Look, up in the sky. It’s a supermoon.
If one were to travel 30,284 miles, that would be the equivalent to a bit more than six round trips from Tacoma to Tokyo.
In realm of astronomy, however, it is a mere stone’s throw.
But Sunday (Nov. 13) and Monday, that distance will result in what has become the popular lunar phenomena called the supermoon.
The moon’s orbit around the Earth is not a perfect circle. That means at some point during its elliptical trip around the Earth, the moon reaches a minimum distance from the planet (called perigee) and a maximum distance (apogee).
At perigee, the moon will be 221,524 miles from Earth, at apogee, it is 251,808 miles away.
Monday is when the difference — those 30,000-some miles — comes into play.
If the weather cooperates, the moon will seem as much as 14 percent larger and 30 percent brighter as it rises up over the horizon at 4:37 p.m. Sunday and 5:19 p.m. Monday, according to NASA astronomers.
The moon will appear as full Sunday and Monday nights because it actually reaches the crest of its full phase at 5:52 a.m. Monday.
It’s the timing of the full moon coinciding with the moon reaching the perigee on its orbit that will create the largest supermoon since 1948. That’s because, according to NASA, the moon becomes full within about two hours of reaching perigee. It will not happen again until Nov. 25, 2034.
This also is the second in a series of three supermoons this year, with the first in October and the final one occurring in December.
As is always the case when it comes to astronomical events in the fall in the Northwest, the weather will be a big factor. The forecast for Monday evening calls for partly cloudy skies.
The best time to observe the supermoon will be as it rises over the eastern horizon. While just an optical illusion, NASA astronomers said, the moon will appear unnaturally large when viewed through the trees, buildings and other objects in the foreground.
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Meteor shower also on tap
Astronomy fans also will be treated to the Leonids meteor shower this week, but they shouldn’t expect a huge display.
First, this year’s Leonids meteor shower is considered minor, producing up to 15 meteors per hour at its peak. The shower will reach its peak Thursday night and early Friday morning.
Complicating matters, the waning gibbous moon will block the fainter meteors this year. The best viewing will be from a dark location after midnight.
The Leonids is produced by dust grains left behind by comet Tempel-Tuttle, which was discovered in 1865. This shower is unique, according to astronomers, because it has a cyclonic peak about every 33 years where hundreds of meteors per hour can be seen. That last of these occurred in 2001.
This story was originally published November 11, 2016 at 4:43 AM with the headline "Look, up in the sky. It’s a supermoon.."