimates km, and the distance is 60 to 70 par- at P.A. 63°, indicating that the true secs. The maximum angular separation A graze of SAD 97843 = 29 Cancri = will then be only O:'OOO2, too small to separation and position angle of the Z.C. 1271 was observed the same night be detected during lunar occultations. close pair probably is close to the that Sandy noticed a possible dinning McOonald Observatory results. during the total occultation at his SAD 94002 = Z.C. 684 = ADS 3297, a location, but observing conditions and SAD 93870 = 55 Tauri = Z.C. 636 = ADS visual double in the Hyades, is given the geometry during the graze were not 3135 is one of three visual binaries in the table, since it was inadvert- favorable enough to detect duplicity; in the Hyades for which orbital elements have been determfned. An occultation of the star was recorded r V ".

photo J" 160 see p. 155 about the graze. Using a Several new non-SACi (and non-AGK3) lists several binary stars, including 20-cm telescope, I didn't notice any double stars also are listed in Circu- some occultation binaries, which he evidence of duplicity during an occu1- lar o4O. 75 and are givert in our list. could not resolve by $?eckle interfer- tation on ]978 June 10, but due to J00399 is in the Hyades region at 1950 ometry. One of these is SAD 93062 = poor seeing at the )qw ajtitude, a r.a. 4h3m, Decl. "15°25'; it is A.C. Z.C. 399 = µ Arietis, which he 7ists slight drop before disappeorance +15°4h36" No. 27. The ¶950 coordinates as having been discovered by speckle could have been missed. Bob Panek re- for thk star listed "anonymus" are interferometry by Blazit et al in corded the same occultaticm with high- R.A. 9 4437, Dec1. +14°03'. 1975. Actually, it was discovered with speed photoelectric equipment at Penn- a photoelectric occultation observa- sylvania State University. There was The data for SAD 97442 are improved tion by dc Vegt at Hamburg Observatory no evidence for close duplicity, but a values by Nolthenius, as given. The * in 1969. Blazit et al give a separa- component with a separation as great indicates that duplicity for the star tion of 0!'028 in P.A. 147° at epoch as that claimed by Sandy would likely was previously suspected, in this case 1975.64 and 0!'036 in P.A. 145° for be outside the observed time range. by Sincheskul at Poltwa in 1975 (see 1975.78. According to photoelectric O.N., I (IQ). 109). occultation data, the separation was SAD 139058 was flagged as the compan- 0!'049 in PA. 263° in 1973 jan.-Feb.; ion of another SAD star (double star +17°1315 - K33488 = AGK3 NI7°666. see o.n., 1 (ID), 109 and (n), )20. code E) as the result of a matching J02832 is A.C. "18"6h24m No. 5]1 at Several PIeiades stars were unre- error when the Stockbauer list was 1950 RA. 6h27m3459, Dec1. +17°44'}8". solved, probably because their separa- formed; in fact, the star fs not a tions are less than O:'Oi and hence un- member of any known double star sys- In the latest issue of publ. Astron. resolvable by speckle methods. The tem. Soc. Pacific '(90. p 330, 1978 June-ju- components of SAD 139033 have Am = 3.3 ly), Sarah Lee Lippincott and Michael which might be hard to resolve at 0!'04 Alfredina do Campo, Observatorio dc lkjrth, Sproul Observatory, announce expected separation. The unresolved Lisboa, Portugal, said that the 1977 that SAD 77705 = Xl Orionis is an as- stars are listed in the table below. occultations of SAD 160)80 (= Z.C. trometric binary with a period of 2436) and SAD 161848 (= Z.C. 2731) 14.25 years. "A" has been used for the Stars Unresolved by McAlister, 1975-6 which he observed were gradual; the method code to denote an unseen com- stars are known close visual doubles. panion whose presence is detected by SAD ZC Other Names periodic variations in proper motion In the table of new double stars in as determined from careful astrometric 76126 0536 ]6 Tauri = Celaeno the last issue, the SAD number 93072 analysis. Xl Orionis is a star very 76131 0537 17 Tauri = Electra is incorrect; it should be 93070. similar to the sun, about 70 76155 0541 20 Tauri = Maia away, according to the Sproul study. 76199 0525 n Tauri = Alcyone The I.A.U. Double Star Comission's The next maximum separation, expected 76228 0560 27 Tauri = Atlas Information Circular No. 75 (1978 to be about 0!'6, will occur in 1982, 76425 0598 36 Tauri June) gives new orbital elements for soon after which a series of lunar oc- 76532 0628 uj Tauri SAD 75671 = Z.C. 438 = ADS 2253 by cultations of thc star wi17 begin. The 78135 0946 n Geminorwn A Costa-Morales and for SAD ]63771 = companion is expected to have about 93932 0661 77 Tauri Z.C. 3015 = ADS 14099 by Heintz. These one sixth the mass of the primary; 9405) 0702 al Tauri are presumably an improvement over the hopefully, it can be resolved and the 719164 ]734 x Virginis previously available elements publish- magnitude determined from a future qc- 139033 ]853 di Virginis ed for these binaries in Finsen and cuttation. If there are any previous Morley's catalog. At epoch 1979.0, the photoelectric occultation observations A. Kirichenko, Uzhgorod, USSR, noted separations and position angles will of this star, the secondary my be ev- that the reappearance of the 4.7-mag. be 0':48 and 255?3 for Z.C. 438 and ident in them, or a lower limit for MO star SAD 94628 = ZC 0832 on 1976 ono and 1'13?0 for Z.C. 3015. These the magnitude of the secondary might Oct. 13 was gradual. Diffraction en- are rather different from the values be established. hanced by the star's relatively large computed with the previous elements. angular diameter probably caused this, Neither of the two stars is currently In an article on p. 288 of the same rather than duplicity. being occulted. issue of p.a.s.p., Harold McAlister

NEV DOUBLE STARS, 1978 JULY 75 . SAD ZC M N MGI MAG2 SEP PA MAG3 SEP3 PA3 DATE, DISCOVERER, NOTES

77705 0894 A V 4.4 0!'6 1978, S. Lippincott and M. Worth, Swarthmore, PA 93484 P K 7.0 10.5 .035 13° 1977 Feb 25, D. Evans, McOonald Observatory, TX 93933 TK g.; 8.70.02 23 1978 Mar 15, R. Nolthenius, San Diego, CA 94002 0684 V M 6.9 7.0 3.1 277 Known visual double (ADS 3297) 94358 P K 1978 Mar ]6, D. Evans, McOonald Observatory, TX 95748 .TV 7.9 9.00.25 62 1978 Apr ]4, P. Ma)ey, Houston, TX 95759 TK 8.2 8.70.05222 1978 Apr 14, P. Maley, Houston, TX 95775 TK 9.8 9.Ei 0.1 96 1978 Apr 14, P. McBride, Green Forest, AR 95795 1003 T K 8.0 8.0 0.05 32 1978 Apr 14, P. McBride, Green Forest, AR 95866 P K 8.5 10.3 .019 61 1978 jan 22, Morgan, McOonald Observatory, TX 97356 TK 8.6 9.1 0.3270 1978 May 13, P. McBride, Green Forest, AR 97395 TK 9.5 9.5 0.1 90 1978 May 13, P. McBride. Green Forest, AR 97442 TX 8.8 9.00.05}24 * 1978 Feb 20, R. Nolthenius, San Diego, CA 1978 976]8 TK 8.4 8.40.03156 Apr 16, D. Dunham, Potomac, MD 97827 TK 9.1 9.6 0.3 9C 1978 Jun 10, P. McBride, Green Forest, AR 97843 )27) T K 6.4 6.9 0.25 224 ]978 Mar 20, R. Sandy, Kansas City, MO 98661 TK 9.0 9.5 0.4158 1978 Play )5, J. Van Nuland, San Jose, CA 109560 0131 T K 9.0 9.0 0.1 270 1976 Jun 21, A. Zhitetski, Kiev, Ukraine 109790 P K 9.3 9.9 .060 272 1977 Nov 22, B. Smith, McOonald Observatory, TX 139302 TK 9.4 9.4 0.) 90 1978 jun }6, P. McBride, Green Forest, AR +17°13]5 T K 10.3 10.3 0.15 92 1978 Apr 16, P. McBride, Green Forest, AR "17°14]6 P V IQ.] )0.5 .061 276 1978 Mar IB, D. Evans, McOonald Observatory, TX +}4° 530 VC 9.310.7 5.5 44 )978.0, Id. Heintz, Swarthmore, PA +14° 631 VC 9.810.2 1.4335 )978.0, 1L Heintz, Swarthmore, PA "14° 639 V C ]0.4 11.6 ).3 208 1978.0, H. Heintz, Swarthmore, PA +}4°2]67 VC 9.912.0 7.5 6 1978.3, Id. Heintz, Swarthmore, PA J 00399 VC)1.811.8 3.9 61 1978.0, hi. Heintz, Swarthmore, PA J 02832 T K 10.8 10.8 0.05 )06 1978 Apr 16, P. Maley, Houston, TX Anonymous V C 10.2 10.8 2.3 349 1978.3, 1A. Heintz, Swarthmore, PA

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