Managing Multiple Moons

(Based on a piece written for the Eight-of-Dreams Holt Handbook in 1993, substantially revised for Sendings in 1998.)

Impossible Crescents, from old WD

There is a very subtle astronomical principal which is adhered to in the Pinis' work, because Richard is an astronomer and knows this stuff cold. However, the other Elfquest writers/artists have been known to slip up (see old WaveDancers #3, ninth page, first panel, for an example of something that can't happen: the panel shows two crescent moons, right next to each other, whose horns point in opposite directions). The fact is, the phase of the moon depends on its position in the sky and the time of night. This fact deserves a bit more explanation.

You probably conducted an experiment in a darkened room in school when you were about twelve years old, using a light bulb, a beachball and a baseball. Your teacher showed you how, to a viewer on the surface of the beachball, the baseball's lit surface looks like a crescent, a half-moon shape, and so on, changing as it circles around the beachball. If you recall that experiment, or recreate it in your home today, you'll understand why it is that: if it's sunset and the moon is rising, it must be a full moon; if it's sunset and the moon it at its zenith (highest point in the sky) it must be a half-moon, and so on. On the ~~Beachball of Two Baseballs~~ World of Two Moons, this same astronomical principal holds. It follows that:

if the two moons are in the same phase, they are in the same part of the sky, and vice versa.
if the two moons are in different phases, they are in different parts of the sky, and vice versa.

Illustrations showing examples of both positions of the moons in their orbits and how the scene would look to a certain stargazing elf on the planet's surface may help you to visualize this. (Drawings are not to scale!)

In Figure A, the greater moon is opposite the Daystar and the lesser moon is about forty-five degrees away. The position of an observer is marked by a sending-star on the night side of the planet, where it is midnight. The observer sees the greater moon as full and the lesser moon, half-way up the sky, as three-quarters full.

In Figure B, the moons are on opposite sides of the planet, perpendicular to the direction of the Daystar. The observer sees two half-moons on opposite horizons, one rising and one setting.

In Figure C, both moons are to one side of the planet, nearly in the direction of the Daystar. The observer sees two crescents, with their horns pointing away from the horizon where the sun has recently set.

Finally, Figure D shows a configuration in which the horns of two crescent moons would point in opposite directions - however, an observer will not be able to see both moons at once. The Daystar is between the two moons, as seen from the planet's surface. Before the sun rises, or after it sets, only one moon can be above the horizon. While the Daystar is in the sky, the crescents are washed out to invisibility by its glare.

Now you know how to keep your stories and artwork "astronomically correct." You wouldn't want Skywise to snicker when he looks over your shoulder!

A Postscript!!

There is another scene with the two moons next to each other, in seemingly different phases, that I ran across the other day. Initially I thought "Hey! That's not possible!" This is from the Jink story (at the end of "Mindcoil Part 1 - Blue Mountain, Black Snake" in the Reader's Collection Book 14a: Mindcoil, or Elfquest: Jink! #7), the scene where Jink breaks in to Kullyn's apartment for a good romp. It looks like the greater moon is full and the lesser moon is new - but, they're right next to each other in the sky. (The effect is more pronounced in the black-and-white Reader's Collection version.) By the reasoning given in the article above, a new moon and a full moon can't both be in the sky at the same time. A new moon would be setting just as a full one was rising at the opposite edge of the sky (or vice versa).

After I slept on it, though, I realized how the scene could happen. Suppose both moons are full. Now, suppose that the smaller moon is undergoing a lunar eclipse. When the eclipse is total, the moon looks like a new moon, dim in comparison to its uneclipsed companion. Problem solved, and no need to doubt the astronomical acuity of Jon Ostrander, Wendy Pini, Dennis Fujitake, Paul Abrams, or their Persnikety Editor.

Now you are asking, "Linda, what about the WaveDancers scene? Couldn't that be due to an eclipse situation also?" Well, I admit that if you squint your eyes (and cross'em a little), the darkened parts of the two moons in the WaveDancers panel mentioned above could kinda look like a single dark circular shadow. So maybe those crescents are really two full moons, each partially eclipsed. I don't buy it, though. First off, the terminator (the transition from light to dark) during an eclipse is fuzzy. That's because of the light being scattered by the atmosphere of the planet (in this case, Abode). The terminators in the WaveDancers picture are sharp. Second, the shadow of the planet is large and round, so it shouldn't throw such a sharp curve on the smaller moon. And third, I get the impression that the WaveDancers writers/artists had less rapport with Richard than any of the other Elfquest writers and artists - so if there are to be any astronomical errors in Elfquest, WaveDancers is where I would expect to find them.

Oh, before I forget - Elfquest art copyright 1999 Warp Graphics, Inc. Elfquest, its logos, characters, situations, all related indicia, and their distinctive likenesses are trademarks of Warp Graphics, Inc. All rights reserved.

Last updated on April 22, 2001.

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