The first in a series of three full supermoons will appear in the night sky Aug. 29.
The term, coined by astrologer Richard Nolle more than 30 years ago, is used to describe a new or full moon that coincides with the moon reaching its closest point to Earth on its orbit.
According to astronomers at EarthSky, a new or full moon has to come within 224,834 miles of the Earth to be considered a supermoon.
There were three new supermoons to start 2015, occurring in January, February and March.
With the Aug. 29 moon — which will rise at 7:52 p.m. — at its closest approach to the Earth, it might look slightly larger and brighter than usual. The moon will be 223,639 miles from Earth that night.
The full moon will impact the tides that day. At the Tacoma Narrows Bridge, the low tide of minus 1.2 feet will occur at 11:28 a.m. The high tide will reach 13.0 feet at 6:15 p.m., a swing of more than 14 feet.
In Olympia, the low tide in Budd Inlet will be minus 1.3 feet at 12:02 p.m., with the high tide of 15.1 feet at 6:32 p.m.
Aug. 29’s celestial events kick off three consecutive months of full supermoons. The others will occur Sept. 27 and Oct. 27.
The September supermoon will coincide with a total lunar eclipse. While it will be visible in the Northwest, the timing is such that residents of the region will miss the start of the eclipse. That’s because the eclipse will begin before the moon rises. The eclipse will begin at 5:11 p.m., with the total eclipse beginning at 7:11 p.m. The total eclipse will end at 8:23 p.m. and the eclipse will end at 10:22 p.m.
The moon will not rise that day until 6:55 p.m.
The full moon on Sept. 27 will be the closest supermoon of the year at 221,754 miles from Earth. It marks the end of a series of blood moon eclipses that started with the total lunar eclipse on April 15, 2014.