Look! Up in the
air! It’s a bird! It’s a plane! No, it’s
SUPER-MOON!
This month’s full moon occurs this Saturday, May 5th at
11:35 p.m. It coincides with a minimum
perigee just one hour earlier, bringing the moon 3 percent closer to Earth than
average perigees. The result? The moon will appear 14% larger and 30 percent
brighter than other full moons this year – a super moon.
The elliptical shape of the moon’s orbit allows for both a
minimum distance and a maximum distance from Earth. The minimum is called
‘perigee’ (‘peri’ - Latin for close to, ‘gee’ - Earth), the maximum is ‘apogee’
(‘apo’ Latin –‘far from’). The moon’s
orbit also slowly rotates around Earth. This means the dates for perigee and
apogee gradually slide along the calendar from month to month.
Although an optical illusion already causes the moon to
appear unusually large at moonrise, with a minimum perigee 3% closer than
average, the full moon will appear even larger when it rises Saturday at 7:49
p.m EDT.
Is it really ‘super’? Only as far as ocean tides are
concerned. With this ‘close’ close approach, the moon will exert 42 times more
force on tides than it would at the next apogee two weeks later.
Will the close approach cause any disasterous effects? Nope.
No earthquakes, tidal waves, crime sprees, heart attacks, or volcanic
eruptions. ‘Supermoon’ actually happens once a year, quite frequently when
measured in geologic or even astronomical time. And it seems the earth has
managed to survive each time.
Then why do we call it ‘super’? As Madison Avenue has
directed us, everything should sound more attractive or interesting when
supersized! Well, almost everything….
Great time to get a ‘moon-tan’ or blame your drunken walk home Saturday
night on the extra gravitational pull of the moon. Enjoy!
