Welcome to SkyTours with Derrick! If you've ever found yourself under the night sky wondering what that thing is, well, you've come to the right place to find out. I'll provide regular postings of just what's available for you to see at this time of this year, including planets, stars, constellations and my favorite - satellites! I'll also welcome your suggestions for what to add to the blog for your information and answer your questions.

Tuesday, May 1, 2012

SuperMoon 2012

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!