Supermoon!June 20th, 2013 at 10:55 pm by Bill Steffen under Bill's Blog, Weather
This pic. from Wikipedia shows the difference between an average full moon and a “supermoon”. This weekend we have what’s called a supermoon. That term came from an astrologist in 1979. Astronomers call this a perigee moon. This full moon will be (by a small percentage) the closest and brightest full moon of the year. The term “supermoon” was coined in 1979 and refers to a full moon that occurs when the moon is closest to the Earth in its elliptical orbit. The point when the moon is closest to the Earth is called perigee. When the moon is farthest from the Earth, that’s apogee. The full moon occurs at 7:32 AM EDT on June 23rd (Sunday). That’s only 22 minutes from perigee. A supermoon like this occurs every 14 lunar months (a lunar month is roughly 29 1/2 days). At the time of this full moon, the distance from the Earth to the moon will be 221,824 miles. Two weeks later, the moon will be at apogee and the distance from the Earth to the moon will be 252,581 miles. The next time we have a supermoon like this will be August 8, 2014. The full moon of Nov. 14, 2016 will be slightly closer at 221,524 miles (the closest moon until 11/25/2034). Closer full moons occur on 12/6/2052 (221,472 miles) and if you really want to see the closest, biggest and brightest full moon, that’s on Jan. 1, 2257 at 221,439 miles (I’ll hobble out with my cane to see it!). Here’s this week’s Sky at a Glance, a summary of this week’s planets, stars, moon and other astronomical highlights. Here’s when you can see the International Space Station flyover (as well as flyovers of ATV4 and Progress51P). Here’s a list of open house nights at the Veen Observatory, the Muskegon Astronomical Society, the Abrams Planetarium at Michigan State and the latest from the Kalamazoo Astronomical Society.