(Here is a repeat from 2014 from long-time editor Mike Brown about Supermoons.)
EDITOR’S CORNER
MIKE BROWN
Warning, old guy about to go off on a rant that won’t make any difference.
I feel sad, and just a little angry, every time I see a news story about a “supermoon,” you know, the ones that say it’ll be 10, 50, 100 times bigger or brighter than usual, whatever “usual” means for something that’s always changing.
Let’s get this straight right away.
There is no such thing as a supermoon. Period.
The moon’s orbit is not a circle. It’s an ellipse. (Not “eclipse,” Facebookers, that’s different.)
Because it’s an ellipse the moon gets closer and farther away in its monthly orbit. Farthest away is called an “apogee,” closest approach is a “perigee.”
Occasionally a full moon will occur near a perigee. Is it so rare “no one alive will ever see this again” as some Interweb posts proclaim (at different times)?
It’s happening three times this year. In fact it happens most years.
Yes, the full moon’s apparent diameter and brightness can vary. But the question is, can you tell the difference just by looking up, pointing with your Bud Lite can and going “Dang, Bubba, bring me the mosquito spray.”
The moon is very bright. It’s also very small. It’s onehalf degree wide.
You know those 7-by-35 binoculars that don’t magnify very much even when you look through the correct end? You could line up 14 moons in them.
If you hold up an index card, or ruled sheet of paper by side of the full moon in the sky, you can see it looks about as big as the spaces between the lines. All the time.
Why would astronomers call an event a “supermoon” then?
Answer is, they don’t. The term was coined in 1979 by an astrologer, Richard Nolle.
(An astrologer is someone who makes stunning life suggestions for you, like: “Tuesday will be a good day for you to breathe both in and out!)
Nolle coined the term to promote his crackpot theory that supermoons cause disasters like earthquakes, volcanoes, tsunamis or the 2012 National League playoffs.
The term languished in obscurity until 2011 when, two weeks after a perigee full moon—when the moon had moved thousands of miles farther away than its closest approach that month—a tsunami and earthquake triggered a nuclear disaster in Japan.
That’s when our social media and science-challenged news media picked up the “Supermoon” term.
Well, what about those pictures we see all the time of giant moons? Many are long-focus telephoto shots of the moon rising or setting against objects. Any moon looks huge.
Some are outright fakes. I’ve seen some of the “supermoons” rising over Yosemite or Rio de Janerio which make the moon look like the spaceship in “Independence Day.” And many, taken by well-meaning folks who have been told “it’s a Supermoon, dude!,” just look like, well, full moons.
Some in the science community (NASA, for instance) have just thrown in the towel and are using “supermoon” in an attempt to get people to look up.
Except, a full moon is the absolute worst time to look at the night sky.
Also, at full, the moon has no “terminator,” the line between light and dark where most of the neat detail is.
And, at full, it’s so bright most of the detail is washed out.
So, a supermoon, or any full moon, is also the worst time to look at the face of the moon.
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