Extra-supermoon, the largest and brightest full moon of the year, will be rising on the evening of Sunday, August 10.
The lunar show is the second act in a trio of supermoons that are gracing our skies this summer.
The moon will be at its closest approach to Earth for 2014, at 221,765 miles away, while in its full phase this week it will appear 16% larger and 30% brighter than usual.
The astronomical community uses the term “perigee full moon,” and point out that they are not all that rare since the alignment between a full moon phase with perigee occurs every year.
In 2014 there are three supermoon: on July 12, August 10, and September 9, when the moon becomes full on the same day as perigee.
The monthly full moon always looks like a big disk, but because its orbit is egg-shaped around the Earth, there are times when the moon is at what astronomers call perigee – its shortest distance from Earth in the roughly month-long lunar cycle – or it can be at apogee, its farthest distance from Earth.
Likewise, because the size of the Moon’s orbit varies slightly, each monthly perigee is not always the same distance away from Earth.
This weekend, perigee will occur only 26 minutes before the moon officially reaches its full phase at 18:10 Universal Time (2:10 p.m. EDT) on August 10.
At that specific time, the moon will be straight overhead in the sky above the Indian Ocean.
Such tight timing won’t occur again until 2034.
For moon-watchers and photo hounds, the best time to catch all the action is just after your local sunset on Sunday, just as the full moon begins to rise.
An optical illusion known as “the Moon Illusion” makes the moon appear larger near the horizon. Because of the Ponzo effect, our brain is tricked into thinking the lunar disk is larger than it is.
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