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    Re: A little space navigation
    From: Brad Morris
    Date: 2018 Oct 7, 00:48 -0400
    The orb of the Earth is illuminated, therefore we are between the orbit of the Earth and that of Venus.  The Earth is illuminated over the almost all of the orb, or thereabouts, so the Sun is just about directly behind us.

    From our apparent location over the Earth, we are above the ecliptic.  The southern most latitude in Texas is 25.8°.  This is in conflict with the first paragraph.  The maximum declination of the sun is 23.45 degrees.  It cannot illuminate the orb completely if the sun isn't behind us.

    There isn't a star field visible behind the Earth in the image, so we cannot resolve our position along the Earth's orbit around the sun.  

    We cannot tell our altitude without knowing the magnification of the lens that was used to take the photo.  

    Brad



    On Sat, Oct 6, 2018, 1:49 PM David Pike <NoReply_DavidPike@navlist.net> wrote:

    The relative size of the Miami to San Francisco segment clearly increases as you approach the Earth.  Please see the three photos below taken during our recent re-entry.  Assuming we were on the extended plane of the great circle joining San Francisco to Miami roughly half way between the two cities, I calculate in the fourth photograph that Frank took his photo when we were about 2700km above the earth’s surface.  DaveP

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