Monday, January 5, 2009

9.13 Five-, 6-, 7-, 8-pointed stars

How many points does a star emanate?

It depends on where you are from.

In the US, five (5). You see 5-pointed stars on a certain sidewalk in Hollywood (e.g., left). Even the Texaco logo has such a star. It is also the basic standard emblem of the US Military. The American flag has 50 such stars. And the national flags of Singapore, New Zealand, Pakistan, Turkey, China, Somalia, and many others all have the 5-pointed star(s) as part of the design.

There are of course the 6-pointed stars, e.g., the Marian star and the star of David.

The municipal flag of Chicago has four 6-pointed stars (right), each commemorating a specific event and each of the 6 points, a special meaning. A fifth star has been proposed on more than one occasion, but none has been realized thus far. Further, the white stripes = north, west and south sides of Chicago, and the two blue stripes = Lake Michigan and Chicago River, respectively.

Interestingly, the 6-pointed star is also a sacred Mongol symbol, seen, e.g., on the entry to Humayun's tomb in New Delhi (below):

Seven-pointed stars? Of course, the Australian flag has 5 of them:

It often puzzles the tourists: 6 states + 2 territories = 7, not 8 points? (Dared to be different, these Aussies?)

Actually, it is a bit more complicated than the simple math. The winner of the original flag design (contest conducted in 1901) had 5, 6, 7 and 8 points (below, left).

King Edward VII approved the current 5- and 7-pointed star version.

There have been many iterations on the significance of these designs which we'll leave to the real historians to contemplate.

The only national flag that has an 8-pointed star seems to be that of Azerbaijan (below). This star is supposed to be the symbol of Rub El Hizb (Arabic: رب الحزب‎). And the design here was modified in 1991:
Seriously, how many points of a real heavenly star are we supposed to see? Let's see:

In the human eye, the crystalline lens is composed of a single-cell-layer epithelium in the front and a cortex that envelopes the nucleus. The epithelial cells elongate into cortical fiber cells and the ends are jointed at the front and the back, known as the sutures. The front suture is shaped as an upright Y and the posterior, an inverted Y. Superimposing the two Ys, what do you get? Yes, 6-points. This is the basic pattern. Often there are branches off the basic Ys. In other words, stars (in effect, point sources of light) should appear 6-pointed (with/without branches) to most of us. If you see 5 or 7 points, have your eyes examined.

Occasionally, something goes wrong with the sutures, then you'd end up with sutural cataracts. A real bad case is shown here:
See the huge Y within the dilated pupil? Most sutural cataracts are, however, less dramatic than the one shown here. Most have no significant impact on vision except the 6-pointed stars look even more prominent.