“I am totally stymied by cusps and interceptions,” confided a reader in a recent email. Let’s see if we can sort out this out for you, shall we?

Cusps and Signs

Part of the problem is the term cusp. Specifically, misuse of the term by people who greedily lay claim to two Sun signs.  You may not realize this, but when you talk about “your sign,” you’re actually saying, “The sign of the zodiac through which the Sun appeared to be moving at the time of my birth.” (Didn’t know you were so smart, did you?)

Problem is, because the earth’s annual journey around the Sun doesn’t take precisely one calendar year, the date the Sun moves from one sign to another changes (within one day) from year to year. So if you were born on March 20, then yeah, you might be a Pisces or you might be an Aries.

But let’s be clear: When you were born, the Sun was in one sign, or it was in the next. The only way to know for sure which one is to find out what time you were born and calculate your birth chart. Now yes, if you were born within, say, an hour of the moment when the center of the Sun actually enters a sign, then okay – maybe you could make the case that you are “born on the cusp.” Otherwise, one Sun sign per customer!

And now for something completely different: Cusps and Houses

Since most astrologers wouldn’t be caught dead anywhere near this “born on the cusp” business, when we use the term “cusps” you can be pretty sure that we’re not talking about signs at all. Rather, we’re referring to the lines that separate houses in the horoscope, much as fences separate properties from one another:

And so on, proceeding counter-clockwise, for a total of twelve. When astrologers refer to house systems, we’re talking about different methods of cutting up the sky, and where the cusps should go. And we can get pretty animated on the subject.

Four of the cusps have special names. Sometimes called the angles of the chart, they are:

• First House cusp: Ascendant
• Fourth House cusp: IC or Nadir
• Seventh House cusp: Descendant
• Tenth House cusp: MC or Midheaven

The houses of the horoscope symbolize areas of the sky. For instance, the cusp of the first house represents the eastern horizon, and the cusp of the seventh house represents the western horizon. The cusp of the tenth house represents the highest point in the horizon any planet can reach at a given location, and the cusp of the fourth house represents its opposite point.

So the first, fourth, seventh, and tenth houses actually have a basis in physical reality. As for the rest… look up in the sky, right now; do you see lines there? (I sincerely hope the answer is no.)

It’s true: House cusps are fictional. Convenient, but open to interpretation.

Signs, degrees, and house cusps

Think of the chart wheel as a big ribbon with all 360 degrees of the zodiac lining the inside like dots on wallpaper.  The twelve house cusps are like hands on a clock attached to the middle of the circle, each pointing to a specific dot, or degree, on the wallpaper. If you were born with 15 degrees of Sagittarius rising, that means the first house “hand” was pointing at the middle of Sagittarius. If you were born near the equator, the 2nd house “hand” would be pointing at about the middle of Capricorn, the 3rd house at the middle of Aquarius, and so forth.

The catch: The farther north or south you were born of the equator, and depending on which house system you use, things can get wonky. Some houses can be very large, some very small. Perhaps Sagittarius is on the cusps of both your first and second houses, then Capricorn gets skipped altogether and the third house has Aquarius on the cusp. This is called an interception. Capricorn is still there – it’s just that all 30 degrees of the sign are hidden in the second house, with no clock hand pointing at them. Intercepted signs are like silent partners of the houses that they’re in; the sign on the house cusp does the PR work, while the intercepted sign works behind the scenes.

Next: Can planets be “on the cusp”?

Using house cusps

Some astrologers feel that when a planet falls within a certain number of degrees of a house cusp, it makes its presence felt in both the houses that flank that cusp. How many degrees? Depends on which astrologer you ask – some say as few as three degrees, others as many as ten.

Me, I’m torn about the whole idea. On the one hand, it takes us right back into dreaded “on the cusp” territory, with the same people who are inclined to claim ownership of two signs now claiming that “my Venus is in TWO houses.” Eyeroll.

On the other hand, as mentioned above, houses and their cusps are largely imaginary anyway, and other than the angles, it doesn’t make sense to get too rigid about where one ends and the other begins.

In summary…

• “Cusps” refer to the division between signs of the zodiac or houses in the horoscope.
• Don’t talk about being “born on the cusp.”
• The cusps of the 1st, 4th, 7th, and 10th houses – also called “angles – have special names and a basis in physical reality.
• The rest of the house cusps are a convenient fiction that give astrologers something to fight about over drinks.
• Intercepted signs are those that are fully contained in one house and don’t appear on a house cusp. They express themselves in a more indirect and subtle way, using the sign on the cusp as a PR agent.
• Planets close to a house cusp may be interpreted as being in either or both houses.

Questions about cusps or interceptions? Leave ’em in comments!