Electronic Telegram No. 439 Central Bureau for Astronomical Telegrams INTERNATIONAL ASTRONOMICAL UNION M.S. 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A. IAUSUBS@CFA.HARVARD.EDU or FAX 617-495-7231 (subscriptions) CBAT@CFA.HARVARD.EDU (science) URL http://cfa-www.harvard.edu/iau/cbat.html COMET 73P/SCHWASSMANN_WACHMANN The components H, J and L, mentioned on IAUC 8685 on Mar. 8, were reobserved by P. Birtwhistle, Great Shefford, Berkshire, England, on Mar. 23.1 UT and by E. J. Christensen, Mount Lemmon Survey, on Mar. 23.5. The magnitudes were given as 18.9, 19.9 and 21.0, respectively, by Birtwhistle, who adds that component H had a coma of diameter 9" and a tail 40" long in p.a. 255 deg, that component J had a coma of diameter 9" and a tail 20" long in p.a. 230 deg, and that component L had a very diffuse coma of diameter 5" and a possible tail 15" long in p.a. 245 deg. Neither observer recorded component K, but both observers independently reported two new components, designated M and N, estimated by Birtwhistle at mag 20.8 and 21.4, respectively, the former having a diameter of no more than 4" and no tail, and the latter having a stellar head and a faint tail 70" (possibly up to 90") long in p.a. 255 deg. The astrometric observations are provided on MPEC 2006-F22. The new components M and N are in the vicinity of component H and, using the earlier orbit (MPEC 2006-B27) for component B with perihelion time adjusted as before, they correspond to T = 2006 June 8.28 and 8.30 TT, respectively, although component N lies perhaps 40 arcsec north of the line of variation. NOTE: These 'Central Bureau Electronic Telegrams' are sometimes superseded by text appearing later in the printed IAU Circulars. (C) Copyright 2006 CBAT 2006 March 23 (CBET 439) Brian G. Marsden