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    Re: Jupiter and Mars
    From: Bill Ritchie
    Date: 2024 Aug 9, 10:39 -0700

    I used Astron’s inter-body arc facility, which gives the minimum geocentric separation at 14:53:15 UT and a distance of 0° 18.3862′, or 0° 18′ 23.175″. It lists the distance at the input time, so I needed to spend about 3 minutes doing a poor man’s binary search (guessing and halving) to find the start and end times of when the minimum remained unchanged, then taking their mean. (Constant 18.3862′ between 14:52:15 and 14:54:15).

    Here is a summary of contributions to date, converted to UT and DM.m format. I have added python / Skyfield's values too. Obviously Astron cannot compete with the 'big boys', but is still well within observable limits. 

     

    UT

    Geocentric Separation

    Antoine

    14:53:21

    0° 18.4′

    SOLEX

    14:53:09

    0° 18.3870′

    Roger

    14:53:09

    0° 18.388′

    Frank

    14:53:10

    0° 18.38862′

    Antoine 2

    14:53:10

    0° 18.392′

    IMCCE

    14:53:09

    0° 18.3867′

    Paul

    14:53:09

    0° 18.3870′

    Astron

    14:53:15

    0° 18.3862′

    Skyfield

    14:53:08.5

    0° 18.38721259′

    I included the arc facility to possibly help with sextant calibration, listing the sextant arc between stars, or between selected limbs of nearer bodies. The geocentric option was added later.

    Bill

       
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