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    Re: Was it a "super moon" or just the same old moon?
    From: Fred Hebard
    Date: 2015 Sep 28, 11:14 -0400
    There is usually some vertical shrinkage of the moon at the horizon due to refraction, but if you measure the semi-diameter horizontally, it is usually the same as when the moon is high in the sky.  The larger apparent diameter when the sun and moon are near the horizon is a neuro-optical trick your eyes play on you when there are nearby objects with which to compare the diameter, as opposed to when the sun or moon are high in the sky.

    The moon varies in semi-diameter from its high of 16.7 arcminutes last night to a low of 14.7, as its distance from the earth varies.  The variation occurs over the course of a month, but isn’t coincident with the moon’s phases; the moon will have a semi-diameter of 14.7 on October 10.  There also is variation over the course of the year in the monthly maximum and minimum semi-diameter of the moon; compared to September, in April the maximum was 16.5 arcminutes and the minimum 14.8.

    Full eclipses of the moon are spectacular.  I don’t know whether or not the semi-diameter at the time of eclipse contributes to the spectacularity.  That is an interesting question for the group.  I suspect the coincidence of very high maximum semi-diameter with a full eclipse, which only occurs at a full moon, was more an opportunity for NASA to blow its horn than an event of scientific interest.  (I believe is right and proper for NASA to so blow its horn, by the way).

    Fred

    Fred Hebard



    On Sep 28, 2015, at 10:37 AM, Rommel John Miller <NoReply_Miller@fer3.com> wrote:

    Don’t get me wrong, what I saw last night was spectacular, except for the intermittent clouds that disturbed the view in Hebron, MD. 

     

    I am color blind and maybe this is where the disorder affects me most in the subtle differences and shifts in color in stars, planets and natural satellites. 

     

    Commonly I am red/green blind,  but it might go deeper, and what I saw in the moon last night was maybe 2% growth and very intense shifts in greys as the satellite emerged from earth’s shadow. 

     

    Granted on the horizon and just rising the moon here was larger than normal, but I attribute that to the atmospheric distortion at the horizon.  I’d saw there that the moon was 5% larger in appearance. 

     

    No one discusses the idea of light diffraction on this list and I find it essential to understanding near earth objects as well as deep space ones.  As water in a bubble will magnify that which is behind it, so too does the fluid atmosphere tend to distort and make things to appear larger to our eyes here on earth.  I do believe that this is what Michelangelo was talking about in his notebooks on the subject of super moons as opposed to the moon we see at zenith. 

     

    And even at zenith, we on earth are not in the vacuum of space, so distortion happens there too but not as severe as near the base of the horizon.  Why?  Light air rises and heavy air sinks. 

     

    Heavy air contributes to severe diffraction and even colorization.  And I have seen blood red moons in my day, at least what I believe to be red. 

     

    Thing is it was rather spectacular but just the same old moon here in Hebron, MD USA. 

     

    Rommel John Miller

    8679 Island Pointe Drive

    Hebron, MD  21830-1093

     

    410-219-2690 (Land and Home)

    443-365-7925 (Cell)

     

    rommeljohnmiller---.com

    rommeljmiller{at}outlook.com

     

     

    From: NavList@fer3.com [mailto:NavList@fer3.com] On Behalf Of Geoffrey Kolbe
    Sent: Monday, September 28, 2015 4:12 AM
    To: rommeljohnmiller---.com
    Subject: [NavList] Re: Was it a "super moon" or just the same old moon?

     

    Here in Scotland (the Borders in the South of Scotland) the sky was brilliantly clear. The moon at totality was definitely red! A dark red rather than a blood red, to be true, but it was a 'red moon'!

     

    Geoffrey Kolbe


    Dr Geoffrey Kolbe, Riccarton Farm, Newcastleton, Scotland, TD9 0SN

    Tel: 013873 76715

    Mob: 0773 8069 663

     

    On Mon, Sep 28, 2015 at 4:57 AM, Rommel John Miller <NoReply_Miller@fer3.com> wrote:

    Okay, we are just emerging from totality at 10:23 pm local Hebron, MD time. 

     

    No blood red moon, nothing but the same old silver colored disk that when it is full is termed “moon bright.”

     

    What all the fuss over these myths of super moons is about when any physicist in the field of Astronomy could tell you, it just isn’t true. 

     

    But I guess some ship board sailors and navigators out there still put faith in St. Elmo and his strange “fire.” 

     

    Oh well, I always thought science would dispel myth, not perpetuate them. 

     

    But Barnum was right, one is born every minute. 

     

    Rommel John Miller

    8679 Island Pointe Drive

    Hebron, MD  21830-1093

     

    410-219-2690 (Land and Home)

    443-365-7925 (Cell)

     

    rommeljohnmiller---.com

    rommeljmiller{at}outlook.com

     

     

     


       
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