TJM obs of 2004 Apr 24 and 27 UTC

From: Ted Molczan (
Date: Tue Apr 27 2004 - 07:04:20 EDT

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    11732 80 019D   2701 G 20040424083901040 17 25 1445522+135033 37 S
    11732 80 019D   2701 G 20040424083904290 17 25 1446494+145132 37 S
    11732 80 019D   2701 G 20040427081030900 17 25 1342157+173745 38 S
    11732 80 019D   2701 G 20040427081101760 17 25 1345683+271439 57 S
    11732 80 019D   2701 G 20040427081136110 17 25 1350225+393601 28 S
    Site 2701: 43.68764 N, 79.39243 W, 230 m
    The object was 5.3 s late on Apr 24 and 6.7 s late on Apr 27, and about 0.2 deg
    off track, relative month-old elements:
    1 11732U 80019D   04082.79613209 0.00000250  00000-0  10538-3 0    03
    2 11732  63.4100 314.2532 0686000 344.4059  15.5940 13.42292265    09
    I had not been able to identify the reference stars of my Apr 24 observations
    because I foolishly failed to time the object's passage relative my intercept
    reference stars. I seldom stop to sketch reference stars, relying on ObsReduce
    to display them correctly, based upon the latest elset. This method works
    beautifully - as long as ObsReduce knows how early or late the satellite was. 
    My standard operating procedure is to plan to intercept satellites near a good
    pair of reference stars. Since I know their location, I am almost guaranteed one
    accurate point, which also enables ObsReduce to determine how early or late the
    object was, so that it can show me the reference stars of any subsequent points.
    This method enables me to easily observe a large number of points per pass, as I
    discuss in the ObsReduce manual:
    Variable Stars
    The second reference star of my final point this morning is variable star R
    Canum Venaticorum (R CVn), located at 13:48:57.0435 +39:32:33.1910 (2000.0). Its
    magnitude ranges between 6.5 and 12.9 over a period of 328.53 days. Currently it
    is about mag 7.9
    ObsReduce was no help finding this star, because it plots it as mag 9.8. Perhaps
    it would be worth using a different symbol to plot large-amplitude variables,
    and to display their max and min magnitude. More useful would be to display
    their predicted magnitude at the time of the observation, based on their light
    Perhaps I will add this feature at the same time I add asteroids and the planets
    to the display.
    I also plan to produce a larger star data base for observers using large
    telescopes and/or CCD cameras, which I will provide free on CD-ROM to those with
    a proven need.
    Ted Molczan
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