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    Re: Jupiter and the Moon
    From: Hewitt Schlereth
    Date: 2013 Jan 22, 17:51 -0800

    Hanno, in 2010 at sea in the Caribbean with a group of students sharing a Mk 
    15, by the fifth day they were consistently getting within 2 NM of the GPS.  
    One guy was consistently nailing 1 NM. Much better than the professor, I 
    might add.  :-)
    Once in the mid '70s in the Gulf Stream, I noticed sun and moon on opposite 
    bearings (didn't know about lunar's then, Frank). With an EBBCO plastic 
    sextant, the parallel LOPs were 5 NM apart. (Amazingly, we still found 
    Bermuda!  :-)
    Sent from my iPad
    On Jan 21, 2013, at 5:50 PM, "Hanno Ix"  wrote:
    > Frank:
    > What do you think is the average error of a hooby-navigator on sea?
    > I know there is a wide range, but please give me a range if you can.
    > h
    > ________________________________
    > From: Frank Reed 
    > To: hannoix---net 
    > Sent: Monday, January 21, 2013 1:54 PM
    > Subject: [NavList 22048] Re: Jupiter and the Moon
    > ________________________________
    > Paul, you wrote:
    > "I’d love to know if I missed something. Then I can stop blaming the Davis..."
    > With a Davis plastic sextant, you can reasonably expect errors on the order 
    of +/-2 minutes of arc for lunars. You MAY be able to do somewaht better, but 
    it will take some care. In any case, it is what it. There are different 
    capabilities for different instruments. There's no way that a plastic sextant 
    with a 3x scope can achieve the same accuracy as a high-quality metal sextant 
    with a 7x scope.
    > As for the clearing of the lunar, the process you've described sounds a bit 
    "fishy" to me. You're doing something that 'resembles' the process of 
    clearing a lunar but it's not right. May I suggest that you try out the 
    lunars CLEARING calculator on my web page here: 
    > I have highlighted the word "clearing" here because you do not need the 
    predicted lunars page which you may have assumed was the same thing. You 
    don't need to do any interpolation. There are no issues of interpolation for 
    shorter distances. 
    > After you have tested out some lunars using the clearing tool on my web 
    site, if you would like to experiment more with doing your own clearing, I 
    outlined a quick "calculator" method back in 2004 (good lord, eight years 
    ago!) here:
    > http://reednavigation.com/lunars/easylun.html
    > -FER
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