Sextile and Orb

How to spot a sextile: count two signs forward or back from the sign a planet is in, and that is where a sextile points. Two signs forward from Aries is Gemini, two back is Aquarius; 10 degrees Aries and 10 degrees Gemini are exactly 60 degrees apart.

A sextile is often read as “an opening, but you have to act”: lighter than a trine, and it does not happen by itself. What the two planets stand for can help each other, but the ease shows up once you speak first or make the first move.

When you find a sextile in your own chart, ask yourself: do the things these two planets stand for go especially smoothly when I take the first step? If you always wait for it to happen, you may never have noticed it.

In this app's aspect list the sextile has the smallest orb (4 degrees in a birth chart), so it is also the one most easily “just off, so it doesn't count.” The next section is about how far off still counts.

What the old texts say: Ptolemy's Tetrabiblos, Book I ch. 13, gives the sextile two-thirds of a right angle, two signs and 60 degrees, and counts it with the trine as harmonious because it joins signs of the same kind.

The orb is the range for how far off still counts. Two planets 63 degrees apart are 3 off a sextile; as long as those 3 degrees are inside the orb, the sextile counts. The less it is off, the “tighter” the aspect; near the limit, it is “looser.”

Books and websites use wider or tighter orbs, so the same chart can list a different number of aspects. When you see someone's list of aspects, you can ask first: what orb was this worked out with?

When you read your own aspect list, look at how far off each one is too: 0 to 1 degree is tight, close to the limit is loose. Start comparing yourself with the tightest few, then move on to the looser ones.

What the old texts say: Tetrabiblos Book I ch. 24 says that when two places are “not far apart,” the one in front is applying and the one behind is separating. So when two places are close, the relation already holds.

Birth chart: 8 degrees for conjunction and opposition, 6 for square and trine, 4 for sextile. Transits are read more tightly: 1 degree in general, 2 for the Sun and Moon, and “exact” means within 0.1 of a degree. These numbers are kept in one table with a version number, and every report records which version it used.

So the same chart may show a few more or fewer aspects somewhere else, and the difference usually comes from how wide the orbs are. Remember which table you are reading and comparisons stay clear.

Try it: pick one aspect in your list, work out how far it is from the exact angle, then compare that with the numbers above to see how far it is from the limit. The further from the limit, the tighter the aspect.