This year, the nearest (and, thus biggest and brighest) supermoon of the year rises on April 7–8. This is 2020 supermoon season with three in a row, in March, April, and May. How big or bright will the Moon appear? What is a supermoon? And why don’t we use this term in The Old Farmer’s Almanac? Here are more helpful facts from Bob Berman.
Super Pink Moon of April
On Tuesday, April 7, at 10:35 EDT, we mark the full Moon of April. It’s the nearest (and, thus, biggest and brightest) supermoon of the year!
Based on a longtime Almanac tradition, we give each lunar month a nickname and April’s Moon is called the “Pink Moon.” No, it’s not because it will turn pink (though a Moon low in the sky will look pinkish). The name speaks to wildflowers called creeping phlox, ground phlox, or moss pink, one of the early spring flowers which blooms at this time.
See all about the Full Pink Moon of April.
What is a “Supermoon”
If you’re a longtime reader of The Old Farmer’s Almanac, you may notice that the pages of the Almanac make no mention of the term, “supermoon.” Nor do any of the world’s astronomical publications. What gives?
The story is simple.
When the Moon is at its closest distance to Earth, astronomers call it perigee. This is because the Moon’s orbit isn’t a perfect circle but elliptical. It’s been called perigee for centuries. Conversely, apogee is the Moon’s furthest point from Earth in its orbit. Learn more about perigee and apogee.
Astronomy publications offered monthly tables showing when the Moon would be closest (called “perigee”) or farthest (“apogee”) were generally ignored except by fishermen and others who cared about the tides.
Now, when a Full Moon or New Moon happens on the same night the moon reaches perigee (the closest distance to Earth), the term is “perigee-syzygy.”
In 1979, an astrologer (not astronomer) Richard Noelle created the term “supermoon” as a sort of synonym for perigee-syzygy. The catchy term sufficiently caught on to make some media outlets say things like, “Go out Saturday night and see the super moon!”
The full Moon. Credit: NASA.
Can You Tell the Difference?
There really isn’t something different to see.
Technically, supermoons are seven percent bigger and 15% brighter. Without reference though, it’s not enough of a variation to be noticeable.
This difference happens because the Moon’s elliptical orbit makes it continually alter its distance from us. Since its out-of-round orbit changes shape depending on whether its long axis is aimed toward the Sun on any particular day, the Moon’s nearpoint itself varies.
Even professional astronomers cannot look at the Moon and tell whether it’s closer or farther from us than average. So a lunar “close approach” is visually a non-event.
How Many “Super” Moons in 2020?
Let’s look more closely. In order of nearness, there are three Super Full Moons and three Super New Moons (the latter aren’t visible) in April (full Moon), October (new), March (full), November (new), September (new), and May (full).
* February is debatable. Credit: NASA.
April 2020 is indeed the year’s closest perigee full Moon, three miles closer than the one involving the new Moon in October.
But wait … The Full Moon of May, distance-wise, earns sixth place out of the year’s 13 Full Moons. It’s right in the middle. So why would anyone call that a “Supermoon?” Yet there it is, the third full Moon member in this supposed Super Moon “series” of six.
You can see why the world’s astrophysicists – and the pages of the Almanac – mainly ignore this whole business.
Does the Supermoon refer to something extraordinary, either in appearance or in rarity? What do you think? If not, then it’s also hype by definition, having the potential to disappoint those who look up and then see nothing out of the ordinary.
And now that we’ve explained it, you’ll know why it’s not in the astronomical tables of The Old Farmer’s Almanac itself. It has nothing to do with our intrinsic joy of gazing at the night sky!
We live in a time when there are truly extraordinary objects and visual events to enlighten the public about. A total solar eclipse. A good auroral display. A rare planet conjunction like the one this coming December 21. Even the half Moon through any cheap telescope. Those are visual examples of things that truly appear “super.”
So, why are Supermoons interesting to us?
The full Moon is always a wonder to see! (A quarter Moon is even more interesting!) Our only satellite and companion is a daily part of our lives. It’s a common point of connection across our planet—and that sense of a global community may be as relevant to us now as ever.
Tell me: What do you think, readers?