A closeup view of a "supermoon." (NASA photo)
Skies in the Pacific Northwest have finally started to clear, which should bode well for stargazers hoping to catch the supermoons coming this season.
There will be several big moons in 2021, according to astronomers, most notably the full moons on April 26 and May 26, the latter of which will take place during a total lunar eclipse.
The term “supermoon” is unofficial, though it is generally thought of as a full moon that is a little larger and brighter than normal as it reaches its closest point to Earth. Because the moon follows an elliptical path around the Earth, its distance from our planet (known as the perigee) varies throughout the year.
Scientists refer to the phenomenon as “perigee syzygy,” meaning the alignment of the Earth, moon and sun at the moon’s closest point in its orbit. It could occur during either a full moon or a new moon, though full moons naturally receive all the attention.
The term “supermoon” was coined not by an astronomer but by astrologer Richard Nolle, who in a 1979 magazine article said he considered the moon to be “super” when it is within 90% of its closest approach to Earth in a given orbit. In 2000, Nolle published a chart listing every supermoon for the next 100 years, according to his calculations, posted online at astropro.com.
Over the years, different organizations have used different calculations to determine what, exactly, counts as a supermoon, with most landing on a perigee of 223,000 to 225,000 miles. That difference occasionally invites disagreement about how many supermoons there are in a given year.
Two of this year’s full moons are inarguably super. The April 26 full moon will come within 222,064 miles of Earth, and the May 26 full moon will be the closest of the year at 222,023 miles, according to timeanddate.com.
The April full moon is often called a “pink” moon, not because it will be pink, but because it corresponds with certain early-blooming flowers in spring, according to the Old Farmer’s Almanac. The full moon will rise at 7:57 p.m. on April 26 in Portland, and those hoping to get a good photo will want to catch it as it just begins to rise over the southeast horizon, when it will appear even larger due to the “moon illusion” effect.
The May full moon, which is sometimes called a “flower” moon due to the abundance of spring flowers, will also take place during a total lunar eclipse, according to NASA, in what is perhaps the most anticipated astronomical event of the year. Those awake in the wee hours of the morning of May 26 will be able to see the eclipse begin at 1:47 a.m. in Portland, reaching totality around 4:11 a.m.
Some may consider the March 29 and June 24 full moons to be supermoons, since both come within 224,000 miles of Earth, but Nolle’s charts don’t include them. His charts do, however, include the Nov. 4 and Dec. 4 new moons, which occur during the moon’s closest perigee all year, though, again, the new moon is practically impossible to see at night.
Regardless of how you define a supermoon, the full moons this spring truly will be a sight to behold, shining just brighter in the night. And while the increased size is small enough to be imperceptible to many, a supermoon is always a good excuse to go outside and appreciate the beauty of the night sky.
This story published with permission as part of the AP Storyshare system. Malheur Enterprise is a contributor to this network of Oregon news outlets.