Many of you are likely contemplating weekend plans since Saturday is Cinco de Mayo, but there may be another event to pencil into your calendar: viewing the "super moon." At 11:35 p.m. ET Saturday, the official full moon will occur at the same time its orbit brings the familiar white globe closest to Earth.
The moon will appear very large and bright in the sky, about 16% brighter than usual. The best location to view the moon at its largest is when it is along the horizon after rising and just before setting. Viewing the moon behind buildings and trees creates an optical illusion so it appears even larger, making it a perfect time to try and grab some beautiful pictures.
So why is this full moon "super"? As the moon orbits the Earth, there are specific times when it is closest to and farthest away from our planet. Apogee occurs when the moon is farthest away from Earth, and perigee occurs when it is closest. On Saturday, the moon will be at its perigee and thus very close to Earth – about 221,000 miles away.
The perigee on Saturday night will also be the closest one to Earth all year, about 3% closer than any other approach in 2012. This is due to the fact that the orbits in our solar system are elliptical instead of circular. There is a bit of wobble in these orbits as well, explaining why we see some perigees closer and some apogees farther away than others.
Those along the coasts wondering, “Do I need to worry about huge high tides?” will notice more exaggerated high and low tides but nothing extreme. In most places, the perigean tides raise tidal levels about an inch. In some locations, the tide could rise possibly up to 6 inches, depending on local geography.
This full moon will be big, bright, beautiful and certainly worth a look. The timing to see it will be perfect when many people already are out and about on Saturday night.