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    Re: 18 june 2013 lunar distance
    From: Frank Reed
    Date: 2013 Jun 30, 22:52 -0700

    Hi Dave, you wrote:
    "Frank- True LD: 106° 34.4'(GMT)"

    Well, the actual value from my web-based app is 106° 34.443'.

    And you wrote:
    "Paul- geocentric separation angle: 106°34.47′ center to center"

    Yes, I agree. That's nearly 2 seconds of arc difference. Insignificant for anything remotely practical, yet still a somewhat bigger difference than it should be. I'm not sure if the cause is the bad luck of round-off in a specific case or something more interesting. Since I'm prepping for a lunars class in two weeks, it happens that I am FINALLY taking a relevant little software project commercial. So we'll see...

    You added:
    "(dT=67.08)"

    Unless someone makes a huge error in this number (and why would that ever happen in modern ephemerides?), there is no reason to worry about delta-T values. As I have said to Antoine more than once, this is NO concern. Don't go OCD! Resist the urge to "geek-out" for the wrong reasons...

    -FER


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