06-06-2020, 09:52 PM
JKP, a zodiac sign is one of twelve equal partitions of the ecliptic.
The ecliptic is a circle along the sky, which essentially is the path of the Sun in the course of a year. This means that each sign covers 360 divided by 12 = 30 degrees.
The first sign after the Vernal equinox (21 March) is the sign of Aries. It is called Aries because in classical times it coincided with the constellation of Aries.
The same for the other 11.
The moon and the planets also travel essentially, but not really all that closely, the same path. The moon only needs 2.5 days to pass from one sign to the next (the Sun needs a month). For the planets it's more complicated.
As a result of precession of the Earth's axis of rotation, the correspondence between zodiac signs and constellations was lost many centuries ago.
In modern times, there are actually 13 constellations that include part of the zodiac, and the fraction of the zodiac that is covered by each constellation can be any number, not necessarily 30 degrees.
For ancient and modern astrology, and for ancient astronomy, the only thing that matters is the zodiac sign. Ptolemy used this as one of the two coordinates for every star in his catalogue.
The ecliptic is a circle along the sky, which essentially is the path of the Sun in the course of a year. This means that each sign covers 360 divided by 12 = 30 degrees.
The first sign after the Vernal equinox (21 March) is the sign of Aries. It is called Aries because in classical times it coincided with the constellation of Aries.
The same for the other 11.
The moon and the planets also travel essentially, but not really all that closely, the same path. The moon only needs 2.5 days to pass from one sign to the next (the Sun needs a month). For the planets it's more complicated.
As a result of precession of the Earth's axis of rotation, the correspondence between zodiac signs and constellations was lost many centuries ago.
In modern times, there are actually 13 constellations that include part of the zodiac, and the fraction of the zodiac that is covered by each constellation can be any number, not necessarily 30 degrees.
For ancient and modern astrology, and for ancient astronomy, the only thing that matters is the zodiac sign. Ptolemy used this as one of the two coordinates for every star in his catalogue.