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    Re: Bright Venus again
    From: Bill Ritchie
    Date: 2018 Nov 26, 11:05 +0000
    Nice problem, Kermit. l modified Astron to show more decimal digits in the geocentric arc utility, which then gave a theoretical answer of  01° 14.711191' at 19:59:40 UT. That is  01° 14' 42.67", just on your 4" margin. With a more realistic 3 decimal places set, there was no change from 01° 14.711'  between 19:43:58 and 20:15:22. Astron uses the same data as Peter's spreadsheets, so the agreement is expected.

    Bill Ritchie. 50N 03W

    On Sat, Nov 17, 2018 at 9:17 AM Antoine Couëtte <NoReply_Couette@fer3.com> wrote:

    Bright Venus again
    From: Antoine Couëtte
    Date: 2018 Nov 13, 23:43 -0800

    Lady Venus back to morning skies !

    This morning (Nov 14th, 2018, by 06:15 GMT) it was dazzingly bright seen from home ! Next to another rather Bright Body.

    Question 1 - An easy one : name of the Bright Body next to Venus (i.e. within 1.5°) ?   Spica (Alpha Virginis)

    Question 2 : More difficult : Which day and at what time time (UT or even TT) will the geocentric angular distance between Venus Center and the Bright Body center be minimum ?  Nov. 14th, 2018 by 20h10m TT *** (or by 20h09m UT), i.e. just a few hours after the time this post was published.

    Question 3 : What will be the geocentric angular distance between them, then ? 1°14.8' ****

    Enjoy !


    COMMENT: Interesting exercise since Venus earlier closed up from Spica without catching or overtaking this Star. In other words Venus "stopped short" of Spica at a distance of slightly over 1° as earlier indicated. The distance between them has kept increasing afterwards.

    Such environment (Venus earlier heading "dead on" onto Spica but "stopping short" of this star) is [much] more difficult to accurately compute than if Venus had simply "overtaken" Spica.

    *** 20h10m23.7s TT with an uncertainty of a few minutes of time (maybe up to 10 or even15 minutes of time ?) given the Bodies apparent geocentric configuration,

    **** and a Body Center to Body Center geocentric distance of 1°14'46.9" (+/- 4")

    Antbody to comment and/or to confirm these results ?


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