Sciency Words: Supermoon

Hello, friends!  Welcome to Sciency Words, a special series here on Planet Pailly where we talk about the definitions and etymologies of science or science-related terms.  Today’s Sciency Word is:

SUPERMOON

I was recently part of a comment thread over on Scott’s Sky Watch.  We were talking about the term supermoon, along with other weird moon names like wolf moon, blood moon, harvest moon, corndog moon, flower power moon, gingivitis moon… you get the idea.  After that, I thought a Sciency Words post on “supermoon” was in order.

The term supermoon was coined by American astrologer (repeat: astrologer, not astronomer) Richard Nolle.  The term first appeared in an article Nolle wrote in 1979 for Horoscope magazine.  To quote Nolle himself from this 2011 webpage article, the term supermoon describes:

[…] a new or full moon which occurs with the Moon at or near (within 90% of) its closest approach to Earth in a given orbit.  In short, Earth, Moon and Sun are in a line, with Moon in its nearest approach to Earth.

This particular alignment of the Sun, Moon, and Earth is also known as a syzygy-perigee.  Perigee means the point when as object orbiting Earth comes closest to Earth, and syzygy refers to the straight line alignment of three celestial objects.

A syzygy-perigee has a marginal effect on Earth’s tides, and if the Sun and Moon are on opposite sides of the Earth (as depicted in the highly technical diagram below), then the Moon will appear to be slightly larger and slightly brighter than normal in our night sky.  Astrologers would have more to say about supermoons, but from an astronomy perspective we’re pretty much done here.

Personally, I don’t really have a problem with the term supermoon.  When the full moon or new moon happens to be 90% closer to Earth than usual, that’s kind of neat.  Sure, the term started as an astrology thing, but there’s a long history of astrology concepts and terminology being borrowed by astronomers.  Supermoon is no different.

And supermoons do tend to get a lot of attention in the popular press.  I’ve had a lot of awesome conversations with people about the Moon and space and science in general that started because of a news report about the latest supermoon.  I think that’s great.  Anything that gets people to take an interest in science is a positive thing in my book.

On the other hand, a few of those conversations have ended with people asking me about their horoscopes, which is a bit disappointing.

Next time on Planet Pailly, please don’t hate anybody, not even the people who deserve it.

Sciency Words: Syzygy

Sciency Words Logo

Science fiction uses scientific language as a form of artistic expression.  With that in mind, today’s post is part of a series here on Planet Pailly called Sciency Words.  Every Friday, I’ll bring you a new and interesting scientific word to help us all expand our scientific vocabulary.  Today’s word is:

SYZYGY

Syzygy: (noun) The word that proves that yes, “y” really is a sometimes vowel.  Whenever three celestial bodies, like the Sun, the Moon, and the Earth, form a straight line, they are in a state of syzygy.  This occurs whenever we have a solar or lunar eclipse, but it can happen in other circumstances as well.  For example, if Venus, Mars, and Jupiter lined up perfectly, that would also be considered syzygy.

The word syzygy has a nice, exotic sound to it, which is appropriate for such a rare astronomical event.  It’s unfortunate you don’t hear the word used more often whenever it actually occurs.  In fact, the word is so obscure that I have never found a way to use it effectively.  It’s almost impossible to make its meaning clear without explicitly giving the definition, which usually means it’s easier to just not use the word at all.

So I challenge you to find a way to fit this word into a story or a casual conversation.  Bonus points to anyone who does it without having to explain what it means.

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Did you already know this word?  If so, please share another sciency word in the comments below.  That way, we can all keep expanding our sciency vocabularies together!