THE COMET’S TALE
Newsletter of the Comet Section of the British Astronomical Association
Volume 9, No 1 (Issue 17), 2002 April
JOEL HASTINGS METCALF MINISTER, HUMANITARIAN, ASTRONOMER
Richard R Didick
Joel Hastings Metcalf was born in The following account, taken used with either a single prism or Meadville, Pennsylvania, on from a newspaper article about a grating, both of which were January 4th, 1866, the son of him when he lived in Taunton, is provided. Lewis Herbert and Anna (Hicks) somewhat dubious since he Metcalf. Lewis was a Civil War actually bought the 7-inch In the observatory at Keesville, Veteran, a soldier who lost a leg refractor. "When but 14 years old the instrument was mounted in a at the first battle of "Bull Run" he built a telescope and ground very substantial dome, being and was held at Libby prison until out a lens with which he was able fastened to a fine cut granite base exchanged and discharged. to observe with success all the weighting about a ton. In a principal heavenly bodies. This February when Lake Champlain At the approximate age of 14, Joel was a small two-inch lens. His had frozen over, the whole outfit Metcalf borrowed Richard next attempt was a three-inch lens was loaded on sleds and started Proctor's book, Other Worlds and he later made one of three across the Lake on the ice. The Than Ours, from his Sunday and a half inches, which he ice was thick enough - but there school library which led him to an subsequently sold to Harvard are always long cracks in the interest in astronomy. This College. He followed up these Lake due to expansion and interest was further inspired by two with a seven-inch visual contraction! These cracks will the conjunction of Jupiter and instrument." (This refractor was sometimes run out as far as four Mars on May 7th, 1879, when the purchased at an auction in miles from the islands. The planets were slightly over one Keesvile, New York, as moving went well until off Juniper degree apart, and/or July 22nd, mentioned below). Island, when the large sled having 1881, when the two planets were the dome and the cut granite pier separated by only seven minutes In his 1906 Popular Astronomy fell into a crack, and would have of arc. article the Reverend also provides gone to the bottom but for the a very informative account of the projected sides of the dome which It is said that he made his first transportation of his 7 inch Alvin reached out to the solid ice! telescope at the age of 14. Clark across the ice of Lake There the load stuck with the Though he does not give his age, Champlain. This is that account water within a foot of the top of this version of his experience in in his words: "In 1901 he was the dome until after three days making a telescope is taken from fortunate enough to come into when, by laying timbers on the his own article written in "Popular possession of a seven-inch ice, and rigging derricks, the Astronomy" magazine 1906, vol. equatorial manufactured by Alvan whole was secured with the XIV, 'An Amateur's Observatory'. Clark and Sons in 1885. It had exception of the four-inch "The writer's first instrument been the property of Elisha telescope, which now lies buried consisted of a two-inch spy-glass, Arnold, a wealthy amateur peacefully in the bottom of the by a French maker, which glass astronomer of Keesville, N.Y., and Lake! he mounted equatorially. He after his death his executors sold Continued on page 9 obtained a high power (100) it at a nominal sum. The negative eye-piece from Alvan telescope had been little used and Contents Clark and Sons, which showed was practically as good as new Comet Section contacts 2 enough planetary detail to keep with all the excellence which one Section news 2 up his interest. A few years after expects from the Clark glasses. In this he was fortunate enough to addition to the equatorial, which Tales from the past 3 get a three and five eighths inch was the best for the size the Professional tales 4 glass by Henry Fitz; this he also Clarks make, the outfit contained Meeting report 6 mounted equatorially and enjoyed a small transit instrument, a four- Joel Metcalf (Cont) 9 for many years". inch telescope with an altazimuth Review of observations 12 mounting, a fine micrometer, and a spectroscope which could be BAA COMET SECTION NEWSLETTER 2 THE COMET'S TALE
Comet Section contacts
Director: Jonathan Shanklin, 11 City Road, CAMBRIDGE. CB1 1DP, England. Phone: (+44) (0)1223 571250 (H) or (+44) (0)1223 221400 (W) Fax: (+44) (0)1223 221279 (W) or (+44) (0) 1223 571250 (H) E-Mail: [email protected] or [email protected] WWW page : http://www.ast.cam.ac.uk/~jds/
Assistant Director (Observations): Guy Hurst, 16 Westminster Close, Kempshott Rise, BASINGSTOKE, Hampshire. (and also Editor of RG22 4PP, England. The Astronomer magazine) Phone & Fax: (+44) (0)1256 471074 E-Mail: [email protected] or [email protected]
CCD Advisor: Nick James, 11 Tavistock Road, CHELMSFORD, Essex. CM1 5JL, England. Phone: (+44) (0)1245 354366 E-mail: [email protected]
Photographic Advisor: Michael Hendrie, Overbury, 33 Lexden Road, West Bergholt, COLCHESTER, Essex, CO6 3BX, England Phone: (+44) (0)1206 240021
Subscription to the Section newsletter costs £5 for two years, extended to three years for members who contribute to the work of the Section in any way, for example by submitting observations or articles. Renewals should be sent to the Director and cheques made payable to the BAA. Those due to renew should receive a reminder with this mailing.
Section News from the Director
Dear Section member, interview for the Today in association with the George programme at 7:40 on a Saturday Alcock memorial lecture. For once I haven't visited the morning. John Humphreys gave Antarctic this winter, but at least me a much easier time than the Since the last newsletter the beginning of January saw a majority of his political observations or contributions have spell of cold weather that froze interviewees! Several newspapers been received from the following the East Anglian fens near have also been after information. BAA members: James Abbott, Whitlesey and allowed me to join Sally Beaumont, Neil Bone, team-mates from the University The revised edition of the Section Owen Brazell, Denis Buczynski, Ice Hockey Club on the ice. Guide to Observing Comets was Roger Dymock, Kenelm England, Generally however the weather finally finished a few days before Len Entwisle, James Fraser, here has been very frustrating, Astrofest. With 58 pages and Mario Frassatti, Mike Gainsford, with far too few gaps in the cloud colour covers, it is packed full of Maurice Gavin, Massimo to glimpse the batch of recent information, much of it revised Giuntoli, Peter Grego, Werner discoveries, though April has seen since the last edition, so do buy a Hasubick, Guy Hurst, Nick a great improvement. In copy. In particular I urge you James, Geoffrey Johnstone, particular the amateur discoveries to read and implement the Gordon MacLeod, Brian of 2002 C1, 2002 E2 and 2002 F1 reporting guidelines. It takes Manning, Steve Martin, Cliff fully confirm the point that I have Guy and myself a lot of time to Meredith, Martin Mobberley, been making that LINEAR and reformat the observations of many Gabriel Oksa, Roy Panther, Robin the other search teams are not people who nearly get it right, but Scagell, Jonathan Shanklin, David covering the entire sky and there not quite, and we would much Strange, Melvyn Taylor, John is still plenty of opportunity for rather spend the time observing! Vetterlein, Alex Vincent and amateur discovery. Who will The Guide is available for £4, Graeme Waddington and also make the next discovery from post free, from the BAA Office. from: Jose Aguiar, Alexandre these shores ? Amorim, Alexander Baransky, The Section meeting in February Sandro Baroni, Nicolas Biver, C/2002 C1 has generated a lot of was a great success and full Reinder Bouma, Nicholas Brown, media interest, with items about it reports are presented for those Jose Carvajal, Tim Cooper, in many of the broadsheet who were not able to come. The Matyas Csukas, Mike Feist, newspapers, mostly following on format of Section meeting, lunch Rafael Ferrando, Sergio Foglia, from a Society for Popular and BAA main meeting seems to Stephen Getliffe, Antonio Astronomy press release. I did an have been appreciated and I will Giambersio, Guus Gilein, Bjorn interview about the comet for the try and make similar Granslo, Roberto Haver, Michael BBC2 programme 'Final arrangements for the next Section Jager, Andreas Kammerer, Heinz Frontiers' and you may have seen meeting, which is provisionally Kerner, Attila Kosa-Kiss, Gary this at the beginning of the month. scheduled for May 2003, possibly Kronk, Martin Lehky, Rolando This was followed by a live Ligustri, Pepe Manteca, Michael BAA COMET SECTION NEWSLETTER 2002 April 3
Mattiazzo, Maik Meyer, Antonio 19P/Borrelly, 44P/Reinmuth, (LINEAR), 2002 C1 (Ikeya- Milani, Andrew Pearce, Maciej 51P/Harrington, 65P/Gunn, Zhang), 2002 E2 (Snyder- Reszelski, Tony Scarmato, Hirita 77P/Longmore, 96P/Machholz, Murakami) and 2002 F1 Sato, Carlos Segarro, Giovanni 1999 U4 (Catalina-Skiff), 1999 (Utsunomiya). Sostero, Graham Wolf and Seiichi Y1 (LINEAR), 2000 SV74 Yoshida (apologies for any errors (LINEAR), 2000 WM1 As a postscript to the end of my or omissions). Without these (LINEAR), 2001 A2 (LINEAR), first paragraph, I was inspecting contributions it would be 2001 B2 (NEAT), 2001 HT50 SOHO images on April 12 when I impossible to produce the (LINEAR-NEAT), 2001 K5 noted a comet entering the C3 comprehensive light curves that (LINEAR), 2001 MD7 field, moving slowly up and to the appear in each issue of The (LINEAR), 2001 N2 (LINEAR), left. This turned out to be an Comet’s Tale. I would welcome 2001 OG108 (LONEOS), 2001 independent co-discovery, observations from any groups Q2 (Petriew), 2001 Q5 (LINEAR- although SOHO policy is that which currently do not send NEAT), 2001 Q6 (NEAT), 2001 only the first observer receives observations to the BAA. R1 (LONEOS), 2001 R6 credit. (LINEAR-Skiff), 2001 TU80 Jonathan Shanklin Comets under observation (LINEAR-NEAT), 2001 W2 include: 7P/Pons-Winnecke, (BATTERS), 2001 X1
Tales from the Past
This section gives a few excerpts April issue announces a new competing for it. [A C D from past RAS Monthly Notices publication 'Cometic Orbits, with Crommelin and P H Cowell were and BAA Journals. copious notes' by Edward J subsequently awarded the Cooper, which had 786 orbits for Lindemann prize for their work on 150 Years Ago: Mr Graham got 198 distinct comets, and cost 5s the comet's orbit.] He also agreed observations of Encke's comet on (25p) [The 14th edition of the that it would be worth looking for the 23rd and 24th inst [Jan], and Catalogue of Cometary Orbits has meteors, but didn't know if any states that the proximity of a ninth some 2000 orbits for 1500 comets were seen. At the next meeting W magnitude star troubled him very and costs 4400p] F Denning pointed out that the much; its light weakened that of May Aquarids were in fact the comet considerably. He adds 100 Years Ago: In the October associated with Halley's comet. that he never before had been so comet notes is recorded 'Prof Hale The April Journal records names much impressed with the vapoury writes that the Yerkes Staff are in and instruments of members of nature of such bodies, and that no way responsible for the the Section and these included: W one could readily imagine that the erroneous intelligence of the F Denning, Bristol, 25cm L; John comet of Encke could be position of the great comet in Grigg, Thames, New Zealand; compressed into the compass of a April last, which was circulated in Edwin Holmes, London, 31cm L; nutshell. In the report to the 32nd the daily press. Prof Frost Rev. T E R Phillips, Croydon, AGM it was noted 'that Faye's suspected a comet-like object 24cm L; Dr R J Ryle, Brighton, comet on its first return in 1850, north of the sun, but it was much 5cm R. was observed at Cambridge nearly too vague to make any five weeks before it was seen at announcement. However a 50 Years Ago:. The Presidential any other observatory, and the newspaper reporter happened to Address by Dr Gerald Merton, at observations were continued till be on the premises, and got wind the October AGM was on the March 4 of last year. Great credit of it; his zeal outran his subject of Comets and their is deservedly given to the discretion, and the erroneous Origins. He appeared to favour assistants at the observatory, for position was distributed the flying sandbank model, the manner in which these broadcast.' The December although some of the fragments observations were secured under Journal has a report on the Great had to be at least a kilometre circumstances of unusual Comet of 1901, which from the across. He mentioned Whipple's difficulty. An interesting paper description was reminiscent of recent paper which presented the 'On the supposed Period of Hale-Bopp. There was much model of a conglomerate of ices Revolution of the Great Comet of discussion of the comet's tails and and dust. He commented that 1680' by Mr Hind appeared in the it seems to have had a prominent Whipple "has tried, perhaps March issue of MN. This was a ion tail or tails. Mr E Walter successfully - I am not competent spectacular comet and its Maunder followed this up in to judge - to show that the various appearance had attracted the February by describing Professor physical activities of a comet can attention of Newton, which Bredikhine's theory of comet tails. be accounted for." At the perhaps lead to his gravitational Dr D Smart presented a paper on February meeting Dr Merton gave theory. Halley thought it might the return of Halley's comet at the news of some recent comets. be periodic and associated it with December meeting, at the request Gordon Taylor had made a naked a comet which had appeared in of Mr Crommelin. He noted that eye observation of P/Schaumasse 1106 and perhaps in 531. The a meteor shower might occur at its recent favourable return. author discusses the observations, around May 17, with a radiant [the comet appears to have and concludes that if Halley had near z Aqr. Mr Crommelin outburst at this return] Dr had access to them he might have commented that there was a prize Steavenson remarked that comet come to a different conclusion for the best theory of the comet, Wilson-Harrington appeared about its possible periodicity. but he didn't know if any similar to drawings of the Great [Vol XII, No 5, pp 142-150]. The Members of the Association were Comet of 1882, but on a smaller BAA COMET SECTION NEWSLETTER 4 THE COMET'S TALE scale. A member of the audience, 10, aged 51, from a heart attack. his searches from a mountain top Mr H Thomson responded that "I He graduated from the Kyushu site, some 10 km from where he can remember well seeing the Industrial University, where he lived, using a pair of 25x150 1882 comet! It was one of the studied photography and worked Fujinon binoculars. After his first astronomical observations I as a lithographer for a regional discovery he became head of the ever made." newspaper in Kagoshima. He municipal observatory at Aira began comet hunting in 1988 near his home. He continued Obituary: Yuji Hyakutake, the when he lived in Fukouka, but comet hunting, but without further discoverer of the spectacular moved to Kagoshima, which is success. He is survived by his comet that graced our skies in the 1000 km south-west of Tokyo, to wife Shoko and two sons. spring of 1996 died on 2002 April get darker skies. He conducted
Professional Tales
Subaru Approaches Origin of therefore contain information on Watanabe of the National Comets - First Estimate of the their parent ammonia molecules. Astronomical Observatory of Formation Temperature of Japan, and a member of the team Ammonia Ice in a Comet Molecules like NH2 and NH3 who performed this research, says National Astronomical which contain two or three "The brand new methods using Observatory of Japan: Science, hydrogen atoms are classified as NH2 molecules have great November 2nd, 2001 either "ortho" or "para", potential for studying the origin of depending on whether the comets. I have a high expectation Observations made with the High- quantum mechanical spins of the for future results obtained by Dispersion Spectrograph (HDS) hydrogen atoms are aligned or these methods, especially for of Subaru Telescope have, for the not. The ortho-to-para ratio short-period comets which are first time, allowed astronomers to strongly depends on the physical thought to have a different origin measure the formation environment, and would have from long-period comets such as temperature of ammonia ice in a been preserved when the Comet LINEAR." comet. The temperature of 28 ±2 molecules were confined into the Kelvin (about -245°C) suggests icy cometary nuclei. The More on comet 19P/Borrelly that Comet LINEAR (C/1999 S4), observed ratio can therefore (An amalgamation of reports from was formed between the orbits of reveal the temperature at the time the NASA press office, The Saturn and Uranus. These the ice was formed. American Association for the observations provide us with not Advancement of Science, only direct evidence of the Molecules in the ortho and para Astronomy.com and Space.com) environment in which the comet states emit radiation at was born, but also establish brand wavelengths that are very close NASA scientists have strung new methods for probing the together, but subtly different due together images of comet Borrelly origin of comets. to the differences in alignment to produce short movies of the between the spins of the hydrogen comet as it travels through space. Comet LINEAR was discovered atoms. The resolving power of In one clip, the bare, rocky, icy in 1999 by the Lincoln Near Earth HDS is high enough to separate nucleus wobbles back and forth to Asteroid Research project these lines and determine how reveal its textured surface, with (LINEAR), operated by the MIT much light is being emitted by some smooth and some bumpy Lincoln Laboratory. A team of molecules in the ortho and para landscapes. The observations researchers from the National states. Using code written by Mr. were taken when NASA's Deep Astronomical Observatory of Hideyo Kawakita of the Gunma Space 1 spacecraft was between Japan, the HDS group, and the Astronomical Observatory, the 3,700 and 9,500 kilometres from Gunma Astronomical Observatory strengths of the emission lines the comet in September 2001. made spectroscopic observations from NH2 could be modeled and of Comet LINEAR on July 5th, compared with the observations to In the second clip, jets of gas and 2000, during the commissioning determine the ratio of ortho to dust shoot from all sides of the phase of HDS, when the comet para molecules in Comet comet's nucleus as it rotates a was bright. LINEAR. Furthermore, the team quarter turn. The biggest jet, investigated the ortho-to-para shooting from the central sunlit The team concentrated on the ratio of the parent NH3 molecules part of the comet, is probably in emission lines produced when and estimated that the formation line with the axis around which NH2 molecules which have been temperature of the ammonia ice to the nucleus rotates. This large jet previously excited, lose some be 28 ±2 Kelvin, which suggests is eroding the central part of the energy and emit light at a series of that Comet LINEAR was formed comet, smoothing parts of the characteristic wavelengths. between the orbits of Saturn and terrain into rolling hills. The Previous studies indicate that Uranus in the primordial Solar erosion will eventually break the NH2, which consists of one System nebula. comet into pieces. Coarsely nitrogen and two hydrogen atoms, textured parts of the comet at both is produced when the powerful Until now, the formation ends are geologically inactive Solar UV rays free a hydrogen temperature had only been areas. atom from the ammonia (NH3) determined for water ice in gas which is constantly boiling off comets, and this is the first time The visible jet shoots out about 60 the comet. The emission lines of that it has been measured for kilometres from the 8 kilometre, the NH2 molecules should another molecule. Dr. Jun-ichi potato-shaped comet. Oddly, BAA COMET SECTION NEWSLETTER 2002 April 5 material emanates mostly from During the flyby, Deep Space 1 the comet's fourth type of feature: the middle of the comet, whereas measured the interaction of the dark, flat-topped mesas scientists had expected a more comet's coma with the solar wind. surrounded by bright slopes. even distribution. Adding to the As expected, the solar wind According to Britt, the smooth perplexity, the primary jet does flowed around the comet, but the terrain and slopes probably reveal not point toward the Sun, as nucleus was not at the centre of the comet's freshest material and expected based on observations of the flow. "The formation of the are the likeliest source of its jets. other comets. Borrelly dishes out coma is not the simple process we so much material from its once thought it was," said David Britt pointed to another curious midsection -- some 2 tons every Young of the University of characteristic on Comet Borrelly's minute -- that it will likely break Michigan, Ann Arbor. nucleus. Several ridges and in half within 10,000 years, says fractures cut across the comet's Laurence Soderblom, U.S. Nordholt says that while Halley slimmest section, which separates Geological Survey researcher who and Borrelly are quite different in its two lobes. Jürgen Oberst of led the imaging team. terms of their exact composition Germany's DLR Institute of Space and behaviour, they are all-in-all Sensor Technology and Planetary On average, Borrelly's nucleus very much alike, confirming Exploration, added that a three- reflects a low 2.5% to 3% of the suspicions that most comets dimensional stereo elevation map light that strikes it, says Deep formed in a similar manner and at of the nucleus shows that the Space 1 project scientist Robert a similar time - back when the smaller end of the bowling-pin- Nelson of the Jet Propulsion solar system was gathering itself shaped nucleus is not aligned with Laboratory in Pasadena, together some 4.6 billion years but tilted (by 30º to 50º) relative California. That's darker than the ago. "Borrelly seems to come to the larger half. Britt and Oberst 4% reflectance measured for from the same primordial stuff suggest these observations Comet Halley by the European that Halley comes from," she said. indicate Borrelly's nucleus may Space Agency's Giotto spacecraft actually be a contact binary - in 1986, and it rivals the dark composed of two pieces loosely hemisphere of Saturn's odd moon bound to each other. Iapetus and the rings of Uranus. Struggling to find a substance on Comets are sometimes described Earth with shades as dark as as "dirty snowballs," but the close Borrelly's, Nelson could come up flyby detected no frozen water on with only one thing: photocopy Comet Borrelly's surface. It has toner. plenty of ice beneath its tar-black surface, but any exposed to The real surprise was a cluster of sunlight has vaporized away, say spots on the comet's nucleus that 19P/Borrelly and topographic map scientists analyzing data from are three times darker than the rest Deep Space 1, managed by of it, reflecting less than 1% of "The average geometric albedo is NASA's Jet Propulsion light. Analysis shows that these black, black, black, and ranges Laboratory, Pasadena, Calif. spots are real, not just shadows or from extremely black to very pits, says Deep Space 1 imaging black," said University of "The spectrum suggests that the scientist Larry Soderblom of the Tennessee geologist Dan Britt, surface is hot and dry. It is U.S. Geological Survey in who described the nucleus's color surprising that we saw no traces Flagstaff, Arizona. The team as being like that of photocopier of water ice," said Dr. Laurence suspects that something in the toner. Amidst Borrelly's Soderblom of the U.S. Geological comet's texture explains its inky gloominess, however, Britt Survey's Flagstaff, Ariz., station, blackness, as solid materials don't managed to identify four main lead author of a report on the normally reflect so little light. types of landforms on the strange Borrelly flyby results appearing in mini-world. the online edition of the journal A fluffy or honeycombed texture Science. "We know the ice is is the most likely explanation, Mottled terrain covers the there," he said. "It's just well- agrees space physicist Tamas extended comet's far opposite hidden. Either the surface has Gombosi of the University of ends, which are darker than been dried out by solar heating Michigan, Ann Arbor, a veteran Borrelly's mid-section. These and maturation or perhaps the of the Giotto mission. That rough areas are filled with bowl- very dark soot-like material that texture traps and absorbs most shaped depressions, hills, streaks covers Borrelly's surface masks photons of light, Gombosi says. aligned with the nucleus's long any trace of surface ice." Planetary scientists expect that axis, and notable variations in mixtures of dust and ice turn brightness. The ends lack any "Comet Borrelly is in the inner black after billions of years of strong association with the solar system right now, and it's irradiation by photons and high- comet's jets. Among the mottled hot, between 26 and 71 degrees energy particles from the sun, but terrain at the ends of the comet's Celsius, so any water ice on the they don't yet know the details of nucleus are spots darker than surface would change quickly to a that composition. Answers may anything else on Borrelly. These gas, " said Dr. Bonnie Buratti, come from Deep Impact, a black patches reflect just 0.7 to 1 JPL planetary scientist and co- projectile that will slam into percent of incoming light, Britt author of the paper. "As the Comet Tempel 1 in July 2005, reported. components evaporate, they leave when a flyby spacecraft will study behind a crust, like the crust left material beneath its surface. The middle of the nucleus behind by dirty snow. It seems to consists of Borrelly's brightest and be covered in this dark material, smoothest terrain. It also contains BAA COMET SECTION NEWSLETTER 6 THE COMET'S TALE which has been loosely connected Communications and Public properties of the two types of with biological material." Buratti Affairs bodies are different. Objects in said. "This suggests that comets the dynamically intermediate might be a transport mechanism The CONTOUR spacecraft has Centaur class have optical colors for bringing the building blocks of been shipped to Goddard SFC for like those of KBOs, while the life to Earth." Comets may have prelaunch testing; on its way to a color distribution of candidate played an important role in July 2002 launch. dead comets is indistinguishable supplying organic materials that from that of the cometary nuclei. are required for life to originate. After launch, the solar-powered We infer that the surfaces of CONTOUR will visit at least two KBOs are modified upon entry to Soderblom points out that comets as they travel through the the inner solar system. We Borrelly's old, mottled terrain inner solar system. From as close consider several mechanisms and with dark and very dark spots -- as 100 kilometres, the spacecraft conclude that the color change is different shades of black -- are will take the most detailed most likely caused by the rapid apparently inactive. Ground- pictures ever of a comet's nucleus; burial of ancient surface materials based observations estimated that map the types of rock and ice on exposed in the Kuiper belt. The 90 percent of Borrelly's surface the nucleus; and analyze the distinctive, ultrared material that might be inactive, and the composition of the surrounding is present on the surfaces of some observations taken by Deep Space gas and dust. CONTOUR's KBOs is absent on the cometary 1 show that this is indeed true. targets include comet 2P/Encke in nuclei. Copyright © 2002 November 2003 and Institute for Scientific Information "It's remarkable how much 73P/Schwassmann-Wachmann in information Deep Space 1 was June 2006, though the spacecraft Cometary Outbursts - search of able to gather at the comet, can also be sent toward an as-yet- probable mechanisms - case of particularly given that this was a undiscovered comet. The data 29P/Schwassmann-Wachmann bonus assignment for the probe," will provide clues into the P Gronkowski: AN 323 (2002) 1 said Dr. Marc Rayman, project similarities and differences manager of the mission. Deep between comets. This paper comes up with another Space 1 completed its original theory of cometary outbursts. The goal to test 12 new space From Kuiper belt object to author suggests that an outburst is technologies and then earned cometary nucleus: The missing triggered by polymerisation of extra credit by achieving ultrared matter. Jewitt DC: HCN (either by uv light or solar additional goals, such as the risky Astronomical Journal 123 (2): wind electrons), which heats the Borrelly flyby. "It's quite exciting 1039-1049 Feb 2002 nucleus and triggers a now as scientists working with transformation of amorphous this rich scientific harvest turn We combine new and published water ice into cubic ice. This data into knowledge." data to show that the optical color gives rise to further heating and distributions of cometary nuclei leads to the release of trapped CO Contour spacecraft on its way and Kuiper belt objects (KBOs) or CO2 and dust. However, the to prelaunch testing. The Johns are significantly different. The author admits that the mechanism Hopkins University Applied nuclei are, as a group, bluer than cannot explain outbursts at small Physics Laboratory, Office of the KBOs, indicating that the heliocentric distances. surface chemical and/or physical
Section Meeting Report, 2002 February 23
Members of the Comet Section Guide was a greatly expanded comet tails. He showed an and other comet enthusiasts met at version of the first edition and he overhead of 1996 B2 the Scientific Societies Lecture particularly drew attention to the (Hyakutake), and asked us to Theatre in Saville Row on the section on formatting estimate the length in 'daylight' morning of February 23. This observations sent by email. Badly and 'dark' conditions. The was a new venture for the BAA, formatted observations took up estimated length varied from 3.5 with the hope that a morning hours of his and Guy Hurst's time to 8°, with longer tails in dark Section Meeting would tempt every week. Once formatted conditions. He has provided the more people to attend the correctly he was able to produce following report: afternoon main BAA Meeting. light curves from the observations The doors opened by 10:30 and a and showed those for 2000 WM1, steady stream of people arrived 2001 OG108 and 2002 C1, which Estimating tail for coffee and biscuits and a should be readily observable in lengths of comets chance to chat. In total 33 people the coming months. He signed the register, though concluded by mentioning the perhaps there were a few more recently discovered Marsden and Guy M Hurst, Assistant than that present. Meyer groups of SOHO comets, Director, BAA Comet Section of which the former were The Director, Jonathan Shanklin, potential NEOs, with 1999 J6 The Ordinary BAA meeting held opened the formal meeting at approaching to within 0.03 AU of in London on Saturday February 11:00 and immediately apologised the Earth. 23, was preceded, as an for the lack of comet guides, experiment, by a Comet Section which were locked up in the BAA Guy Hurst then introduced a meeting in the morning and this Office. The new edition of the practical experiment in observing was very well attended. BAA COMET SECTION NEWSLETTER 2002 April 7
The message from the BAA With Jonathan’s agreement, I Leaving the lights on in the meeting was that comet observing conducted a practical experiment lecture theatre, ‘votes’ were cast is not quite as difficult as many on the estimation of the tail length which ranged from 4.0 to 6.5 people attending, who were new of Comet Hyakutake from degrees. Thirty people were to the subject, might have studying a photograph secured by brave enough to participate and supposed. However a careful Arto Oksanen (Finland) of 1996 the average tail length derived technique is needed and for tail April 9 and which was shown on was 4.9 degrees. When they lengths making estimates against screen. At that time the comet was dimmed the lights, although two pairs of stars and averaging situated in Perseus near beta, leaving them on sufficiently to the results might assist. To signify probably better known to most of still see the map, this time the the conditions, it is also helpful to us as Algol. average was 5.9 degrees. note the limiting magnitude in the field of the comet. Audience members were supplied For comparison, 12 of my with a map of the same area of students, in a brightly light Thank you to all who participated sky, but without the comet classroom on 2001 November 5, in the experiment! depicted (figure 1), which had had an average of only 4.02 been derived from CD ROM degrees. Five visual observers software, Guide 7.0 by Bill Gray agreed use of their data for the The next speaker was Giovanni of Project Pluto. classroom experiment and Sostero, who observes from estimates recorded on that date Remanzacco, Italy. The site Figure 1: Field of Comet from Mauro Zanotta, Bjorn suffers from severe light pollution Hyakutake on 1996 April 9 Granslo, Melvyn Taylor, James but has 90 useable nights per year. He uses a Baker-Schmidt camera and a Newtonian-Cassegrain telescope with a local group of observers. He has provided the following summary of his talk.
CCD imaging of comets Giovanni Sostero (Remanzacco Observatory, Italy)
The rapid development of In reality, this experiment had Fraser and David Storey gave an optoelectronic technologies has been conducted for the first time average of 5.13 degrees. also proved to be very helpful for with students attending my amateurs astronomers. A classic evening class in Basingstoke back It is obvious that if one observer 20cm Newtonian scope, fitted on 2001 November 5. We is making estimates in strong light with a CCD camera, can normally anticipated that fireworks might pollution and another from a dark reach down to magnitude 17 in prevent direct viewing of the country site, that the latter will few minutes of exposure time, night sky so an in-class practical usually record a much longer tail. even from moderately light exercise was devised as a However another effect, which polluted backyards. In cometary substitute! may actually bias the observer, astronomy this is a real help, and can occur when the tail is aligned by means of CCDs, amateurs can Estimating tail lengths is quite with a pattern of bright stars, provide additional valuable data difficult but the simplest which was the case here with Fl with at reasonable expense. technique is to select a gap 32 and Fl 30. The brain seems to between two nearby stars which is automatically form a ‘tidy’ image slightly longer than the tail and of the tail just reaching the gap. record a proportion of the star Similar problems can occur with a separation. Figure 1 shows the comet in a densely populated map supplied and two star gaps portion of the Milky Way where with approximate values were mere star asterisms, if arranged in quoted: ‘lines’, can tempt observers to believe the tail is extended much further than is really the case. Fl 30 to Fl 32 = 1 degree Fl 16 to Fl 20 = 37 arc minutes The 20cm Baker-Schmidt camera BAA COMET SECTION NEWSLETTER 8 THE COMET'S TALE
coma. Great care should be taken We can distinguish among two when a comet is showing a dusty very broad fields of applications: tail: in this instance we risk cometary head photometry and including in our aperture part of morphological studies. In the first the tail, and this will produce an instance it is almost mandatory to offset in the total brightness of the provide the CCD camera with an coma. An amateur, measuring a appropriate filter set. Sometimes comet throughout its apparition by unfiltered CCD photometry can means of a CCD and a couple of be helpful without the adoption of standard filters, could provide standard filters (e.g., in the some meaningful information on Remanzacco Observatory monitoring of faint comets) but if the gas/dust production rates of a serious observing program is to the given object, just taking The author would like to thank be undertaken, then a Johnson V regular brightness measurements very much Guy Hurst and Jon filter and a Cousin I filter are the with backyard instrumentation. Shanklin for their invitation and right choice. With the first one Also the development of jets, kind hospitality. we would be able to measure the hoods, halos and similar gaseous emissions of cometary structures within the coma would comae (mainly due to the so be recognisable with CCD called Swan-band emissions) imaging, as well as the fine details Alan Fitzsimmons, was our next while the second is helpful for the sometime developing in the tails. speaker on 'Big Comets and Little monitoring of dusty emissions. In this kind of application, as Comets - How many of each ?', Professional astronomers are well, the adoption of some which he subtitled as a routinely using interference filters standard filters will be helpful, programme to get the most boring with very narrow bandpasses, in because in this way we will be images of comets possible. At 0.5 order to detect the light frequently able to distinguish AU a 1 km comet nucleus spans contribution from single among gassy or dusty features. 0.003" - not even NGST will see molecular species. But For the monitoring of fine details it. It is also hidden by dust - a 2km nucleus will be hidden by unfortunately these filters within the central condensation, a 18 suppress most of the incident light scale of the order of 2 arcsec/px 10 particles, but this amount and for the amateurs very few and a good seeing are mandatory. only weighs 1000 kg and comets will be bright enough to For relatively bright comets, this emission is at 1kg/sec. Most be a suitable target with their kind of observation is also comets produce more. Comets instrumentation. Normally the possible from a heavily light formed beyond Saturn and now measurement of cometary polluted observing site. Some reside in the Kuiper Belt. It needs magnitudes through a CCD software packages are provided a 30 metre or larger aperture camera is performed by means of with rotational gradient telescope to study the smaller the “aperture photometry” algorithms that would enhance the members. Comets are lost by method. In this way, after the subtle details within cometary collision or switching off, they appropriate pre-processing, the heads. Anyway, they should be also shrink, vaporise, split and net amount of ADU is counted treated with great caution, fragment. There are usually more within a selected window centred because without some experience little ones than big ones of anything, or mathematically N(D) on the coma. Similarly we are this kind of image processing a measuring the net ADU values could dangerously enhance the ~ D => Log10 N(
AU, implying it was smaller than some have <0.7% albedo. [This 14:30. There were lots of 1.2 km. 74P doesn't switch off at report is based on my notes and comments that the meeting had all and is <25km. Plotting N vs subject to error, a full report from gone well, so we are planning R10, for D > 3km the slope is 0.32 Alan will appear in the October another one for next year. The implying for every comet bigger Tale.] intention will be to have a than 3 km there are 40 bigger than morning session devoted to 1 km. This implies there are At the conclusion of Alan's talk technical issues for the comet around 400 active comets in the the meeting broke for a splendid Section, with popular talks on inner solar system. The slope for lunch cooked by chef 'Louis'. comets in the afternoon as the NEOs, JFCs and MBAs is around There was plenty of chance for topic of the main BAA meeting. 0.3, which is not collisional, further discussion during the This may include the George however that for TNOs is 0.69 for meal, which was served with a Alcock Memorial Lecture, which D >50 km, but this can't go to glass of wine. By the time we had we hope will be given by a well- small sizes or we would see the finished eating, other astronomers known professional expert on Kuiper Belt. The mass must be were arriving for the main BAA comets. concentrated in large comets, and meeting, which commenced at Joel Metcalf (Continued)
Continued from page 1 her life with "father", titled "A Committee for Brown Nice night For Comets" in the University's Ladd Observatory, in The observatory was installed in January, 1939 issue of "Popular Providence, Rhode Island. Burlington, Vermont, until 1905, Astronomy," which was later when the writer moved to republished in the September, One of the problems that he Taunton, Mass., and then 1979 issue of "Yankee" magazine. sought to follow up on from his presented the house and dome to He served in Burlington, Vermont time at Oxford was that of the University of Vermont, his (1893-1903) where it appears his comparing and recording previous experience in moving it interest in grinding lenses began measurements from photographic not being an encouragement to extensively. He corresponded plates take by "Schurs" of the experiment". with Prof. J. M. Schaeberle at "Praesepe Cluster in Cancer" with Ann Arbour, MI. new photographs taken from Lick The 13-inch triplet Observatory. He proposed this to Being at risk of a nervous Prof. Campbell, at Lick As a telescope maker he has breakdown, he interrupted his Observatory in a letter dated graced the astronomical world ministry for a year in 1902 to August of 1904. with an 8-inch f/80 inch ("broken- attend Oxford University where backed") comet hunter kept at he is said to have attended an His First Comet, 1906 VI, a South Hero, Vermont for use average of twenty-five lectures Record Breaking Photograph during his summer vacations, a weekly on philosophy and 10- inch photographic triplet now religion. He was also given the He and his family resided at 54 newly restored and in the keys to the observatory by Summer Street where 38 of his 41 possession of the Boyden Professor Turner, spending much asteroids were discovered. The Observatory, University of the time on astronomical problems. last four were discovered from Orange Free State, Bloemfontein, After Oxford, he took a year off to Winchester, Mass. Taunton was South Africa, a 12-inch doublet rest before returning to the also where he discovered the first (which he used in Taunton, ministry at the First of his 5 comets, 1906VI using his Mass.) now located at Oak Ridge Congregational (Unitarian) church homemade 12-inch doublet, Observatory, Harvard, in Taunton, Massachusetts refracting telescope. Massachusetts, and a 16-inch (1904/5-1910). Taunton at that f/5.25 doublet, also located at Oak time was one of, if not the largest, This comet was discovered in Ridge Observatory. He was in the manufacturer of silver products in Eridanus on November 15th, process of making the 13-inch the United States. It's streets are 1906. (Metcalf states in his triplet used in the discovery of the still lined with the many Victorian franticly written observing planet Pluto when he died in 1925 style homes, with long and records that the comet was (it was completed by C. A. Robert extended porches where the photographed on November 14th, Lundin of Alvan Clark and Sons). residents would sit and pass away at 3h 59m -1°). With a discovery the day conversing with the magnitude of 11.5, having a He graduated from Meadville passers-by. round, 2 arcminute coma and a Theological Seminary in 1890, distinct central condensation. It then continued his education at It was from Taunton that most of had passed perihelion on October Harvard Divinity School and his asteroids were discovered and 10, 1906. After discovery the obtained his degree of Ph.D. at where his relationship with comet slowly faded as it Allegheny College in 1892. He Harvard Observatory appears to continued on its path away from married Elizabeth S. Lockman, of have begun. He was also a the sun. By December 10th the Cambridge, Massachusetts in member of the Visiting comet had reached 12th September of 1891. They had Committee of Harvard's magnitude. It was last seen on two children, a son, Dr. Herbert E. Observatory. Reverend Metcalf January 16th, 1907 at 13th Metcalf of San Leandro, enjoyed a lasting friendship and magnitude. Mr. Kronk goes on to California, and a daughter, Rachel professional relationship with Dr. say that it is worth mentioning Metcalf Stoneham. She later Pickering. He also became a that; M.E. Esclangon of Bordeaux wrote a wonderful article about member of the Visiting Observatory observed two BAA COMET SECTION NEWSLETTER 10 THE COMET'S TALE
Called To Winchester, Massachusetts. Some more Comets and a War!
He was next called to Winchester, Massachusetts (1910-1920), located just north of Boston, where many of his sermons and editorials were more than occasionally published in the "Winchester Star," the local newspaper.
His other four comets were visually discovered from South Hero, Vermont, where the Unitarian church had a summer camp. It was at this camp where he did most, if not all, of his lens grinding and comet hunting. He even expressed in an interview that he searched for comets "in Vermont, only when he was on vacation"!
His next comet, 1910IV was nebulous objects near the comet rotational period may only go discovered on August 9th, at on November 22nd which he through periods of flair ups when magnitude 8.5 and having a described as easily visible. One these areas of fresh material are diameter of about 2 arcminutes. was said to be elongated with a exposed. He used his trusty "broken- length of 30 arcseconds, the other backed" comet seeker to discover was circular, with a diameter of One of the greater surprises this long period comet. This 20 arcseconds. The objects were during my research of the comet was discovered in not detected the next evening, so Reverend's life was to learn that Hercules. The comet's brightness he concluded that water was he held the record for amateur was estimated as being between between the objective lenses. A astro-photographical 9.5 -10th magnitude. The periodic orbit was computed, but accomplishments. This he did appearance of the comet depended the comet was not recovered. from Taunton, Massachusetts, on the instrument used through according to the unidentified the month of August, ranging In early January, 1991, from newspaper account from the "Old from 8th to 11th magnitude, with Cloudcroft, New Mexico Howard colony historical society," a nuclear region ranging from Brewington walked out to his 16 Taunton, Mass. "The most expert stellar to extremely diffuse. inch reflector and began his amateur astronomer in the However, observations of its tail search efforts for another new country. This is the tribute paid length remained constant as comet. (He had just discovered by Professor Pickering of having a length of 1.5 arcminutes one on November 16, 1989.) It Harvard College to a young Bay through the 11th. The comet was during this search that he State Minster. With a telescope reached perihelion on September discovered another comet. After which he himself invented and 16th, at 10th magnitude. The receiving the report at the built, the Rev. Joel H. Metcalf of coma remained at 2 minutes of Smithsonian Astrophysical Taunton, a young Unitarian arc. During the month of October Observatory in Cambridge, Mass., clergyman, has recently startled the tail was reported to have a Dr. Brian Marsden noticed that the scientific world by length of 18 minutes of arc, the orbits to date matched those of photographs he made of Phebe, sustaining a magnitude of 10. the lost Comet Metcalf 1906VI. one of the satellites of the planet The comet remained as such Therefore, although Brewington Saturn, breaking all records for through November and hadn't discovered a new comet, he astronomical camera work. The December. January 29th brought did succeed where so many had smallest telescope to reflect the on an outburst, bringing the failed, in the recovery of the image of the ninth satellite has magnitude to 9.5, and 9.3 by Reverend's only short period been until now the huge 24-inch February 2nd. At that time the comet, now designated instrument at the Harvard coma diameter was estimated at 97P/Metcalf-Brewington. Also in Observatory at Arequipa, Peru, 1.5 minutes of arc, having a tail reference to M.E. Esclangon of but the Rev. Mr. Metcalf, with a length of 5 minutes of arc. By Bordeaux Observatory, observing 12-inch glass of his own make and late March the comet's magnitude "two nebulas objects" (mentioned a little observatory erected in his was estimated at 11, by mid- above), it's an interesting note that backyard, has accomplished the April, 11.3 and by late May, 13th when this author conversed with feat which for years has been magnitude. It was last seen on Dr. Marsden, after reading about regarded by scientists as June 23rd, close to magnitude 14. the recovery of this comet, Dr. impossible". Marsden proposed that the comet Back on vacation again in South may have divided at one time and Hero, Vermont, on September that because of it's possible 2nd, 1913 the reverend observed BAA COMET SECTION NEWSLETTER 2002 April 11 through his comet-seeker and "When we broke the rush of in the ground, to find the chateau, discovered 1913 IV in Lynx, at Germans over the Metz to Paris except the lower stories, in ruins magnitude 9.5. The comet was road and French were in full and many of our company dead moving slowly northward, and at retreat and when our boys came and wounded. I helped in first aid first was thought to be Comet along they shouted, "La guerre est all that day. The only things to Westphal. By September 9th, the finis. Paris est perdu. Allez vite, eat were the Y.M.C.A. stuff which comet's diameter was estimated etc." Instead of retreating, we we gave them, the wounded and between 5-6 minutes of arc. On advanced and fought the battle unwounded, without money and the 14th of September the comet which centered around Belleau without price, chocolate crackers, passed perihelion at 1.36 AU. As Woods. We relieved the marines etc.- all that we had." the comet approached the earth its for six days, so you can see I was diameter grew to 10 minutes of right in it. In the day time I Rev. Metcalf was later offered arc with a magnitude of 7.5, carried supplies into the woods, and refused a position as an passing within 13 degrees of the alone and with runners, and at officer in the Army out of a desire north celestial pole. After night we sold supplies in the "Y." to continue along with "his boys" perigee, (0.62 AU) on October This place got several hundred 8- at the front. 8th, the comet quickly faded as it inch shells every day. They continued along its retrograde simply peppered the "Y." It got so Coming Home, a Couple More orbit. By October 17th this comet every time I walked out, I made up Comets and Off He Goes faded to magnitude 9.5 and by my mind just what hole or Again.... early November it had faded to depression in the ground I would 10th magnitude. On the 21st of drop into when I heard a shell Brorsen of Altona Observatory, November its magnitude was (you can hear them 5 or 6 Germany discovered a comet on estimated at 11.5. 1913 IV was seconds). July 20th, 1847 at magnitude 9.5, last seen on November 30th. in the constellation Aries. He The second battle of the Marne, observed it as vary faint and very In 1918, Reverend Joel Metcalf that is, the German offensive diffuse without any nucleus. By volunteered to go to France "Rev. beginning on the night of July 14, mid-August, as the comet Joel H. Metcalf of the Unitarian was a tremendous effort on their approached the sun and earth it Church will sail for France the part. For two nights previous, I reached a magnitude of 6.5, week of March 4th. Mr. Metcalf had carried chocolate to the men having a tail length of about 15 will enter the Y.M.C.A. as a on the bank of the river, and for minutes of arc. During that secretary and his duties in the war weeks they had not fired a shot period the comet faded slowly as zone will include, besides the and their trenches in plain sight of it continued toward the sun and regular routine work, hut work where I was seemed deserted. We was last seen on September 13th and giving illustrated travel talks shelled them all the time with a at magnitude 9.5. to the troops ..." (Winchester strafing that must have done some Star, February 22nd, 1918) damage. At 12:15 Monday night This was the first comet that the without an instant's warning they Reverend found, on August 21st, opened with a crash on a 50 mile 1919, after his arrival home from front. It was the most terrible his duty in France on the evening thing imaginable. Like a of January 24th. His home was in thunderstorm and a sudden fall of Winchester, Massachusetts at the rain, the heavens seemed to drop time. This comet was also steel everywhere for 10 miles independently discovered by 5 back of our lines. I was in bed other observers at the time. By (that is on the floor) with my September 5th, the comet came shoes off when the first shells fell. within 0.19 AU of the earth, By the time I got my coat on and having a magnitude of 5.3 and a shoes and got to the door, the coma 15 minutes of arc in court yard was raining shells, so I diameter. As the comet increased rushed through the chateau, its distance from the sun its smashed open a window on the magnitude increased as well. It's Rev Joel Metcalf at the front lee side of the shells and tumbled tail reached a length of 1.5 into a dugout with about 25 others degrees in late September. During the War much of his time who were there. The air reeked However, its coma diameter was spent at the front lines. He with gas, high explosive and decreased. Two days later, on was known to have sung songs mustard. Imagine me, the tears August 23rd, the Reverend was while marching in front of the running out of my eyes from gas, again out searching and came men along marches that were crouching in a corner sitting on a across Comet 1919 V in the sometimes 25 miles in length! He nail (two nails in fact) gasping for constellation Bootes, at 8th was also known to have carried breath, the mask cutting my ears magnitude. Borrelly some of the wounded and their and forehead till they ached. We independently discovered the backpacks as well. Here is part of sat thus for 9 mortal hours, like comet from Marseilles, France. a letter from Rev. Metcalf while Paul praying for the day and the Although the discovery in France, published in "The end of the bombardment, while magnitude was estimated to be Calendar", the Unitarian the wild roar of the shrieking about 8th, most observers reported newsletter. Extracts from Mr. death continued outside. estimates of 9th magnitude, Metcalf's Letters of July 25th and having a coma diameter of 2 28th: At twelve o'clock the worst was minutes of arc. During over and we came out of our holes September, as the comet BAA COMET SECTION NEWSLETTER 12 THE COMET'S TALE approached the sun and earth, it Mass. Unknown (Boston?) Ophiuchi (1922). He died on brightness increased to 8 or 8.5. newspaper, circa ~ 1919.) February 23rd, 1925 at the age of A coma diameter was estimated at 59. 4 minutes of arc. It reached 7th He visited many remote parts of magnitude by November. The the area, travelling by automobile, The author wishes to comet was lost to northern making one remarkable journey acknowledge the help of: Martha observers during late November between Cluj and Bucharest, Hazen, Harvard College as it entered the sun's glare after returning not without peril, with Observatory; Dr. Brian Marsden, the 23rd, reaching perihelion on about $10,000 in currency. He Harvard Smithsonian December 7th (1.12 AU). The made a journey out from Astrophysical Observatory, comet was recovered on the 19th Transylvania to England, Cambridge, Massachusetts; by observers in the Southern returning with supplies. He was Dorothy Schauimberg, Mary Lea Hemisphere remaining visible so loved by the people there that Shane Archives of the Lick until February 3rd, 1920. when two other commissions Observatory; Mike Saladyga, were sent back to the area in 1922 AAVSO; Don Machholz, ALPO; A short time later, he volunteered and 1924, they were continually Gary Kronk. to go back to Europe to assist in asked when Dr. Metcalf would rebuilding the churches in ever return. If you wish to read more of his Hungary. "Boston's most eminent sermons, and/or other articles by amateur astronomer, Rev. Joel H. Home Again, a Few More and about Reverend Metcalf you Metcalf, has deserted his Discoveries and Time To Rest... may visit the Joel H. Metcalf astronomical station on the top of Memorial Homepage at the apartment house in which he It more than appears that the war http://personal.tmlp.com/richard/ lives in Winchester, and has gone and his extensive travelling metcalf.htm. to Hungary on a mission to the throughout the region of Hungary one hundred Unitarian churches had taken a toll on this man's Any additional information about in Transylvania. He is one of a relentless body and spirit. this man will be greatly commission of three appointed by Because this time, on returning appreciated by Richard. Data on the American Unitarian home to the United States, he two areas of his life are very Association and has resigned moved to Portland, Maine, and much needed: they are any from the pastorate of the with a last spark of discovery, he records of his time spent at Unitarian church of Winchester to was able to add at least three new Oxford, and in Cluj, Romania. fill his mission." (Old Colony variable stars to his long list of You may contact him personally Historical Society, Taunton, accomplishments, RV Leonis at: [email protected] (1919), SV Hydri (1921) and WZ
Review of comet observations for 2001 October - 2002 April
The information in this report is a 2001 U1 SOHO (IAUC 7746, 2001 November 6) 2002 G2 SOHO (IAUC 7873, 2002 April 10) synopsis of material gleaned from 2001 U2 SOHO (IAUC 7746, 2001 November 6) 2002 G4 SOHO (IAUC, 2002 ) IAU circulars 7740 – 7880 and 2001 U3 SOHO (IAUC 7746, 2001 November 6) 2002 G5 SOHO (IAUC, 2002 ) The Astronomer (2001 October – 2001 U4 SOHO (IAUC 7746, 2001 November 6) 2002 H1 SOHO (IAUC, 2002) 2002 March). Note that the 2001 U5 SOHO (IAUC 7746, 2001 November 6) were discovered with the SOHO figures quoted here are rounded 2001 U7 SOHO (IAUC 7750, 2001 November 10) LASCO coronographs and have off from their original published 2001 U8 SOHO (IAUC 7759, 2001 November 21) not been observed elsewhere. accuracy. Lightcurves for the 2001 U9 SOHO (IAUC 7759, 2001 November 21) They were sungrazing comets of brighter comets are from 2001 U10 SOHO (IAUC 7759, 2001 November 21) the Kreutz group and were not observations submitted to The 2001 V1 SOHO (IAUC 7759, 2001 November 21) expected to survive perihelion. Astronomer and the Director. A 2001 V2 SOHO (IAUC 7759, 2001 November 21) Some of these comets show no full report of the comets seen 2001 V3 SOHO (IAUC 7764, 2001 December 3) tail at all and it is possible that during the year will be published 2001 V4 SOHO (IAUC 7764, 2001 December 3) some supposed observations of in the Journal in due course. I 2001 V5 SOHO (IAUC 7764, 2001 December 3) Vulcan were actually tiny Kreutz have used the convention of 2001 W3 SOHO (IAUC 7764, 2001 December 3) group comets. designating interesting asteroids 2001 W4 SOHO (IAUC 7764, 2001 December 3) by A/Designation (Discoverer) to 2001 X4 SOHO (IAUC 7797, 2002 January 19) Meyer group comets clearly differentiate them from 2001 X5 SOHO (IAUC 7797, 2002 January 19) Brian Marsden notes on MPEC comets, though this is not the IAU 2001 X6 SOHO (IAUC 7797, 2002 January 19) 2002-C28 that: While 2002 C3, convention. 2001 X7 SOHO (IAUC 7797, 2002 January 19) like some 95 percent of the 2001 X9 SOHO (IAUC 7797, 2002 January 19) comets discovered by SOHO, is SOHO Kreutz group comets 2001 Y2 SOHO (IAUC 7797, 2002 January 19) clearly a member of the Kreutz 1996 V1 SOHO (IAUC 7760, 2001 November 23) 2001 Y3 SOHO (IAUC 7797, 2002 January 19) sungrazing group, it is rather less 1996 Y2 SOHO (IAUC 7807, 2002 January 24) 2001 Y4 SOHO (IAUC 7797, 2002 January 19) appreciated that as many as 11 of 1998 H5 SOHO (IAUC 7842, 2002 March 5) 2001 Y5 SOHO (IAUC 7797, 2002 January 19) the two dozen or so non-Kreutz 1998 H6 SOHO (IAUC7842 , 2002 March 5) 2002 C3 SOHO (IAUC 7839, 2002 March 1) comets discovered by SOHO also 1999 H8 SOHO (IAUC 7839, 2002 March 1) 2002 C4 SOHO (IAUC 7839, 2002 March 1) seem to be interconnected. The 1999 H9 SOHO (IAUC 7839, 2002 March 1) 2002 D1 SOHO (IAUC 7839, 2002 March 1) close temporal pairs C/2000 C2- 1999 J13 SOHO (IAUC 7839, 2002 March 1) 2002 E1 SOHO (IAUC 7850, 2002 March 12) 2000 C5, C/2000 C3-2000 C4 and 1999 K17 SOHO (IAUC 7842, 2002 March 5) 2002 E3 SOHO (IAUC 7862, 2002 March 28) C/2000 Y6-2000 Y7 were 2001 T6 SOHO (IAUC 7750, 2001 November 10) 2002 F2 SOHO (IAUC 7862, 2002 March 28) remarked on when these comets 2001 T7 SOHO (IAUC 7750, 2001 November 10) 2002 F3 SOHO (IAUC 7862, 2002 March 28) were announced (cf. MPEC 2000- BAA COMET SECTION NEWSLETTER 2002 April 13
C52, 2000-C53 and 2001-B08). similarity to that of the Daytime +9.7, for the four clear members There is also the pair C/1999 J6 Arietid meteor stream, with q = of the Marsden group (cf. IAUC (MPEC 2000-F30) and C/1999 0.09 AU and L = 104, B = +10 4832). A more extended U2 (MPEC 1999-U29), comets (degrees, J2000.0; cf. MPEC relationship among these comets with i = 27 deg separated by more 2002-E18). Although q is still is therefore suggested. [MPEC than five months. M. Meyer was larger, and there are substantial 2002-E18, 2002 March 7] the first to point out the similarity differences in the other orbital between the orbits of C/1997 L2 elements, the L and B values are 1999 P6 (SOHO), 1999 P7 (MPEC 1997-M06, MPC 35205) also similar to those of both comet (SOHO), 1999 P8 (SOHO) & and C/2001 X8 (MPEC 2002- 96P/Machholz 1 and the 1999 P9 (SOHO) These comets B01, MPC 44505), comets with i Quadrantid meteor stream. were discovered by Rainer Kracht = 72 deg separated by 4.5 years; it [MPEC 2002-E25, 2002 March 9] on March 17 (P6) and March 19 also appears that the poorly I pointed out to Brian Marsden in SOHO C2 images. C/1999 P6, observed comet C/2001 E1 can be that members of this group are 1999 P8 and 1999 P9 belong to associated with this pair, if the NEOs and can potentially come the Marsden group, and C/1999 orbit with i = 107 deg on MPEC very close to the Earth post P7 to the Meyer group. 2001-F52 is replaced by the one perihelion. Indeed the published with i = 73 deg on MPC 44505. orbit for 1999 J6 gives a miss R. Kracht points out that, like distance of 0.03 AU, making it the C/1999 N6 (cf. MPEC 2002-F03), 1997 G7 (SOHO) This comet, fourth on the list of comet close C/2001 Q7 (cf. MPEC 2001-R36) discovered by Rainer Kracht on approaches, although the orbit is does not have a unique orbit February 8, is clearly a seventh rather uncertain. solution, an alternative low-i member of the Meyer group (cf. solution being: IAUC 7832), as already suggested 1999 M3 (SOHO) A possible by M. Meyer on Feb. 10 on the member of the Marsden group of T = 2001 Aug. 21.80, q = 0.0445, basis of preliminary comets was discovered by Rainer e = 1.0, Peri = 54.77, Node = measurements. [MPEC 2002-D16, Kracht in archival SOHO imagery 43.95, Incl = 13.28 2002 February 21, IAUC 7841, from 1999 June 30 on 2002 2002 March 4] February 27. He suggests that, with C/1999 M3 and perhaps C/2000 O3, these 1997 H4 (SOHO) & 1997 H5 Marsden group comets comets form part of the extended (SOHO) These comets, 1999 N5 (SOHO) & 1999 N6 Marsden population (i.e., having discovered by Rainer Kracht on (SOHO) The longitudes and the same longitude and latitude of February 11 and 12 in SOHO C2 latitudes of perihelion (deg, perihelion). Indeed, we could say images, appear to be the eighth J2000.0) of the orbits for these that these four comets belong to and ninth members of the Meyer comets, which were discovered by the Kracht group. [MPEC 2002- group (cf. IAUC 7832, MPEC Rainer Kracht in SOHO C2 F43, 2002 March 22] 2002-D16). [MPEC 2002-D41, images on 2002 March 12, are L = 2002 February 27, IAUC 7841, 107.1, B = +12.0 and L = 96.0, B 2002 A4 (SOHO) A Meyer group 2002 March 4] = +10.9, respectively. C/1999 N5 comet discovered in archival C2 is a clear member of the Marsden images from January 1 by Rainer 1999 K16 (SOHO) & 1999 L9 group and C/1999 N6 a likely (SOHO) These comets, member of the more extended 7P/Pons-Winnecke was discovered by Rainer Kracht on population (cf. MPEC 2002-E18, discovered by Jean Louis Pons February 22 and 25 in SOHO C2 2002-E25). Possibly C/1999 N6 is with a 0.12-m refractor at images, are the tenth and eleventh quite closely associated with Marseilles in 1819, but was then members of the Meyer group C/1999 M3 (though not so much lost until rediscovered by [MPEC 2002-E05, 2002 March 1] with C/2000 O3), but the orbit Friedrich August Theodor solution is not unique. [MPEC Winnecke with a 0.11-m refractor 1999 F3 (SOHO) Another Meyer 2002-F03, 2002 March 16] in Bonn in 1858. He group comet, discovered by demonstrated the identity and Rainer Kracht on 2002 April 14 in Kracht group comets recovered the comet in 1869. The C2 images from 1999 March 17. In a communication to the Minor perihelion distance has slowly Planet Center on Mar. 3, R. been increasing since the early 1998 A2 (SOHO), 1998 A3 Kracht suggested that, on the 1800s. It can make close (SOHO) & 2000 B8 (SOHO) basis of the apparent motion, there approaches to the Earth and did so Meyer's discovery C/2000 B8 (in was some loose association in 1927 (0.04 AU), 1939 (0.11), C2 on 2002 March 4) is a member between C/1999 M3 and C/2000 1892 (0.12), 1819 (0.13) and 1921 of the Meyer group. C/1998 A2 O3 (cf. MPEC 2000-Q09), despite (0.14). An outburst of the meteor (discovered in C2 on 2002 March the evident difference in the usual shower associated with the comet, 3) and A3 (discovered in C2 on orbital elements. Nevertheless, it the June Bootids, occurred on 2002 March 8), detected by can be noted that the perihelion 1998 June 27.6. Kracht, are members of the directions are L = 103.9, B = Marsden group, objects that could +11.4 (degrees, J2000.0) for It has proved fainter than expect in fact have orbits differing C/1999 M3 and L = 100.6, B = and no confirmed visual significantly from the assumed +10.8 for C/2000 O3. On Mar. 4, observations have so far been parabolas. Nevertheless, the Kracht wrote that, again despite received. It is a morning object, objects clearly have orbits that differences in the usual orbital and was predicted to reach 11th pass rather close to that of the elements, the perihelion direction magnitude in May after which it is earth (postperihelion), and D. A. for C/2000 O3 is close to the unfavourably placed for J. Seargent has remarked on the average value, L = 102.6, B = observation from the UK. BAA COMET SECTION NEWSLETTER 14 THE COMET'S TALE
Observers at lower latitudes will changes only to the angular be able to follow it until elements. 1964 was another good The comet doesn't reach September. It moves eastwards, return and the comet reached 9m. perihelion until next year, but being in Aquila in April and already a few observers have Aquarius in May. UK observers may follow it until picked it up at between 14th and May, but the comet is likely to be 15th magnitude. The solar 19P/Borrelly appears to have only 15th magnitude. Although it elongation is now decreasing, but peaked in brightness in late continues to brighten, the solar it should remain visible September at around 10th elongation decreases and it is throughout the summer. magnitude according to the light poorly placed when at its brightest curve, however observations by a (11m) at the end of the year. The uncorrected preliminary light couple of observers put it brighter curve from 11 visual and CCD than 9th magnitude. When 29P/Schwassmann-Wachmann observations is m = 4.8 + 5 log d brightest it was a morning object, is an annual comet which has + [15] log r which discouraged observation. frequent outbursts and seems to After perihelion it steadily faded, be more often active than not at 67P/Churyumov-Gerasimenko becoming more diffuse, although the moment, though it rarely gets was discovered in 1969 it initially approached closer to brighter than 12m. It spends the September, by Klim Churyumov the Earth. year in Capricornus reaching and Svetlana Gerasimenko on a opposition in early August, fairly plate taken for 32P/Comas Sola at close to Neptune. The comet is an Alma Ata observatory. It reached ideal target for those equipped its present orbit after a very close with CCDs and it should be encounter (0.05 AU) with Jupiter observed at every opportunity. in 1959, which reduced the Unfortunately opportunities for perihelion distance from 2.74 to UK observers are limited, as its 1.28 AU. At a good apparition, altitude will not exceed 20° from such as in 1982, when it this country. approached the Earth to 0.4 AU and was well observed by the Carl A Wirtanen discovered comet section, it can reach 9m. 46P/Wirtanen at Lick in 1948. It 2002 December 21, Pepe Manteca is in a chaotic orbit, and its The comet is another morning perihelion distance was much object, and even at best it th The uncorrected preliminary light reduced due to approaches to probably won’t exceed 12 curve from 120 observations is m Jupiter in 1972 and 1984. It has magnitude. Southern observers = 6.8 + 5 log d + 18.4 log r been reported to outburst, but may pick it up around the solstice, BAA data suggests that it was just but from the UK we won’t pick it rejuvenated after the perihelion up before August, when it will be distance was reduced. It is a fading. Again the elongation is target for the Rosetta mission. A not good, increasing from around December perihelion would give a 50º to 100º at the end of the year. close approach to the Earth, The comet’s track closely however the present period is parallels that of 46P/Wirtanen, exactly 5.5 years so that perihelia entering Gemini in August and alternate between March and ending the year on the border of September. Leo and Virgo.
The comet is a morning object. 95P/Chiron is an unusual comet More southerly placed observers in that it is also asteroid 2060. It may pick it up in June, but UK reaches 17m when at opposition in observers will probably not find it June in Sagittarius. CCD V until August, when it is fading magnitudes of Chiron would be of from its best magnitude of 11. particular interest as observations 22P/Kopff was discovered The solar elongation only show that its absolute magnitude photographically by A Kopff at increases from around 40º to 60º varies erratically. It was at Konigstuhl Observatory in 1906, by the end of the year, so it is perihelion in 1996 when it was when it was around 11m. The next never very well placed. In June it 8.5 AU from the Sun and will be return was unfavourable, but it is in Cetus, moving into Taurus in nearly 19 AU from the Sun at has been seen at every return July, Gemini in August and Virgo aphelion in around 50 years time. since then. Following an in November. encounter with Jupiter in 1942/43 96P/Machholz The orbit of its period was reduced and the 65P/Gunn was discovered in 96P/Machholz is very unusual, perihelion distance decreased to 1970 after a perturbation by with the smallest perihelion 1.5 AU. The following return was Jupiter in 1965 had reduced the distance of any short period comet one of its best and it reached 8m. perihelion distance from 3.39 to (0.13 AU), which is decreasing The next return was unusual, in 2.44 AU. In 1980 two further with time, a high that it was 3m fainter than prediscovery images were found eccentricity (0.96) and a high predicted until perihelion, when it on Palomar plates taken in 1954. inclination (60°). Studies by brightened by 2m. It suffered The comet can be followed all Sekanina suggest it has only one another encounter with Jupiter in round the orbit as it has a active area, which is situated close 1954, but this made significant relatively low eccentricity of 0.32. to the rotation pole and becomes BAA COMET SECTION NEWSLETTER 2002 April 15 active close to perihelion. The observations. The uncorrected comet may be the parent of the preliminary light curve from 82 Quadrantid meteor shower. It is observations is m = 8.0 + 5 log d rarely sufficiently well placed to + 3.9 log r. see visually and the 2002 return is no exception. However, at perihelion on 2002 January 8 it was only a few degrees from the Sun and was seen in the SOHO LASCO coronagraphs from January 6 to 11. On January 7 it 2001 November 25.91 Giovanni was about 2nd magnitude with a 4 Sostero, Remanzacco Observatory degree tail. It brightened to perhaps -2 just after perihelion on I observed it on October 9 under January 9. relatively poor conditions, using the Northumberland refractor 1999 U4 (Catalina-Skiff) The x230. The comet was surprisingly object is very distant, but the easy to see and I estimated it at extrapolated visual light curve around 12th magnitude. An suggests that it should be visible th observation with the until the autumn, fading from 14 Thorrowgood refractor on magnitude. CCD observations 2000 WM1 (LINEAR) Brian October 23 put the comet at 10.3, suggest that the comet is much Marsden notes on MPEC 2001- th generally diffuse but with a small fainter than this, perhaps 17 U43 [2001 October 23], that 'The star-like condensation. magnitude. The uncorrected "original" and "future" barycentric preliminary light curve from 55 values of 1/a are +0.000500 and - observations is m = 6.9 + 5 log d 0.000266 (+/- 0.000002) AU**-1, + 4.6 log r respectively.' The original value is greater than 10-4, hence the comet is probably not a new arrival from the Oort cloud and has made at least one previous visit to the inner solar system.
2001 December 5, Martin Mobberley
By the end of November 2001 the comet had reached 5th magnitude and was an easy object. It then slowly faded and observations by Southern Hemisphere observers in mid January put the comet at 6th magnitude, about a magnitude fainter than suggested by the preliminary light curve. 2002 February 7, Rolando Ligustri
2001 November 10, Gabriel Oksa
J. Watanabe, National Astronomical Observatory (NAO) of Japan, reports the following antitail lengths and position angles for this comet from I-band CCD images taken by H Fukushima with the NAO 0.50-m f/12 reflector (noting the earth's passage through the orbital plane of the comet on Nov. 20.18 UT): 2002 March 23, Rolando Ligustri
Nov. 16.503, > 8'.5, 283 deg; 2000 SV74 (LINEAR) The 17.542, > 6'.5, 300 deg; 18.526, > Andrew Pearce reported an 7'.9, 302 deg; 19.555, > 6'.2, 317 outburst on 2002 Jan 27.85UT: extrapolated light curve suggests m1=4.6, Dia=3.5', that the comet will slowly fade deg; 22.372, > 4'.7, 1 deg. Small from 13th magnitude. As with scale jet-like structure near the DC=8...20x80B...Andrew Pearce nucleus was also recognized on (Nedlands, Western many comets the visual Australia)[Comet has clearly observations generally put the these images. [IAUC 7762, 2001 November 29] undergone a significant brightness comet as being brighter than CCD increase in the last 24 hours or so. BAA COMET SECTION NEWSLETTER 16 THE COMET'S TALE
Surface brightness of the coma comet on October 14 when it had 2002 April 1, Rolando Ligustri has increased significantly. brightened to 14.2 in his 0.27-m Faintly visible to the naked eye SCT x88. By December it had An apparently asteroidal object even at only 10 deg altitude. Tail brightened to around 12.5. It reported by LONEOS was visible 0.5 deg long in PA 195 moved north, but was not very announced on MPEC 2001-P40 deg. Estimate made in 8x40B at well placed and few Northern last Aug. 13. Numerous observers the same time: m1=4.6, Dia=4', Hemisphere observers reported could not detect any cometary DC=8. I suspected something may observations. The visual light activity, despite the cometlike be up the previous morning but curve is not very well defined, but orbit. Now approaching the observation was hampered can be represented by m = 11.3 + perihelion, the object has finally with the comet only 1' away from 5 log d + [10] log r from 39 shown cometary activity, detected a 6th mag star. Quick examination observations. by several observers as indicated of the comet through a 20cm by the following reported total reflector (90x) revealed an intense magnitudes and coma/tail data central condensation which from CCD images: Jan. 11.44 UT, appeared distinctly non stellar. No 16.1, 0'.4 coma, 0'.5 tail in p.a. evidence of any split, however the 230 deg (A. Nakamura, Kuma, telescope probably lacked the Ehime, Japan, 0.60-m reflector); degree of resolution required to 22.39, 14.7, diffuse (S. Wakuda, confirm this.] Shizuoka, Japan, 0.25-m reflector); Feb. 1.40, 13.5, 0'.9 coma, broad tail toward west with the longest segment being 0'.9 long in p.a. 220 deg (Nakamura); 1.41, 12.8, fan-shaped coma spanning p.a. 200-345 deg (T. Oribe, Saji, Tottori, Japan, 1.03-m 2002 February 24, Sostero et al reflector). Recent astrometry and the orbital elements appear on MPEC 2002-C04. [IAUC 7814, 2002 February 2].
I observed it on February 9.81 and estimated it at 11.3: in the Thorrowgood refractor. The current light curve suggests that it will rapidly fade from around 10th The uncorrected preliminary light magnitude. It also suggests that curve from 715 visual the comet might have been observations is m = 7.1 + 5 log d observable to visual observers a + 10.6 log r, though this makes no month before the first reports allowance for the outburst. It will were made. be visible until August 2002. The uncorrected preliminary light
2001 K5 (LINEAR) The comet is 2001 N2 (LINEAR) may reach curve from 46 visual observations distant and will remain at around 13th magnitude between May and is m = 10.2 + 5 log d + 5.9 log r, 14th mag visually for some time. August. though this is a poor fit. This is LINEARs 64th comet. 2001 OG108 (LONEOS) As the clue of a cometary type orbit suggested, this object did eventually show cometary activity and brightened rapidly
2001 Q4 (NEAT) The latest The uncorrected preliminary light elements give T as 2004 May 16 curve from 11 visual observations with q at 0.96 AU. The value of is m = 4.9 + 5 log d + 7.1 log r 1/a is 0.000043, suggesting that this is a new visitor from the Oort 2001 MD7 (P/LINEAR). cloud. [MPEC 2002-A87] The Michael Mattiazzo observed the comet should be a bright object in BAA COMET SECTION NEWSLETTER 2002 April 17
May 2004. Adopting a perihelion at 1.07 AU at the conservative magnitude law (7.5 2001 TU80 (LINEAR-NEAT) beginning of November. [MPEC log r), suggests a peak of around An 18th mag object independently 2001-W05] 3rd magnitude, whereas the discovered and reported as standard 10 log r gives around 0 nebulous with a 3" coma by 2001 W1 (LINEAR) A 19th mag magnitude. NEAT at Palomar on Nov. 16.53 object reported by LINEAR as UT has been identified by G. V. apparently asteroidal but with 2001 Q6 (NEAT) Initial Williams, Minor Planet Center, unusual motion on November observations suggested that the with an apparently asteroidal 17.43, and thus posted on the comet could reach 14th mag at object reported on Oct. 13.44 and NEO Confirmation Page, has high northern declination in 17 by LINEAR (m_2 = 19.8; been found to appear cometary by October, however it was discovery observations on MPS other observers. CCD images unexpectedly a couple of 39482) and on Oct. 19 by NEAT taken by J. Nomen (Barcelona, magnitudes brighter. This is at Haleakala (MPS 40840), from Spain, 0.40-m f/2 Schmidt NEAT's 15th comet and their 13th which an apparently routine telescope) on Nov. 18.15 UT this year. minor-planet orbit was computed show the object to be slightly (MPEC 2001-V35). Following diffuse (m_1 = 18.0). CCD posting on the NEO Confirmation observations obtained by T. Spahr Page, P. Kusnirak at Ondrejov at the 1.2-m Mount Hopkins found the comet to be moderately reflector on Nov. 18.33 show a condensed with a 0'.3 coma on very diffuse coma of diameter CCD images taken on Nov. 17.2 about 7" and a very faint tail with a 0.65-m f/3.6 reflector. about 15" long in p.a. 200 deg. [IAUC 7753, 2001 November 17] [IAUC 7754, 2001 November 19]. The comet is in a short period The comet will brighten a little. orbit of 7.2 years, with perihelion of 1.94 AU in mid December and 2001 W2 (BATTERS) S. will fade. Nakano, Sumoto, Japan, reports The comet passed within about the discovery of a 14th mag comet 0.1 AU of Jupiter in 1985, prior to on November 21.45 by A. Asami which it was in a more distant, on CCD images taken with the less eccentric orbit. Bisei Spaceguard Center 0.50-m f/2.0 reflector in the course of the 2001 U6 (LINEAR) An "Bisei Asteroid Tracking apparently asteroidal object of Telescope for Rapid Survey" 19th mag discovered on Oct. program. Additional observations 29.40 by LINEAR, posted on the were reported following posting NEO Confirmation Page due to its on the NEO Confirmation Page. unusual motion, has been found to [IAUC 7758, 2001 November 21] be cometary by J. Ticha and M. A. Hale, Cloudcroft, NM, reports Tichy (Klet, diffuse with "a slight that this comet showed a 0'.8 coma" on Nov. 3.8 UT) and by R. coma and total visual magnitude Trentman (Louisburg, KS, Nov. 12.7 on Nov. 22.09 UT (0.41-m 6.3). [IAUC 7746, 2001 reflector). Additional astrometry November 6] The comet is distant and preliminary parabolic orbital and will reach perihelion in elements appear on MPEC 2001- August 2002. It will not come W53. [IAUC 7760, 2001 within visual range. November 23] The comet reached Brian Marsden notes on MPEC perihelion in late December, at 2002-C55 that the "original" and 1.05 AU, but did not become "future" barycentric values of 1/a much brighter than at discovery. are +0.001080 and +0.001158 (+/- The latest elements show that it is The uncorrected preliminary light 0.000051) AU**-1, respectively. in a Halley type orbit with period curve from 44 visual observations This suggests that it is not a new 76 years. is m = 5.5 + 5 log d + 41.0 log r, comet from the Oort cloud. but again this is a poor fit. The comet was never well placed A/2001 UU92 (NEAT) is an for observation, but a few A/2001 SS107 (LINEAR) is an asteroid, of 19th magnitude, observers reported it at around asteroid discovered by LINEAR discovered by NEAT on October 11th magnitude in December. on September 20, which has a 19.32. With a period of 5.63 perihelion distance of 1.51 AU years, the orbit is typical of a A/2001 WS1 (LINEAR) is an and a period of 5.46 years in a Jupiter family comet. It will be at asteroid, of 17th magnitude, typical Jupiter family comet orbit. perihelion at 1.05 AU at the end discovered by LINEAR on Perihelion was on 2002 March of December. [MPEC 2001-W34] November 17.07. With a period 9.4. of 4.92 years, the orbit is typical A/2001 VJ75 (LINEAR) is an of a Jupiter family comet. It was 2001 T5 (SOHO) A non Kreutz asteroid, of 20th magnitude, at perihelion at 1.03 AU in late comet discovered by XingMing discovered by LINEAR on October. [MPEC 2001-W36] Zhou on October 17 in C3 images November 12.45. With a period of from October 14. [IAUC 7750, 5.20 years, the orbit is typical of a A/2001 WU1=1979 WN8 2001 November 10] Jupiter family comet. It was at (Palomar-LINEAR) is an BAA COMET SECTION NEWSLETTER 18 THE COMET'S TALE asteroid, of 18th magnitude, re- 2001 X2 (P/Scotti) J. V. Scotti, 2001 X8 (SOHO) A non Kreutz discovered by LINEAR on Lunar and Planetary Laboratory, comet discovered by Alexander November 18.22 and originally reports his discovery of a 19th Mimeev on December 12 in real- found at Palomar on 1979 mag comet on CCD images taken time C2 images. [IAUC 7797, November 24. With a period of with the 0.9-m Spacewatch 2002 January 19] Studies by Maik 5.56 years, the orbit is typical of a telescope on December 14.44, Meyer show that it forms a triplet Jupiter family comet. It will noting a coma diameter of 5" and with 1997 L2 and 2001 E1. reach perihelion at 1.35 AU in a tail 0'.40 long in p.a. 283 deg early June 2002. [MPEC 2001- (and m_2 = 22.7). Confirming A/2001 XQ (LINEAR) is an W38] observations were made at Klet asteroid, of 15th magnitude, by J. Ticha, M. Tichy, and P. discovered by LINEAR on 2001 WF2 (P/LONEOS) An Jelinek, who reported a 8" coma December 6.16. It was at apparently asteroidal object of and a faint westward tail. [IAUC perihelion at 1.04 AU in mid 19th magnitude discovered by 7775, 2001 December 14]. The December. [MPEC 2001-X24] LONEOS on November 17.27 latest orbit shows that the comet is With a period of 6.87 years, the and designated 2001 WF_2 (cf. of short period (7.3 years), with orbit is typical of a Jupiter family MPEC 2001-W42) was found to perihelion at 2.5 AU in 2001 comet. It approached to 0.53 AU have a well-defined 45" tail in p.a. October. It will fade. of Jupiter in 1983, which made 320 deg on CCD images obtained small changes to the orbit. on Feb. 13.5 UT by T. B. Spahr 2001 X3 (11P/Tempel-Swift- with the 1.2-m reflector at Mount LINEAR) R. Huber, Lincoln A/2001 XU (NEAT) is an Hopkins. Following notification Laboratory, Massachusetts asteroid, of 18th magnitude, by Spahr, C. W. Hergenrother Institute of Technology, reports discovered by NEAT on also found a 27" tail in p.a. 320 that a 20th mag object discovered December 7.45. With a period of deg and a stellar central by LINEAR on Dec. 7.08 was 4.93 years, the orbit is typical of a condensation on a 1500-s co- found to be diffuse on Dec. 17 Jupiter family comet. It will added R-band image taken with (with prediscovery LINEAR data reach perihelion at 0.41 AU in the Catalina 1.54-m reflector. back to Sept. 10). G. Hug, early February. It is a PHA, [IAUC 7827, 2002 February 13] Eskridge, KS, reports that the possibly coming as close as 0.005 The object was at perihelion in object is probably diffuse on CCD AU, but on this occasion only gets late January at 0.98 AU and has a images taken on Dec. 19.1 UT to within 0.22 AU. [MPEC 2001- period of 5.0 years. It is (red mag 17.2-17.8). [IAUC 7778, X28] intrinsically very faint and will 2001 December 19] The comet fade. has a period of 6.4 years, with A/2001 XL16 (Spacewatch) is an perihelion at 1.6 AU. It will fade. asteroid, of 21st magnitude, 2001 X1 (LINEAR) R. Huber, discovered by Spacewatch on Lincoln Laboratory, C. Hergenrother, Lunar and December 10.13. With a period Massachusetts Institute of Planetary Laboratory; and K. of 5.73 years, the orbit is typical Technology, reports the discovery Muraoka, Kochi, Japan, suggested of a Jupiter family comet. It will by LINEAR of a comet on images a link between comet 11D (last reach perihelion at 1.50 AU in taken on Dec. 13.44 that show a seen in 1908) and P/2001 X3 (cf. mid January. [MPEC 2001-Y44] bright core surrounded by a IAUC 7778) - a linkage diffuse coma (comet's magnitude confirmed at the Minor Planet 2001 Y1 (152P/Helin-Lawrence) given as 16.5-17.0) and exhibiting Center and by S. Nakano This periodic comet, first a tail at least 95" long in p.a. 295 (Sumoto, Japan). The orbital observed in 1993, has been deg. CCD observations on Dec. elements by Nakano (from 43 recovered by T Oribe at the Saji 14.1 UT by R. Stoss and P. observations, 1908-2001, have observatory. It will reach Geffert (Starkenburg Sternwarte, mean residual 0".8; perihelion at the end of 2002. 0.45-m f/4.4 reflector) reveal a nongravitational parameters A_1 On 2001 Dec. 25, S. Nakano well- condensed coma with a thin = +0.13 +/- 0.01, A_2 = -0.0134 (Sumoto, Japan) reported that T. tail 5' long in p.a. 300 deg (m_2 = +/- 0.0007). The comet was not Oribe had apparently recovered 16.5). CCD images taken in found in 1963 despite a prediction comet P/1993 K2 (= 1993 XI = twilight and poor seeing by A. C. by B. G. Marsden (IAUC 1838, 1993l) the night before Gilmore (Mount John, 1.0-m f/7.7 1839, 1840). More recent (December 24.86) with the 1.0-m reflector) on Dec. 14.6 show the predictions were made by reflector at the Saji Observatory. object as diffuse (m_1 = 14.6- Marsden and Sekanina (1971, A.J. The position was within 2" of the 15.1) with a broad, faint fan tail 1' 76, 1142), by Nakano (Comet prediction by B. G. Marsden on long in p.a. about 315 deg. [IAUC Handbooks for 1989, 1995, and MPC 34423 (ephemeris on MPC 7774, 2001 December 14]. The 1996, Oriental Astronomical 43696). No information was comet was around 15th magnitude Association; and NK 686), and by provided about the object's visually. Brian Marsden notes on Muraoka (Comet Handbook for appearance other than m_1 = MPEC 2002-F19 [2002 March 2001, OAA). The indicated 19.5. The comet has now been 18] that the "original" and correction to Nakano's 2001 independently reported by K. "future" barycentric values of 1/a prediction (1998, NK 686) is Sarneczky and Z. Heiner in 2002 are +0.02285 and +0.001659 (+/- Delta(T) = +3.4 days. [IAUC Jan. 11 data obtained with the 0.6- 0.000042) AU**-1, respectively. 7779, 2001 December 20] The m Schmidt at Piszkesteto, at m_1 These values show that the comet comet was listed amongst those = 20, but again with no is not a new one from the Oort due to return in my predictions for information about the appearance. cloud. 2001 in the BAA Journal for These observations confirm a December 2000. tentative single-night detection by C. W. Hergenrother and D. Means BAA COMET SECTION NEWSLETTER 2002 April 19 of an object of stellar appearance observations by R. H. McNaught (in an 840-s co-added exposure) with the 1.0-m reflector at Siding A/2002 AR4 (LINEAR) is an at the comet's expected position a Spring on Jan. 11.6 showed that asteroid, of 20th magnitude, year ago with the Steward the first object, now designated discovered by LINEAR on Observatory's 2.3-m reflector at C/2002 A1, was slightly diffuse January 8.23. It will reach Kitt Peak. [IAUC 7790, 2002 with a very faint 25" tail in p.a. perihelion at 1.13 AU in mid January 14] 260 deg, and that the second March. [MPEC 2002-A51] With object, C/2002 A2, was almost a period of 5.17 years, the orbit is Further to IAUC 7790, K. stellar with a very narrow 20" tail typical of a Jupiter family comet. Sarneczky reports that his 300-s in p.a. 250 deg. The respective It has made no recent close unfiltered CCD images taken on discovery observations and orbital approaches to Jupiter. Jan. 11.2 UT show a diffuse, 8" elements are given in MPEC coma and a faint, narrow, 13" tail 2002-A62 (which also contains all A/2002 AO7 (LINEAR) is an in p.a. 283 deg. [IAUC 7792, the relevant astrometry and asteroid, of 20th magnitude, 2002 January 15] Further to ephemerides). The 2001 Dec. 13 discovered by LINEAR on IAUC 7790, T. Oribe reports that and 17 observations of C/2002 A1 January 8.16. It will reach his CCD images taken on 2001 originally appeared on MPS perihelion at 1.10 AU in early Dec. 24.86 UT show a 0'.15 coma 45271 under the designation 2001 April. [MPEC 2002-A63] With a and an 8" tail in p.a. 295 deg. XG_115. The minimum distances period of 5.10 years, the orbit is [IAUC 7794, 2002 January 17] from Jupiter were ><0.4 AU typical of a Jupiter family comet. around 2001 July 9 and 18 for It has made no recent close 2001 YX127 (P/LINEAR) An C/2002 A1 and C/2002 A2, approaches to Jupiter. object previously reported as respectively. [IAUC 7788, 2002 asteroidal by LINEAR has been January 11] The latest orbits, on A/2002 AF29 (NEAT) is an shown to have cometary MPEC 2002-C58 and C69, gives asteroid, of 20th magnitude, characteristics. It is distant and them a periodic orbit of around 77 discovered by NEAT on January faint, and will fade from 20th years, with perihelion distance of 13.41. It will reach perihelion at magnitude. 4.7 AU in early December 2001. 1.25 AU at the end of January. An apparently asteroidal object of [MPEC 2002-A94] With a period 20th mag discovered by LINEAR 2002 A3 (LINEAR) An 18th of 5.97 years, the orbit is typical on December 17.32 and mag object reported as asteroidal of a Jupiter family comet. It has designated 2001 YX_127 (cf. by LINEAR on January 13.23 has made no recent close approaches MPS 47220, MPO 24028) has been noted by several CCD to Jupiter. been found to have a broad, fan- observers to be cometary: Jan. shaped extension in p.a. 100 deg 19.9 UT, slightly diffuse, m_1 = A/2002 AO148 (LINEAR) is an on CCD images obtained on Feb. 17.3 (J. Nomen, Barcelona, asteroid, of 20th magnitude, 14.2 UT by T. B. Spahr with the Spain); 20.6, 10" coma, m_1 = discovered by LINEAR on 1.2-m reflector at Mount Hopkins. 17.3 (J. Broughton, Reedy Creek, January 11.36. It is in a 13.5 year Co-added CCD R-band images Qld.); 21.2, fuzzy coma of orbit, with perihelion at 4.1 AU taken at about the same time by C. diameter about 10" (R. Dyvig, and an eccentricity of 0.27. W. Hergenrother with the Quinn, SD); 21.2, m_1 = 17.0, [MPEC 2002-C107] Catalina 1.54-m reflector show a 22" tail in p.a. 250 deg (R. 7" coma and a broad tail 8" long Fredrick, R. Trentman, and R. 2002 B1 (LINEAR) An 18th mag in p.a. 100 deg. [IAUC 7828, Gruenke, Louisburg, KS). [IAUC object reported as asteroidal in 2002 February 14] 7799, 2002 January 21] It has a appearance by LINEAR on perihelion distance of 5 AU and January 26.09, and posted on the 2002 A1 (LINEAR) and 2002 reaching perihelion in May. It will NEO Confirmation Page, has A2 (LINEAR) Two 19th mag fade. been found to be cometary on objects of asteroidal appearance CCD images taken by M. Tichy separated by <1 degree and 2002 AR2 (P/LINEAR) An and J. Ticha at Klet (coma having similar, somewhat unusual asteroid discovered by LINEAR diameter 7"-8", on Jan. 29.8 and motion were reported by LINEAR on January 6.15 has been found to Feb. 1.8 UT; coma diameter 9" on Jan. 8.32. Further observations be a comet, initially suggested by with m_1 = 17.7-18.0 and a faint were made following placement its orbit, with follow up tail in p.a. 165 deg on Feb. 4.8) of the objects on the NEO observations showing a coma. and by A. Galad and L. Kornos at Confirmation Page, and The object is in a 12.5 year orbit, Modra ('slightly diffuse' on Feb. 1 prediscovery observations in with perihelion at 2.0 AU in mid and 2). [IAUC 7817, 2002 Nov.-Dec. 2001 were identified at January. It will fade from 18th February 4] It is intrinsically faint the Minor Planet Center in magnitude. and will fade from 17th mag. The LINEAR and NEAT data. Orbit latest orbit (MPEC 2002-C70 computations for the two objects A/2002 AZ1 (Spacewatch) is an gives it a periodic orbit, with gave very similar results asteroid, of 21st magnitude, period around 31 years. (basically differing only in T) and discovered by Spacewatch on showed that the objects were only January 7.27. It will reach 2002 B2 (LINEAR) An 0.7 AU from Jupiter at discovery. perihelion at 0.67 AU in late apparently asteroidal 19th mag Observations by T. B. Spahr and March. [MPEC 2002-A31] With object reported by LINEAR on P. Berlind with the 1.2-m reflector a period of 4.86 years, the orbit is January 23.40 and posted on the at the F. L. Whipple Observatory typical of a Jupiter family comet. NEO Confirmation Page has been on 2002 Jan. 11.4 UT showed that It passed 0.72 AU from Jupiter in found to be cometary by M. Tichy the objects had faint, narrow tails 1999, though this did not and J. Ticha at Klet (coma around p.a. 250 deg. Independent significantly affect the orbit. diameter 6", with m1 = 17.2, and BAA COMET SECTION NEWSLETTER 20 THE COMET'S TALE faint 9" tail in p.a. 90 deg on Feb. discovery); 2.081, 9.5:, 3' (A. 3.05 UT) and by R. H. McNaught Hale, Cloudcroft, NM, 0.41-m at Siding Spring (8" coma and 10" reflector; thin clouds); 2.43, 8.8, tail in p.a. 60 deg on Feb. 6.66). about 4' (K. Yoshimoto, [IAUC 7821, 2002 February 6] It Yamaguchi, Japan, 20x100 was quite distant and near peak binoculars); 2.47, 8.8, 3' (D. brightness and will fade from 17th Zhang, Kaifeng, Henan, China, mag. 0.20-m f/4.4 reflector, 28x, as used for the discovery on Feb. 2002 B3 (LINEAR) F. Shelly, 1.47; comet more condensed than Lincoln Laboratory, on previous day); 2.53, 9.1, 3' (A. Massachusetts Institute of Pearce, Nedlands, W. Australia, 2002 April 1, Nigel Bryant Technology, reports that an 0.2-m reflector); 2.53, 8.5, 5' (N. apparently asteroidal object of Brown, Quinns Rocks, W. King Charles II was crowned in 19th mag, discovered by LINEAR Australia, 0.15-m refractor). 1660 and had created the Royal on Jan. 26.12 (and placed on the [IAUC 7813, 2002 February 2] Society in the same year. In 1661, NEO Confirmation Page) was Isaac Newton was 18, and went found to show a clear tail in p.a. Nakano, Muraoka and Sato note up to Cambridge in June of that about 330 deg on Feb. 11.09 UT. that there is a possibility that the year. It is unlikely that he T. B. Spahr, Harvard-Smithsonian comet is identical with comet observed the comet as his Center for Astrophysics, reports 1532 R1. Brian Marsden notes on notebook suggest that the first that CCD images taken with the MPEC 2002-C111 : A parabolic comet that he observed was the 1.2-m reflector at Mt. Hopkins on orbit no longer adequately fits the one of December 1664. Halley Feb. 12.13 show the object to be observations, and a revolution would have been too young to very faintly diffuse with a faint period of 400-500 years is likely. record the comet (he was 5), but extension in p.a. 315 deg. [IAUC There is a possibility that the later he computed an orbit similar 7826, 2002 February 12] It is very comet is identical with C/1532 to that of the 1532 comet and distant and near peak brightness R1, as first suggested by S. suggested a possible link. Charles and will fade from 19th mag. Nakano on the basis of Messier noted this possible link, observations through Feb. 10.4. but that it had been refuted by Mechain. 2002 C1 (Ikeya-Zhang) Kaoru Further observations render this Ikeya and Daqing Zhang possibility unlikely, but make it discovered a 9th magnitude comet more probable that the comet is a on February 1. It reached return of comet 1661 C1. Brian perihelion on March 18 at 0.5 AU Marsden notes on MPEC 2002- and brightened to 3rd magnitude. D36 [2002 February 26] : Kaoru Ikeya discovered 5 comets Numerical integration backward in the 1960s, including the of the perturbed equivalent of the spectacular sungrazer Ikeya-Seki above unperturbed orbit solution (1965 S1). yields a previous perihelion date in March 1659. This suggests a Drawing of the 1661 comet (right) Word has been received of the likely identity with C/1661 C1, by Hevelius taken from Guillemin, independent visual discovery of a rather than with C/1532 R1 (cf. 'The world of comets', 1877 comet by Kaoru Ikeya (Mori, MPEC 2002-C111). If this Shuchi, Shizuoka, Japan; 0.25-m identity is confirmed it will be the The comet was observed and reflector, 39x; communicated by longest period comet so far drawn by Hevelius. The optical S. Nakano, Sumoto, Japan; coma known to return. quality of his telescope was far diameter 2' with weak inferior to those of today and the condensation; motion about 5' A new orbit is given on MPEC features drawn may be imaginary. northeastward in 30 min) and by 2002-F21 [2002 March 18] and The comet was thought to be a Daqing Zhang (near Kaifeng, Brian Marsden notes that the portent for 'Black Bartholomew's Henan province, China; 0.2-m orbital elements yield the year of Day' when 900 non-conformist reflector; communicated by J. the previous perihelion passage as clergymen were ejected from their Zhu, Peking University; coma T = 1660.9 +/- 0.4 (1 sigma), in benefices following the Act of diameter 3'). very close agreement with the Uniformity of 1662. Succeeding bright comets were associated 2002 UT R.A. (2000) Decl. m1 Observer with the Plague and the Fire of Feb. 1.408 0 08.9 -17 42 9.0 Ikeya London. The comet was Feb. 1.47 0 09 -17 30 8.5 Zhang illustrated by Johann Gabriel [IAUC 7812, 2002 February 1] Doppelmayr in 1742.
value T = 1661.1 for comet The following excerpt about Precise astrometry (Feb. 1-2) and C/1661 C1. [See also Nakano's C/1661 C1 is from volume 1 of the preliminary parabolic orbital orbit, which links C/1661 C1 with Cometography by Gary Kronk: elements given below appear on C/2002 C1 and Kenji Muraoka 's MPEC 2002-C03. Visual m_1 and orbit (in Japanese). coma-diameter estimates: Feb. 1.910 UT, 7.5:, 5' (P. M. Raymundo, Salvador, Brazil, 0.25-m reflector; independent BAA COMET SECTION NEWSLETTER 2002 April 21
9th. By the 10th Welper said the until Nevil Maskelyne (1786) tail was basically extending looked into the matter. Maskelyne perpendicular to the horizon, took the elapsed time between the although he noted a slight tilt perihelion date of these two toward the west. Welper's comets, added it to the 1661 observation of February 11 was perihelion date, and predicted the his last, because of an extended comet would arrive at perihelion period of bad weather. around 1789 April 27. He added that assumed perturbations by In volume 46 of Travels and Jupiter would probably cause the Explorations of the Jesuit perihelion date to occur earlier, Missionaries in New France possibly as soon as late 1788. (1899), Jerome Lalemant With an assumed perihelion date (superior of the Jesuit missions in of 1789 January 1, he computed New France, now Canada) wrote an ephemeris for the period of of this comet. He said, "the comet 1788 April 23 to 1789 January 1. 2002 February 3.75, Giovanni which was visible here, from the Maskelyne said the comet could Sostero end of January to the beginning of be recovered as early as 1788 March, was soon followed by the September by observers near the Discovered: 1661 February 3.2 disasters of which those stars of equator or south of it, and added, (D=0.62 AU, r=0.48 AU, evil omen are the forerunners." In "The Cape of Good Hope would Elong.=23 deg.) Last seen: 1661 describing its appearance, he said, be an excellent situation for this March 28.1 (D=0.99 AU, r=1.39 "Its tail, extending westward, purpose." Early in 1788, both AU, Elong.=88 deg.) Closest to pointed toward us and seemed to Johann Elert Bode and Capel the Earth: 1661 January 29 threaten us with a flagellation, of Lofft made similar predictions for (0.6062 AU) Calculated path: which it was, to us, a brilliant but the probable return of this comet. DEL (Disc), AQL (Feb. 6), SER fatal portent." He continued, "it However, despite the preparation (Mar. 26) did indeed move from West to and numerous searches, the comet East, following the flight of the was not found. constellation of the Eagle, at whose head it appeared, although Full moon: February 14, March by another movement it tended a 15 Sources: J. Hevelius (1668), p. little Northward from us." 483; Marie de l'Incarnation (1671), pp. 263-4; E. Halley, Marie de l'Incarnation (1671), Philosophical Transactions of the superior of the convent at Quebec, Royal Society of London, 24 Canada, wrote a letter to her son (1705), pp. 1882-99; A. G. Pingré, in 1661 September which also Cometographie (1784), p. 10; P. described this comet. She said, "A F. A. Méchain, Memoirs of the comet was seen, its rods pointed Pres. of Paris (1785), p. 395; 2002 March 29, David Strange toward the earth. It appeared at Philosophical Transactions of the about two or three o'clock in the Royal Society of London, 76 The Polish astronomer Johannes morning and disappeared toward (1786), pp. 426-31; N. Hevelius (1668) provided the six or seven with the day. In the Maskelyne, Gentleman's most extensive set of observations air was seen a man of fire, Magazine, 57 (1787), p. 59; of this comet. He discovered it on enveloped in fire. A canoe of fire Berliner Astronomisches Jahrbuch 1661 February 3.2, shortly after was also seen and, towards (1788), pp. 195-6; C. Lofft, morning twilight had begun. Montreal, a great crown likewise Gentleman's Magazine, 58 (1788), Computations using the orbit of fire." pp. 1048-50; Berliner below indicate the comet was then Astronomisches Jahrbuch (1790), exiting the twilight after having Edmond Halley (1705) and P. F. pp. 184-6; The London and passed only 17 degrees from the A. Mechain (1785) computed Edinburgh Philosophical sun on January 28. Within a few very similar parabolic orbits, with Magazine and Journal of Science days Hevelius estimated the tail the former noting a similarity to (Series 3), 7 (1835 Jul.), p. 37; length as 6 degrees and noted the the orbit of the comet of 1532. Travels and Explorations of the comet appeared fainter than Alpha Mechain's orbit is given below. It Jesuit Missionaries in New Aquilae. Hevelius noted a indicates the comet reached a France, Volume 46, edited by multiple structure of the nucleus maximum declination of +6 Reuben Gold Thwaites, on several occasions up to degrees (apparent) on February Cleveland: The Burrows Brothers February 20. The comet was last 14. The orbits are as follows: Company (1899), p. 205; S. K. detected on March 28.1 by Hevelius. Computer T AOP AN (2000.0) i q e The observations of Eberhard Halley 1661 Jan. 27.4868 (UT) 33.552 87.169 32.596 0.448510 1.0 Welper (Strasbourg, France) were Mechain 1661 Jan. 27.381 (UT) 33.450 86.562 33.015 0.442722 1.0 included in the 1788 volume of the Berliner Astronomisches Jahrbuch. Welper first saw the Vsekhsvyatskij, Physical comet on February 8 and said the Characteristics of Comets (1964), tail extended 5 degrees and was Despite Halley's suggestion that p. 50; Journal of the Royal perpendicular to the horizon. He C/1532 R1 and C/1661 C1 might Astronomical of Canada, 70 noted the same orientation on the be related, the idea was ignored (1976 Dec.), pp. 311-12. BAA COMET SECTION NEWSLETTER 22 THE COMET'S TALE
25th day in the first month of the with a coma diameter of 4'. The Graeme Waddington provides the first yaer of the Genkei reign- comet was also easily visible in following information on orbital period a 'guest star' appeared to 14x100 and 20x80 binoculars. computations: the west of the (Tung-) Pi (14th Observations on February 11 lunar mansion)."(Dainihonshi ch. suggest a magnitude of about 7. Nakano has a new linked solution 359; K; Hsi.) Ho Peng Yoke Maciej Reszelski reports that the forcing the identification of (1962)'s 'Ancient and Mediaeval comet had reached 6.5 in 20x60B C/2002 C1 (Ikeya-Zhang) with Observations of Comets and on February 15.72. On February C/1661 C1 (Hevelius). Nakano Novae in Chinese Sources' p 176. 26.76 I observed the comet in specifies the elements at epochs in Time is about 18:00?('Tori-no- rather bright twilight with 20x80B 2002 and 1661. Integrating the koku'). and estimated it at 5.9, with a 9' 2002 set back to 1661 gives a ion tail in pa 85. It was distinctly difference of 0.12 days in the time The comet of 5th February, 1273 brighter on February 28.78 when I of perihelion passage when has a record in Japan. "On the made it 5.6 with a 0.5 degree tail compare to Nakano's 1661 set. 16th day in the first month of the in pa 65. tenth yaer of the Bun-ei reign- Integrating both sets backwards period [5th February, 1273] a gives an estimate of the likely (hui) comet was 2002 March 6, Michael Jager uncertainites involved and we now get the sequence
1661 Jan 28.9 (+- 0.1 d) 1273 Apr 25 (+- 1.5 d) 879 Jan 10 (+- 15 d) 426 May (+- 500 d)
Integrations of Nakano's previous linked solution also gave a perihelion in 1273 Apr/May and Muraoka gave 1273 Mar 26 for his integration of Nakano's previous solution. [My own rough integration of Nakano's orbit suggested previous returns around 1273 May, 879 January and 425. Gary Kronk's Cometography lists a comet for 877, but not 879]. seen....."(Dainihonshi ch. 359; K.). Ho (1962) p194. The By the end of February the comet Ho Penk Yoke gives as #439 in observation on 11th April was a had reached naked eye brightness his catalogue a comet of bluish- 'guest star' and is not this comet. and a steady stream of reports white colour and with the (Sato) began to arrive. The comet had appearance of loose cotton that become very well condensed, appeared in 1273 April. The with an almost stellar nucleus. At details given (movement through its brightest in late March, images Auriga towards U.Maj) mimic the show that the coma was distinctly expected appearance of the green. From dark sky sites, the integrated object for 1273 - the comet showed a prominent tail, agreement can be improved by with a maximum length reported having a periheilon passage ~ 20- by visual observers of around 6 30 days earlier than my degrees. integrations give (i.e. around 1273 April 1, near to Muraoka's result).
Thus is seems to me likely that the 1273 April comet mentioned in the Oriental annals can be equated with Ikeya-Zhang (2002) = Hevelius (1661) and as such 2002 March 11.77, Tony Scarmato could be used refine the long-term integration uncertainties. Early observations suggested that it was brightening quite rapidly. The comet of 1273 April is also On February 5.77 I estimated it at listed by Hasegawa (1980) and 7.7 in the 20cm Thorrowgood appears on page 223 of Gary refractor x40, however other Kronk's Cometography. observers made it a little fainter on the same evening. On February Hirohisa Sato provides the 9.77 I made it 8.1 in the same following information: instrument x70, though this time 357 observations received other observers were indicating a February 2 - April 13 give a The comet of 11th February, 877 brighter magnitude. The coma preliminary light curve of m = 7.1 has a record in Japan. "On the was well condensed, DC5 - 6, + 5 log d + 10.6 log r BAA COMET SECTION NEWSLETTER 2002 April 23
Occasionally, I would boost the At 3:40 on Monday morning, he Stop press: The latest orbit for magnification up to 212x to look happened across "a little gray 2002 C1 on MPEC 2002-H23, at a particular object, but not for smudge" nestled in the Aquila which includes non-gravitational sweeping the skies. This was a Constellation. He did some quick parameters gives the perihelion deliberate search, although I am research using a sky atlas and time for the last return as relatively new at comet searching. numerous databases, but couldn't 1667.9±0.3. I had spent only about 70 hours locate any references to his find. up to the time of the finding. A 2002 C2 (LINEAR) R. Huber real lucky find! I have been deep Trying not to get his hopes too and F. Shelley, Lincoln sky observing for about 20 years. high, Snyder checked the comet's Laboratory, Massachusetts location again. "The comet had Institute of Technology, report the Not that I'm too much of a moved a bit, but not too much, discovery by LINEAR of an 18th believer in the psychic side of and I found it again fairly easily. mag comet on February 1.09 with things, but my wife and I had Dawn was coming, and my view a tail 42"-47" long in p.a. 12.5 gone out to dinner with another of the comet was fading, but by deg. Cometary activity has been couple very involved in amateur now I was becoming more sure of confirmed via CCD observations astronomy and we ate at a my discovery," Snyder said. by A. Galad and L. Kornos at Chinese restaurant (this was on Modra on Feb. 1.8 (m_1 = 16.3, Sunday evening, the evening He immediately e-mailed news of asymmetric coma extending 15" before the discovery). After the his discovery to the Central toward p.a. about 30 deg) and 2.7 meal, we received our fortune Bureau for Astronomical UT (slightly diffuse with coma cookies. Mine read "You will Telegrams, the Harvard-affiliated diameter about 10"), by J. Ticha soon be the center of attention". clearinghouse for new and M. Tichy at Klet on Feb. 2.7 On every other occasion where I discoveries. It was 4 a.m. and the (coma diameter 10"), and by T. get one of these fortunes, I just world was being told the latest Payer at Duesseldorf, Germany, toss it away. Well, on this space find had been made at a on Feb. 2.8 (coma visible, m_1 = particular evening, I stuck it in my small observatory in Southeastern 16.6). [IAUC 7815, 2002 shirt pocket and took it home with Arizona. February 2] It is a distant object me. Well, I stayted up the entire and will fade. night and it was 8 hours later that Several anxious hours later, he I came across the comet. Now, for received a reply. CBAT has spent 2002 CW134 (P/LINEAR) A the time being, I guess I've been at the interim time researching his 20th magnitude object, discovered the center of attention! My wife find, verifying Snyder's by LINEAR on February 7.47 has wants to frame it - but gee, its experience and credentials, and been found to have a coma. It was only 70 x 13 mm! locating the comet. CBAT asked near perihelion at 1.84 AU and for additional information, which has a period of 6.8 years. Snyder provided, and then he waited. A/2002 CE10 (LINEAR) This asteroid discovered by LINEAR is "It's been a whirlwind couple of in a retrograde cometary type days," Snyder said. "But orbit with period of 25 years. It is yesterday (Tuesday), they finally still some 16 months from let me know that I had really perihelion at 1.9 AU in June 2003, discovered a new comet." so it may begin to show cometary activity in the future. Discovered Visual observers have put the on February 6.32 at around 20th comet at around magnitude 11 magnitude it is still 4.8 AU from over the last month, with a 2' the Sun. [MPEC 2002-C83, 2002 diameter, diffuse coma. February 13] 26 observations received March 2002 E2 (Snyder-Murakami) A 13 - April 7 give a preliminary new comet has been discovered light curve of m = 8.0 + 5 log d + by US astronomer Douglas 2002 April 17, Pepe Manteca [10] log r Snyder and Japanese astronomer Shigeki Murakami. The comet is Stargazer finds comet by Lyn 2002 F1 (Utsunomiya) Syogo about 11th magnitude and moving Southerland Sierra Vista Herald Utsunomiya from Japan has northwards. It is just past March 14, 2002 discovered another comet. The perihelion and will slowly fade object is diffuse, with a weak from around 11th magnitude. Palominas - With his eyes on the condensation and visible in the There is some similarity (pointed skies and the strains of "Some morning twilight. Images show a out by "Mitch") between the Enchanted Evening" playing in tail up to 90' long. The comet orbital elements and those of the background, Doug Snyder reached perihelion in April and C/1998 H1 (Stonehouse). made the discovery of a lifetime will fade thereafter, though the early Monday morning. solar elongation remains poor. Doug Snyder has provided the following information to the The amateur stargazer discovered comet mail list: I was using a a new comet streaking through the magnification of 149x, which was Aquila Constellation in the heart providing me with a field of 32' of the Summer Milky Way on my 20" f/5 Obsession. galaxy.
BAA COMET SECTION NEWSLETTER 24 THE COMET'S TALE
see two naked eye comets at the One of the PCs had a faulty same time. mother board, and whilst this had been replaced, I left the movie 33 observations received March loop running and checked it 21 - April 18 give a preliminary intermittently to see if there were light curve of m = 10.6 + 5 log d further problems. On April 12 I + 17.0 log r had checked the SOHO recent discoveries page from my office A/2002 FC (LONEOS) is an PC and seen no new reports, but asteroid, of 19th magnitude, didn't immediately check the discovered by LONEOS on latest images. After coffee I went Syogo Utsunomiya March 16.24. It will reach to look at the loops on the test PC perihelion at 0.96 AU at the end and immediately spotted the new of May. [MPEC 2002-F14] With object, which I reported to Doug a period of 4.85 years, the orbit is Biesecker, but discovered that typical of a Jupiter family comet. XingMing Zhou had reported it It is a potentially hazardous first. Subsequently I've found that asteroid, and can pass 0.022 AU Internet Explorer works better from the Earth. than Netscape on my office Kracht on April 8. computer as well, so if you want to search for SOHO comets using 2002 G1 (SOHO) A non the real-time images I would sungrazing group comet recommend using this browser. discovered in real-time C2 images by Rainer Kracht on April 2. It A/2002 GJ8 (NEAT) is an remains at small elongation from asteroid, of 19th magnitude, the sun and is not expected to be discovered by NEAT on April 2002 March 23.15, Giovanni detected from the ground. 12.41. It will reach perihelion at 0.51 AU at the end of June. Sostero 2002 G3 (SOHO) XingMing [MPEC 2002-G62] With a period Zhou discovered a moderately of 4.45 years, the orbit is typical bright comet on C3 frames on of a Jupiter family comet. April 12.4, with Jonathan Shanklin making an independent A/2002 GO9 (NEAT) is an discovery shortly afterwards. The asteroid, of 20th magnitude, bright, slow moving, object discovered by NEAT on April appeared at the bottom of the 12.34. It reached perihelion at frames beginning at around 00:00 10.45 AU (just outside the orbit of on April 12 and was moving up Saturn) at the end of December and to the left. It had no obvious 1996. [MPEC 2002-H03] With a tail, and was brightening quite period of 399 years and aphelion rapidly. At its brightest, just at 98 AU, the orbit is typical of a before perihelion, it reached long period comet. around 1st magnitude, and although it grew a short tail, I have begun to compile an began a dramatic fade, turning archive of all the images that I into a ghostly blur, last seen receive and you can find this on The comet was highly condensed around April 19.0. Although the Section web pages. This and showed a short tail when I potentially observable from the includes all the images included observed it on April 6.14 and ground in late April, it seems very here, at far better resolution. 7.15. The observations up to unlikely that the object will be When submitting images please April 9 suggested that it was only recovered. use the naming format that you brightening slowly and would see there as this makes it easy to reach mag 7 when brightest. I made the independent discovery catalogue the images. Nicolas Biver, observing on April of the comet whilst at work. I had 10.16 noted a significant been configuring a number of For the latest information on brightening, with the comet at computers with the Windows discoveries and the brightness of magnitude 5.9, with a nearly 2000 operating system and used comets see the Section www stellar appearance, suggesting a the SOHO real time images to test page: recent outburst. The following the Internet connection and http://www.ast.cam.ac.uk/~jds or morning he reported that the memory. In the process I the CBAT headlines page at comet had brightened further, but discovered that Microsoft Internet http://cfa- had become more diffuse and Explorer seemed to give much www.harvard.edu/cfa/ps/Headline showed jets. I was able to better views of the SOHO real- s.html observe it in brightening skies on time movies than did Netscape April 13.16 and estimated it at 5.6 4.7, which was my preferred web Produced by Jonathan Shanklin in 20x80B. A further observation browser. Initially I put this down E&OE in misty conditions on April 14.15 to the limited amount of software put the comet at 3.9. Several running on the new machines and observers in better skies were able the fact that they were higher to observe it and 2002 C1 with the performance than my office PC. naked eye, a rare opportunity to BAA COMET SECTION NEWSLETTER