THE ASTRONOMER Electronic Circular No 209 1988 Oct 16 10.40UT. Telecom Gold 72:MAG60138 Ed:Guy M Hurst, 16, Westminster Close, Kempshott Rise, Basingstoke, Hants, RG22 4PP, England. Telephone:(0256)471074.Int:+44256471074 Telex:265871(MONREF G) Quote"72:MAG60138 ATT G.HURST"in FIRST line. ------------------------------------------------------------------- COMET 1843 I Rob McNaught relays an informal message received from Brian Marsden concerning the recent 'SMM' comets: Comet 1988m, the biggest and brightest of the sungrazers found during the past twelve months could not be seen after perihelion. I wonder, however, whether the perihelic disintegration might still produce a phenomenon like comet 1887 I, "the headless wonder", which was evidently a synchrone, observed for ten days a week or two past perihelion, produced at the comet's demise. If so, Schmidt observations using the following ephemeris might possibly show something (magnitude not guaranteed, of course). Actually, I suspect that all those of the past year (and the space people say there were not as many during preceding years) are related to the immediate progenitor of comet 1843 I, which produced what became comet 1843 I, probably also 1887 I, and a lump of originally mutually-bound orbiting comets with a period a century or so longer that eventually separated (because of the small relative nongravitational forces) to produce the comets of the past year. Is there perhaps also a really big one in there, one that would be bright enough to be seen far from perihelion (before and afterwards) and that might therefore be coming during the next year or so? I gave a perennial search ephemeris for these things in my paper in A.J. Nov. 1967. So far as I know, the only use it got was to enable Jack Bennett to discover his superb nonsungrazing comet 1970 II. It seems to me that it would be useful to conduct an Uppsala Schmidt search now in particular, if only in the hope that there could be comparison with future SMM observations to give some upper limit on the brightness of future Kreutz sungrazers some weeks before perihelion. Ephemeris: 1843 I Date ET R. A. (1950) Decl. Delta r Elong. Phase V 1988 08 27 07 53.12 -03 20.9 2.039 1.411 39.3 27.0 13.0 1988 09 01 08 05.47 -03 51.6 1988 09 06 08 19.49 -04 27.8 1.760 1.199 41.0 33.5 12.0 1988 09 11 08 35.73 -05 10.3 1988 09 16 08 55.05 -05 59.6 1.474 0.965 40.6 42.6 10.7 1988 09 21 09 18.70 -06 55.6 1988 09 26 09 48.68 -07 56.6 1.195 0.699 35.7 56.9 8.8 1988 10 01 10 28.08 -08 55.9 1988 10 06 11 21.74 -09 32.8 0.975 0.366 21.3 83.2 5.6 1988 10 11 12 39.51 -08 37.4 1988 10 16 12 25.98 -11 00.5 1.065 0.262 14.1 68.0 4.3 1988 10 21 12 00.07 -14 38.4 1988 10 26 11 41.31 -17 47.4 1.116 0.627 34.0 62.3 8.2 1988 10 31 11 25.36 -20 41.8 1988 11 05 11 10.46 -23 26.7 1.141 0.905 49.6 56.6 9.9 1988 11 10 10 55.58 -26 04.1 1988 11 15 10 40.05 -28 33.9 1.153 1.144 64.1 51.0 10.9 1988 11 20 10 23.35 -30 54.3 1988 11 25 10 05.17 -33 02.6 1.162 1.361 78.1 45.2 11.7 1988 11 30 09 45.31 -34 54.8 1988 12 05 09 23.81 -36 26.1 1.182 1.562 91.8 39.1 12.3 1988 12 10 09 00.94 -37 31.8 1988 12 15 08 37.22 -38 08.1 1.225 1.751 104.3 33.0 12.9 1988 12 20 08 13.41 -38 13.2 1988 12 25 07 50.31 -37 47.7 1.301 1.930 114.6 27.6 13.4 V503 CYGNI In response to the note on E207, G.M.Hurst reports that he observed the field on 1988 Oct 10.89UT. At the original position of the variable no star was seen to magnitude 15.2v. At the alternative position 'a' a star was seen and estimated at 14.8v. Observations are continuing to try and confirm which is the UG star. Prime focus photographs would also be welcomed. TA INDEX We welcome the following to our group: Anders Lindquist, Stockholm, Sweden. MAG90959 R.P.Jenner, Yate, Avon. MAG90969 Guy M Hurst