vernal equinox/Zodiac

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vernal equinox/Zodiac

Postby dehaven » Tue Sep 05, 2017 1:32 am

This is NOT an astrology question. Nor do I believe in astrology.

I am so confused. Any help would be greatly appreciated. I am totally new at this. i am trying to solve a historical question using Sky Safari 5 Pro.

FROM Wikipedia:

Unlike modern astronomers, who place the beginning or the sign of Aries at the place of the Sun at the vernal equinox; Babylonian astronomers fixed the zodiac in relation to stars, placing the beginning of Aquarius at the "Rear Star of the Goat-Fish" (δ Capricorni).

Okay so the vernal equinox has passed or is passing or is about to pass from Pisces to Aquarius. And indeed, in order to move from δ Capricorni to the constellation Aquarius using Sky Safari, I must move BACKWARDS in time.

Why then would Wikipedia state that "Babylonian astronomers [place] the beginning of Aquarius at the "Rear Star of the Goat-Fish" (δ Capricorni)?" Do they simply mean the end of Aquarius?

And why do I have to set the date to December 21, 8000 BC to get the sun between Pisces and Aquarius?
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Re: vernal equinox/Zodiac

Postby Gfamily2 » Tue Sep 05, 2017 12:07 pm

dehaven wrote:This is NOT an astrology question. Nor do I believe in astrology.

I am so confused. Any help would be greatly appreciated. I am totally new at this. i am trying to solve a historical question using Sky Safari 5 Pro.

FROM Wikipedia:

Unlike modern astronomers, who place the beginning or the sign of Aries at the place of the Sun at the vernal equinox; Babylonian astronomers fixed the zodiac in relation to stars, placing the beginning of Aquarius at the "Rear Star of the Goat-Fish" (δ Capricorni).

Okay so the vernal equinox has passed or is passing or is about to pass from Pisces to Aquarius. And indeed, in order to move from δ Capricorni to the constellation Aquarius using Sky Safari, I must move BACKWARDS in time.

Why then would Wikipedia state that "Babylonian astronomers [place] the beginning of Aquarius at the "Rear Star of the Goat-Fish" (δ Capricorni)?" Do they simply mean the end of Aquarius?

And why do I have to set the date to December 21, 8000 BC to get the sun between Pisces and Aquarius?

An interesting couple of questions.
I think the first point is trying so say that although the classical zodiac constellations were based on the
position of the Sun against the equator (i.e. the rising node where the Sun crosses the equator); the Babylonians used specific stars to demarcate the starting positions of the zodiac constellations.
As the Sun moves through the constellations, it passes through Capricorn before it passes through Aquarius, so I assume that is when the Sun passes δ Cap it marks the start of its passage though Aquarius.

As for the second question; on the basis of this, I would assume that Aquarius was probably unrelated to the position of the equinox, so if the equinox was in that region 5500 years earlier, it's probably incidental.
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Re: vernal equinox/Zodiac

Postby The Man with the Corrugated Iron Roof » Sat Sep 09, 2017 9:09 pm

We Ophiuchans do not believe in astrology either!

I would expect the ascending node (intersection of ecliptic and equator) to have been in Hydra in 8000BC.
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