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Edgar Edgar is offline
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First recorded activity by BoatBanter: Jul 2006
Posts: 741
Default Seen Sailing South Saturday


"Gilligan" wrote in message
...
As we sailed south is seemed as the bottom of the lighthouse was taller
than the top.


This is a gravitational lensing phenomena as predicted by Einstein. The

cold
air is denser and has more gravity so light travels slower through it. The
image of the bottom of the light house travelled through colder air so the
image took longer to get to you than the top image. Since you were

traveling
toward the light house it was getting bigger with time and the delayed

image
is shorter because when that image was initially propagated you were

further
from the light house. Hence the bottom of the light house appears smaller.
The phenomena is known as transient specular image gradient delay.



Joe's boat must have an impressive turn of speed...