Two high tides
Name: Paul Dickerson
It makes sense to me why there is a high tide at or about noon during new
Moon, but why is there a high tide at or about midnight as well?
The reason is very simple, though it takes a bit of thinking to hit the
right direction. Consider the Earth-Moon system, and visualize Earth as a
sphere with a layer of water all around it. The water closer to the Moon
will get attracted more than the Earth giving rise to the noon tide. But,
Earth will get attracted more than the water on the other side. This is
what gives the midnight tide.
Jasjeet S Bagla
There is an excellent explanation (with diagrams!) in Paul Hewitt's Concep-
tual Physics text.
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Update: June 2012