Fish Eaters: The Whys and Hows of Traditional Catholicism

"Praise ye Him, O sun and moon: praise Him, all ye stars and light''

Envisioning the Celestial Sphere


Here I want to present a way of modelling the Heavens so you can grasp how the stars move. To understand the motions of the stars, we first have to have a basic understanding of the earth as a sphere, and of the Heavens modelled as a second sphere. For a very simple way of grasping this, imagine the earth as a ball inside another, much larger ball. That larger ball represents the sphere on which the stars seem to be placed. If we imagine that second ball as spinning once a day, from East to West, clockwise when facing North, we can imagine the rotation of the stars.

Now, all of the stars aren't truly placed onto one sphere that is X miles away; some stars are relatively close, and some are far away, but to our eyes, they seem to be on a single sphere, and this gives us a way of modelling the stars' movements: imagine you are a small point on that earth ball, inside the larger, spinning ball on which all the visible stars are painted. Because both the earth and celestial spheres are round, you can only see about half of the star ball at any given location at any given time (neverminding the effect of the Sun's light on the stars' visibility, of course. You won't be seeing them during the daytime unless there's an eclipse.). So, if you were to cut the star ball in half, you'd have a map of the stars you can see at a given latitude (depending on the time of the year, i.e., the position of the Sun).

If you have a half of a ball like that, you can imagine it, if a handle were added, as a very deep, bell-shaped umbrella, and that, to me, is the easiest way to picture all this. Simply imagine an umbrella on which the stars of the Northern half of the celestial sphere have been painted on its underside. Now, hold it out in front of you, its handle parallel to the floor and pointing North, and then tilt it up toward you according to your latitude -- i.e., if you are at 40o latitude North, tilt the umbrella up 40o relative to the floor.

Now take the umbrella and hold it over the edge of a round table, keeping it tilted it toward the North at an angle that matches your latitude. The table represents the ground you are standing on, the edge of the table represents the horizon, and as you spin the umbrella, on its axis, once each day to mimic the spin of the celestial sphere, stars will go in and out of sight as they sink below and rise above the horizon. These stars are always out there, always circling, even during the day time when the Sun's light prevents our seeing them.

Using the Northernmost Stars as an Example of How to Form a Mental Image of the Celestial Sphere

Ursa Minor: At the very tip of the umbrella will be the North Star -- Polaris, a star in a constellation known as Ursa Minor, or "Little Bear." This constellation has a group of stars -- an "asterism," or an easily recognizable pattern of stars that isn't regarded as an official constellation in itself -- that is known as "The Little Dipper," and Polaris is the very tip of the Little Dipper's handle.

If you are standing at the North Pole (at 90o N), Polaris will be directly overhead, so you'd keep the umbrella upright, at a 90o angle from the floor, for your map of the heavens; the stars above your head will appear to move in lovely circles with your position at the center.

If you are around the equator, at 0o latitude, Polaris will seem to be lying directly on the ground in the distance, and the stars that form the cup of the Little Dipper will be quickly going in and out of sight, over and underneath the horizon, circling around it at due North (you'd have your umbrella lying so that its handle is flat against the table).

If you are at around 40o latitude (like Indianapolis and Naples) and tilt the umbrella properly, Polaris will appear to be 40o up over the table-horizon. The measure of the altitude over the horizon of this "Pole Star" will always equal the latitude of the person doing the measuring. It is by knowing this that ancient navigators could always find true North.

Polaris, by the way, is 430 light years away (a "light year" is the distance light travels in one year) -- that is, when we see the star, we are seeing it as it appeared 430 years ago (see this beautiful time lapse photograph that shows the movement of the stars around Polaris, which seems to sit always still over the tip of our globe).
OK, so now that you have a way of envisioning how the stars move, let's begin...

Table of Contents

The Zodiac


A Tour of the Heavens
Envisioning the Celestial Sphere

The Constellations of the Zodiac













Summary and a Few Odds and Ends

The Traditional Catholic View of Astrology

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