Judy Isacoff: Perigee moon brings super moon, super tides
Will Sunday's full moon be the greatest of the year?
It coincides with perigee, when moon and Earth are closer to each other than at any other time in 2014. The orbit of our natural satellite around our planet is an ellipse, not a circle. Each month there's a perigee and an apogee position of the moon: At perigee it is nearest Earth for the month and at apogee it is furthest from Earth. Be there when the Full Grain Moon rises in the east at 7:45 Sunday-- it will be closer than during any other month.
The average distance between Earth and moon is 239,000 miles. Sunday, at 221,765 miles distant, our natural satellite is measurably larger than other full moons. It might not be perceptibly larger because we are wowed by most full moons rising and setting. The name "super moon" was coined by Richard Nolle, an astrologer, in 1979. Perhaps all full moons are super moons. See the perigee super moon set in the west at 7:01 tomorrow morning. Tides are greatest when the sun, moon and Earth are aligned at new and full moon every month. Tides are greater still in response to the enhanced gravitational force exerted when the moon and sun are closest to our planet.
On the occasion of New Year's 2014 there was a coinciding new moon, perigee and perihelion (Earth closest to the sun). At that time, astronomer Bob Berman said, "I expect proxigean tides super tides. Usually they occur one day after the new or full moon, not on the day itself. The watery bulge needs a bit of time to catch up to what's happening in space. Aug. 10 the moon is about 17 miles closer though ..."
For those not near the sea, proxigean tides might be evident on the nearest tidal river, which, for us, is the mighty Hudson.
To contact Judy Isacoff go to: www.naturesturn.org
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