According to Dr. Marek Kukula, public astronomer at the Royal Observatory, Greenwich, “as a result of this, throughout the last two thousand years the dates at which the Sun seems to move in front of each backdrop constellation of stars has shifted by a few days.”
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Why do dates for various zodiac signs vary?
Aries is the first sign of the zodiac. Every year, the Aries season begins on the first day of Spring; however, this can vary if the year is a leap year.
“When the star signs are determined, we use the first day of Aries on the Spring Equinox, which is March 20 or March 21,” Francesca added.
The date shifts every four years because the equinox happens roughly six hours later to account for leap years.
Do astrological signs alter annually?
What does that meanyour zodiac sign shifts annually? No, it’s closer to every 30 years. (Thank G, you have some time to think about all of this.) The advanced sun only moves by less than a degree per year, therefore there are 30 degrees in each sign, making this transition extremely gradual, according to Montfar.
What influences the zodiac’s dates?
Early astronomers noticed that the Sun passed through each sign of the zodiac once a year, staying there for about a month. They determined that each constellation spans the ecliptic by 30 degrees as a result.
The constellations we see now, however, have changed positions because to a phenomenon known as precession.
The zero point of the Zodiac used to indicate the start of spring in the Northern Hemisphere. The intersection of the celestial equator and ecliptic is where the vernal equinox, as it is known to astronomers, takes place.
The “first point of Aries” was the zero point of Aries around 600 BCE. In (Figure 1) The first 30 degrees of the ecliptic were occupied by the constellation Aries, the next 6060 by Taurus, the next 9090 by Gemini, and so on for all 12 constellations of the zodiac.
The Earth rotates on its axis in a 25,800-year cycle, which the early astrologers were unaware of. The gravitational pull of the Moon on Earth’s equatorial bulge is what causes the wobble known as precession.
The crossing point between the celestial equator and the ecliptic has moved 36 degrees, or about one-tenth of the way around, west along the ecliptic over the past 2,600 years due to this wobble. This indicates that, in relation to the stars beyond, the signs have moved one-tenth or roughly an entire month of the way around the sky to the west.
For instance, people who identify as Aries and were born between March 21 and April 19 do so. Today, the Sun spends most of its time outside the constellation of Aries. The Sun is actually in the constellation of Pisces from March 11 to April 18! In Figure 2 See Figure 3 for an illustration of the equinox precession from 600 BCE to 2600.
The dates that the Sun actually passes through the astronomical constellations of the Zodiac, using current constellation borders and corrected for precession, are listed in the table below (these dates can vary a day from year to year).
You’ll probably discover that your zodiac sign changes when precession is taken into account. And if you were born between November 29 and December 17, you have an astrological sign you’ve never heard of: the Ophiuchus! After Scorpius, the eliptic crosses across the constellation of Ophiuchus.
Visit the Birthday Sky application to see what the sky looked like on your birthday and to view your “true zodiac sign” below.