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About how much time passes between one high tide and the next high tide? From one low tide to the next low tide?
It's (very roughly) 12 hours from one high tide to the next, and of
course the same for low tides. That's because the tides produced when
the Moon is directly overhead or in the opposite dirction are the same.
The Moon passes directly overhead about once per day, due to the
To be more precise, it's about 12 hours and 25 minutes between
high tides, when you take into account the Moon's orbit around the
Earth. Since there are weaker tides from the Sun, those can change the
periods on particular days, dependeing on whether they are in-phase or
out-of-phase with the Sun tides.
(republished on 07/12/06)
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