People born between the 19th and 23rd of any month, on the “cusp” during the time the Sun transitions from one zodiac sign to the next, often feel left out of Sun Sign astrology. They’ve heard they “have the traits of both signs,” although nobody tells them which traits. Cusp people are left to figure that out themselves. From Sun Sign books (they have to buy two, one for each sign) or daily horoscopes (they have to read two) they string together character traits they think they might have, or try to blend two daily-horoscope forecasts to get one that seems to apply to them. It’s like do-it-yourself astrology. It never feels right. That’s because it isn’t right.
Everyone has a genuine Sun sign. Cusps defined as “two or three days before and after the Sun changes signs” accommodate the fact that Sun Sign astrology—invented in the 1930s—doesn’t require a birth chart or even a birth year: only a birthday. Sun Sign personality assessments and forecasts are general because the reading considers only a person’s Sun position. Everyone has eight more planets, and 12 houses, and much more in their charts that Sun-Sign astrology ignores. That leads to Sun Sign stereotyping.
Kim Kardashian, for example, was born on October 21, and those too lazy to Google her birth year, 1980, and computer-calculate that day’s chart might call her a Libra-Scorpio cusp and leave it at that. But that’s very sloppy thinking, not astrology. The Sun on any day is either in one sign or the next. In the most-used type of astrology there exist borderlines between signs, crystal-clear and permanent, although invisible anywhere but on a sky map or horoscope chart.
We don’t even need Kim’s birth time and place (10:36 a.m., Los Angeles) to determine that on October 21, 1980, the Sun was in Libra. On that day it was one degree away from being in Scorpio. But the Sun was still in Libra. Kim’s a Libra. It’s wrong to characterize her further by borrowing random stereotyped Sun Sign traits from Scorpio. (“Hey, she’s sexy! That’s because she’s part Scorpio!”)
If you were born between the 19th and 23rd of any month, online calculators can tell you your true Sun Sign. The simplest we’ve found, and you don’t have to give your name, is Lunarium’s calculator at http://www.lunarium.co.uk/. Your Sun position can be anywhere from 0 degrees to 29 degrees of a zodiac sign. Please note that Lunarium is a British site and the British sometimes call Sun Signs “star signs.” That’s not wrong, it’s just how they say it.
If your natal Sun comes out at 0 degrees or 29 degrees of a sign, then you might be the rare exception: a person truly “born on the cusp,” which professional astrologers define extremely precisely, not “a few days before and a few days after.” In fact the window for a genuine cusp is one hour. As seen from Earth, the Sun’s disk measures one degree in diameter. For a brief moment in the sky the Sun’s center is exactly on that invisible line between signs. That’s the cusp. This cusp lasts one hour, or 30 minutes on each side. Only those born within that hour were truly born on a cusp. Prince George of Cambridge (July 22, 2013, 4:24 p.m.) was born just seconds, a mere breath, before the Sun moved from Cancer into Leo. His Sun is technically in Cancer, but he’s a genuine Cancer-Leo cusp.
Of course calculating this requires an exact birth time, and birth times are notorious for being inaccurate—most witnesses being too busy to watch the clock. And then there’s the question of whether the clock is accurate. But you needn’t bother because there’s no benefit to having been born on a genuine astrological cusp. You get no special gifts or traits from the Sun or stars. It’s back to “half of one sign and half of the other.”
Everyone else born between the 19th and 23rd of any month can calculate and enjoy their new status as a real 100 percent undivided Sun Sign.