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    Re: Planet positions and light travel time
    From: Antoine Couëtte
    Date: 2017 Dec 19, 05:19 -0800

    Re : Hirose-dec-2017-g40942

    From Africa this time,

    Thank you Paul for your excellent explanations about geometric, astrometric and apparent places.

    I looked into this in detail over 30 years ago, and to the best of my memory the highest values for light-time corrections occur for the Planets who show the highest speeds relative to the Earth.

    Frank lately quoted an aberration value - i.e. a "overall" light time effect - close to 0.3' for Mars.

    Venus aberration can reach higher values than Mars aberration. And,

    Mercury aberration can reacher high values than Venus. I think that Mercury aberration reaches or even exceeds 1.0' under some [extreme] cases.

    I just need to dig out some actual examples of aberration values from my archive files when I return home and publish them here.

    Unless of course one of you gives us such examples meanwhile ... and if so, many thanks in adavance !


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