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    Re: Seeing Moon rising an setting ?
    From: Jeremy C
    Date: 2010 Feb 18, 14:49 EST
    Seeing the actual limb on the horizon at sea is quite a bit more rare than observing the sun rise or set.  this is what makes taking amplitudes of the moon very difficult.  This being said, I have done seen the moon rise twice in the last three years.  The most recent was this summer when I took a moonrise amplitude observation.  The sky and horizon were incredibly clear with no "amplitude clouds." or any other clouds for that matter.  My height of eye was about 30 meters if that is low enough.
    In a message dated 2/18/2010 12:17:27 P.M. Eastern Standard Time, marcel.e.tschudin@gmail.com writes:
    The thread on "An assumption about the moon" reminded me on an other
    question related with the moon which I have in my mind already for
    quite some time: Is it actually possible for an observer at low
    altitudes to see a moonrise or moonset at the apparent horizon ?

    Rough estimations which I made some years ago suggested that the
    extinction by the mass of atmosphere would be so high that this
    shouldn't be possible. The estimation suggested that around 1°
    altitude the extinction would be greater than the brightness of the
    moon. I saw this supposedly confirmed when watching moonsets over the
    Marmara-Sea here in the Istanbul area where the (full) moon just
    dimmed out when approaching the horizon. I am however not sure whether
    this was only due to a "dirty" atmosphere (haze/smog). The Internet
    provides some photos of the moon at landscape horizons but there the
    altitude of that landscape horizon is not known. There are also photos
    from the heavily flattened moon which astronauts took from space
    through parts of the atmosphere. However in those photos the light of
    the moon is likely not to pass the densest lowest part of the
    atmosphere which there is probably only a very thin stripe over the
    earth surface. Do some of you who are occasionally at sea remember
    having actually been able to clearly see a moonrise or moonset at the
    sea horizon?


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