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Reports from Geisei Observatory <April 7, 2009>


C/2009 F4 (McNaught), C/2009 F5 (McNaught), C/2009 F6 (Yi-SWAN), and C/2006 W3 (Christensen)

    C/2009 F6 (Yi-SWAN) was observed visually by the 15cm refractor at 22x. It was very faint and its total magnitude was estimated to be at 11.5 with the coma 1.5' in diameter. The photograph below was taken with the 70cm reflector, but the comet's low altitude and poor seeing made it difficult to focus. The GSC catalog does not provide adequate data around the position of the comet. In the ACRS catalog several comparison stars are found some distance away from the comet. Because of this, the results below may contain some inaccuracy. The comet can be observed visually by a 20cm telescope or larger.
    Nearby C/2006 W3 was also visually observable.


C/2009 F6 (Yi-SWAN)
10-minute exposure from 4:30 J.S.T. on April 7, 2009
70cm f/7 reflector, TMY 400 film



C/2006 W3 (Christensen)
7-minute exposure from 4:10 J.S.T. on April 3, 2009
70cm f/7 reflector, TMY 400 film


    CK09F050   2009 04 02.72014 14 57 46.70 -31 44 23.3          17.5 N      372
    CK09F050   2009 04 02.73576 14 57 45.42 -31 43 58.7                      372
    CK09F050   2009 04 06.76389 14 51 52.50 -29 58 48.3          17.5 N      372

    CK09F040   2009 04 06.75556 15 41 26.20 -23 48 11.6          18.0 N      372

    CK09F060   2009 04 06.80416 23 59 04.98 +54 54 32.3          12.5 N      372
Copyright (C) 2009 Tsutomu Seki.