A total of 259 IAU Circulars were issued in 2002, up from the 229 published in 2001. The most common topics covered were supernovae (whose discoveries appeared on 54 percent of the Circulars, while at least one separately titled follow-up item on a supernova appeared on 46 percent of the year's IAUCs). Follow-up items involving novae and other unusual Galactic variable stars appeared on about a quarter of the year's Circulars. Comets continued in 2002 to have a standard presence in the CBAT publications (with non-spacecraft discoveries and recoveries appearing on 18 percent, SOHO discoveries on 17 percent, and follow-up information on comets appearing on a fifth of the 2002 Circulars). Eleven percent of the year's Circulars contained items on high-energy (TeV, gamma-ray, and x-ray) transients, and four percent contained reports on radio transients. Over a dozen IAUCs during the year covered the discoveries and follow-up information for numerous satellites of both major and minor planets. Twelve new satellites of Jupiter and one of Uranus were announced in 2002.
There were 292 new extragalactic supernova discoveries made in 2002 that were reported on IAUCs that year (nearly fifty more than the record number that were announced the previous year). Also, 47 supernovae discovered prior to 2002 were designated and announced on Circulars in 2002. Some 158 supernovae announced during the year were fainter than mag 20 at discovery (roughly double the number for 2001), meaing that there were notably fewer discoveries of brighter supernovae. Spectroscopic observations (usually with a supernova type given) were reported on the year's IAUCs for more than 90 percent of supernova discoveries brighter than mag 20 -- though for objects fainter than mag 20, spectroscopic typing dropped to around 40 percent (and 86 percent of apparent supernovae of mag 23 or fainter had no available spectroscopic information). There is thus some continuing question about the value of designating most objects fainter than mag 23 that cannot be confirmed as supernovae. The brightest supernova of the year was the peculiar type-Ic SN 2002ap in M74, peaking at visual mag about 12 in early February, and numerous items reporting x-ray, optical, infrared, and radio observations appeared on the Circulars. SN 2002fk in NGC 1309 reached visual mag about 13 in September; a half dozen other supernovae peaked around mag 14-14.5 in 2002.
Some fifteen IAUCs carried discoveries of novae and outbursts of recurrent novae or novalike variables during 2002. A peculiar binary variable discovered at visual mag 10 by N. J. Brown in January, designated V838 Mon, was announced on the Circulars, where its spectroscopic development and expanding light echo and shell were documented in some detail. In addition to V838 Mon, five novae were assigned permanent variable-star designations on IAUCs in 2002, in the continuing collaboration between the CBAT and IAU Commission 27 (via N. N. Samus). The brightest of these novae, V4743 Sgr, peaked near fifth magnitude in mid-September. An outburst (to mag 8) of the nova IM Nor was announced in January, its first since 1920.
In addition to the scores of new SOHO comets announced and designated during the year, some four dozen non-SOHO comets received new 2002 designations, including three recoveries and one rediscovery (C/2002 C1 = 153P/Ikeya-Zhang, which reached third magnitude in late March, being the first return of a comet observed by Hevelius in 1661). Comet 54P was found again after having been missed since 1965. Besides the visual discovery by Ikeya and Zhang, four other comets were discovered visually by amateur astronomers in 2002 and announced by the Bureau. In June, a Circular announced seven winners of the 2002 Edgar Wilson Award for amateur comet discoveries. Comet C/2000 WM_1 reached m_1 about 2.5 in late January 2002. Some Circulars during the year were devoted to the discovery of some 19 companions to comet 57P.
The number of paid subscribers to the printed edition of the IAU Circulars continued to fall, from 216 at the end of 2001 to 193 at the end of 2002. In addition, there were 38 free (complimentary or exchange) subscriptions to the printed IAUCs at the end of 2002. The printed IAUCs go to 77 addresses within North America and 154 outside of North America. There were 470 paid subscribers to the CBAT/MPC electronic service at the end of 2002, compared with 501 at the end of 2001.
A new feature implemented in December was the introduction of the Central Bureau Electronic Telegrams, or CBETs. The CBETs are e-mailed items intended for later publication on IAUCs, set up mainly to aid in the quick dissemination of urgent information when the Director is unavailable, so that others assisting in the running of the CBAT are freed from the additional effort needed to produce the TeX version of the Circulars. As in recent years, most of the Circulars in 2002 were prepared by the undersigned, with very helpful editorial backup by Director Emeritus B. G. Marsden (who prepared numerous Circulars during the year and helped to proofread and critique most of the rest prior to issuance). Minor Planet Center Associate Director Gareth Williams also helps to maintain the Bureau's presence on the World Wide Web. At SAO, Muazzez Lohmiller has continued to handle the accounts, addressing of envelopes, and other administrative matters; Judy Terry has also handled numerous CBAT administrative matters. Dan Wooldridge continues, as he has for years, with the fine printing of the IAUC cards.
Daniel W. E. Green
Director of the Bureau
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