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    Re: Silicon Sea: Leg 72 -NEW
    From: Michael Wescott
    Date: 2001 May 29, 10:08 EDT

    Sam Chan wrote:
    > For unknown body #1, the compass bearing was 349.7.
    > Using Can Dead Man Vote Twice At Election, correcting from
    > compass to true requires easterly variation and deviation be added to
    > compass. The variation was 10dW and deviation was 1dE, totaling 9dW.
    > With a compass bearing of 349.7 and subtracting 9d (since it is W)
    > results in 340.7. There is nothing near that location in the sky.
    >
    > I noticed that if I added instead of subtracting the compass corrections,
    > the location fits Polaris and Deneb, thus my initial question to you to
    > check the compass bearing. I figured that you started off with true
    > bearings and converted them to compass.
    > On 26 May 2001, at 13:43, Michael Wescott wrote:
    > > > > 6)  What are the names of the two unknown bodies?
    > > > > --  ---------------------------------------------
    > > >
    > > > Unknown #1:
    > > >
    > > > 349.7 + 10 - 1 = 358.7d
    > > >
    > > > almost due north and altitude is about same as our latitude:
    > > > got to be Polaris
    > >
    > > Right
    > >
    > > > Unknown #2:
    > > >
    > > > 327.3 + 10 - 1 = 336.3
    > > >
    > > > This is visually in the angle between Polaris to the north and Vega
    > > > to the northwest.  GHA Aries is about 34d and Long is 67W so zenith
    > > > has SHA of about 33d. Looking at the starchart in the almanac, there
    > > > is only one navigational star between Vega and Polaris: Deneb
    > >
    > > Right
    Hmmm. Good point. I just *knew* what the first one was, so I didn't think
    too hard about the calculations. Two wrongs made it right :-)
    <PRE>
    --
            Mike Wescott
            Wescott_Mike{at}XXX.XXX
    </PRE>
    

       
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