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    Fata Morgan images set me thinking
    From: Mark Coady
    Date: 2017 Apr 17, 18:35 -0700

    Back after an unplanned and frustrating hiatus, a promotion and taking over an engineering department shorthanded and very behind. Boat was in exile too on a different dock so my weekend internet was off while they dredged my harbor. Finally getting back into place this week

     I snapped the attached off the TV screen while watching outrageous acts of science a while back.   A sailboat looking like its well above the horizon.  I understand temperature inversions are a culprit often enough. I gather in the past whole islands were reported that did not exist due to peculiar atmospheric abberations.

    It sent me to wondering...  

    1) How far off is the horizon in this situation, with respect to measured altitude.

    2) If it is off, does the haze and funny appearnace always tip you off to be cautious.  (some part of the crappy pic is I shot it watching a TV set, there are better examples on google images I am sure).

    3) If there is no ship, but such a conditon exisits,  how bad might your sextant reading be off if you didn't pick up on signs from the appearance.

    In other words..how much does the horizon position get distorted in this situation.

    I have observed quite a few odd atmoshpheric conditons at sea over many years on the water; mostly when you could see them with respect to references by being in sight of land or floating objects.  Other than heat waves, can you see it all by yourself in open ocean? 

    Are there other conditions that might produce waka-waka sextant readings, that may sneak up on us.



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