Thursday, December 11, 2008

Sometimes it's not all dark alerts us to the Biggest Full Moon of the Year:
It's no illusion. Some full Moons are genuinely larger than others and this Friday's is a whopper. Why? The Moon's orbit is an ellipse with one side 50,000 km closer to Earth than the other: see diagram. In the language of astronomy, the two extremes are called "apogee" (far away) and "perigee" (nearby). On Dec. 12th, the Moon becomes full a scant 4 hours after reaching perigee, making it 14% bigger and 30% brighter than lesser full Moons we've seen earlier in 2008.
I was treated to quite a fantastic view of the almost-full moon this morning as I was driving to work.  I leave home at 5:30 in the morning.  I did notice it was very large and impressive, and turned an eerie dusky orangish-yellow just before it set.

1 comment:

  1. It's a good thing the sun stays constant in relation to the earth, otherwise people might not believe AlGores' *effect causes the cause* of greenhouse gasses and man made global wrming.