Constellation of date and the actual constellation that follows the sun

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Discussion Overview

The discussion revolves around the relationship between zodiac constellations and their positions relative to the sun, specifically addressing the angle difference between the actual constellation and the zodiac sign associated with a given date. It explores the concepts of the Tropical and Sidereal zodiacs and their implications on the perceived movement of constellations.

Discussion Character

  • Conceptual clarification
  • Debate/contested
  • Technical explanation

Main Points Raised

  • One participant notes that each month a different zodiac constellation follows the sun, suggesting a distinction between the "constellation of date" and the actual constellation that follows the sun.
  • Another participant introduces the Tropical and Sidereal zodiac systems, explaining that the Sidereal zodiac is based on the Earth's position within the galaxy, while the Tropical zodiac is based on the seasons marked by the vernal equinox.
  • It is mentioned that the two zodiac systems are drifting apart over time at a rate of 1.4 degrees per century, indicating a potential source of confusion regarding zodiac signs and their corresponding constellations.
  • A later reply suggests that the regression of any Right Ascension (RA) and Declination (DEC) can be calculated based on this 1.4 degrees per century drift, implying a method to determine historical positions of constellations.

Areas of Agreement / Disagreement

Participants present differing views on the significance of the Tropical versus Sidereal zodiac systems and their implications for understanding the constellations' movements. The discussion remains unresolved regarding the specific angle difference between the actual constellation and the zodiac sign for a given date.

Contextual Notes

The discussion highlights the complexities of zodiac definitions and their astronomical implications, including the dependence on Earth's position and the definitions of the Tropical and Sidereal systems. There are unresolved assumptions regarding the calculations and the historical context of the constellations.

Philosophaie
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Each month a different zodiac constellation follows around the sun day and night.

The constellation is in the house of the zodiac sign but the actual constellation is the zodiac before.

Example: the constellation of date is Libra but the constellation that follows the sun around is Virgo.

My question is what is the angle difference between the actual and when original constellation of date went around the sun.
 
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There are two major forms of signs. The Tropical zodiac and Sidereal zodiac

The Sidereal signs set their dates relative to the Earth's position within the Galaxy.

The Tropical signs are dependent upon the vernal equinox (seasons) to set dates.

The different stabilities of these two sources for the signs are causing them to drift apart over time.

Also, the Constellations do not travel around the sun. They appear to move because of the Earth's relative position which changes the backdrop behind the Sun.
 
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Oh and after checking wiki (I know, an excellent source), the two signs drift apart at 1.4 degrees per century.
 
So you plug in any RA and DEC the regression will be 1.4 degrees per century. That will be its position however many centuries ago.
 
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