Skyscript Astrology Forum

Deb wrote:I think there's enough evidence via various texts for us to be confident that older sources recognised the equinox as falling in the middle of the signs, so that the signs were divided by it. By Ptolemy's time precession had brought the equinox from the middle of sidereal Aries to the beginning of Aries, and at the time Ptolemy makes it clear that wherever the equinox falls, that point will be 0? Aries. Are we in agreement that, in either of these ancient approaches, the motivation was to have a zodiac that identified the equinoxes and solstice points?

I'm not sure I could agree that that was the motivation, but perhaps that is because I'm not entirely sure what we're talking about (the motivation behind what?). Ancient astronomers/astrologers were interested in identifying these points, but that's not all they were interested in, and I think the fact that the points are placed at 15? or 10? or 8? or 0? at different epochs shows that they had another framework in mind -- namely, a sidereally defined zodiac -- that took some sort of conceptual precedence.

Re straight and crooked - Dorotheus uses this, but I'm assuming you know about that. If not, I'll provide a ref.

Yes, I know about it from the literature; I meant I hadn't seen anyone now living actually use it in his or her work. I'm sure some people do; it's just not on the top-10 list of most astrologers' considerations -- I think.

Paul wrote:I think to be more precise, they [antiscia] are only connected via the declination of one body alone - the sun. Two planets on the same declination are not necessarily going to be at the antiscia of each other.

Yes, I was just talking about points on the ecliptic (which, of course, is the path of the Sun), without reference to the planets. When you start looking at planets' declinations, then their latitudes from the ecliptic will obviously mean that positions by longitude are not enough to determine a true antiscion relationship. That's why both Morin and Placidus (much as they disagreed on other matters) advocated using what Placidus preferred to call parallels of declination based on the planets' true positions, including latitude.

jventura wrote:In other words, could we say that sidereal astrology, in a practical point of view (which is what matters to the computer, zeros and ones), is the same as tropical astrology + offset of signs? Or there are more practical differences?

Because of the shift caused by precession, the timing of events (e.g. transits, progressions...) is different in sidereal astrology. This difference is relatively small in the span of a lifetime, but becomes increasingly significant in mundane astrology or in precise natal work and synastry.

There is in my view a lot of confusion on this matter because many sidereal astrologers continue using tropical time units (accumulating a difference of 4 minutes of time per day), thus mixing two different reference frames.

An example is the elimination of the "bija" correction among Fagan siderealists. Another example is the calculation of the time of sidereal solar returns while drawing the corresponding chart tropically (the so-called "precession-corrected" charts), or using sidereal returns but working with tropical transits and progressions, therefore limiting the label "sidereal" to representing in a sidereal zodiac a strictly tropical calculation.

Because astrologers tend to follow tradition or standard practice instead of astronomical or mathematical consistency, I personally think the use of a sidereal reference frame for the calculation of time-space planetary coordinates is generally-speaking poorly understood and applied.

So perhaps the first thing one has to clarify when using the label "sidereal" is whether one means standard (classical or modern) sidereal astrological practice, or working strictly under "a sidereal reference frame". The two are often not the same thing.

Juan

Juan wrote:There is in my view a lot of confusion on this matter because many sidereal astrologers continue using tropical time units (accumulating a difference of 4 minutes of time per day), thus mixing two different reference frames.

I'm afraid you're muddying the waters here. Astrologers have reckoned days from sunrise to sunrise since long before the tropical zodiac became popular; the two issues are not related. Sidereal astrology is not about disregarding natural astronomical cycles. The question is simply this: given that the zodiac cannot remain fixed with respect both to the constellations and to the seasons (a fact that was not clear to many of the ancient writers), which is more important? If you think the constellations take precedence, then you're a siderealist. It's just to do with the location of 0? Aries on the ecliptic -- that's all of it. No need to switch from solar to sidereal days, etc.

I do agree about the inconsistency involved in using precession-corrected charts drawn in a tropical zodiac, though.

Juan wrote: There is in my view a lot of confusion on this matter because many sidereal astrologers continue using tropical time units (accumulating a difference of 4 minutes of time per day), thus mixing two different reference frames.

Juan

I have to disagree with this. Sidereal astrologers are typically how we refer to people who hold one particular view: that particular significance of the ecliptic is derived from equal divisions of star patterns. This is essentially the sidereal claim. What isn't the sidereal claim is that in order to be a sidereal astrologer, one most posit all frames of reference of either divisions of time or of space from a fixed star.

Likewise, for contrast, tropical astrologers don't say that the only frames of reference that can be used are tropical/seasonal/solar - in other words it's okay for tropical astrologers to utilise, say, sidereal time in their calculations for various celestial or astronomical phenomena.

Of course we could, if we wished, break open the words "sidereal astrologer" and decide that we wish to imagine that this must mean that sidereal astrologers should not just derive meaning from constellations, but also that they should restrict all measurements of time or space (ie, divisions of what constitutes either a day or a year or the ecliptic etc) by stars as well. This is not what sidereal astrologers, as we commonly understand the term, themselves claim, if we wish to re-describe what "sidereal astrologer" may mean, then any criticisms we have of sidereal astrologers only become criticisms of our definition instead.

So in other words, what we refer to as tropical or sidereal astrologers are people who put their focus on divisions of the ecliptic from which meaning or significance can be derived, but just do so in different ways, or, rather do so according to different premises.

So one can still be a tropical astrologer and utilise sidereal time for whatever calculation purpose he/she needs. Similarly one can still utilise a solar year without claiming to be a tropical astrologer. Because in both those instances we're measuring time divisions which need not be related to a division of the ecliptic. If anything we might argue these are divisions of the equator.

So I also disagree with both yourself and Martin therefore with regards precession correction, because actually it's the same logic. If we consider how we might define a sidereal day, for example, we could easily state that it's the apparent return of the position of the Sun by primary motion to the same position in space it occupied after a rotation of the earth. Now, as it happens, how we measure that could be, say, by measuring the length of time it takes a fixed star to culminate in one day and culminate in the next day. And this time would be 4 minutes less than 24 hours.

But notice that we're not claiming that the stars themselves are what determine a sidereal day, it is not because of some stellar influence or stellar symbolism which causes (or insert a better word) the rotation of the earth to be almost but not quite 24 hours. The stars are merely a convenient measuring stick. This is distinct then from the notion of a sidereal zodiac in which the stars are not merely a measuring device, but also that significance is derived from them.

Let's expand the analogy to a given year. We can likewise measure the return of the position of the Sun, in space, in a given year. The difference between this and the tropical/solar year will be incredibly small but the logic is the same, we're not determining the significance of some star when we measure the year sidereally any more than when we measure the day sidereally. We're simply using the stars as a convenient tool from which we can measure - conceptually though the stars themselves are not significant to either the rotation of the earth in a day, nor the revolution of the earth/sun in a year.

So precession correcting a chart is not therefore mixing tropical astrology with sidereal astrology, rather it's measuring what the meaning of a 'return' means - whether it means a return to the same position in the ecliptic, or a return to the same position in space. It is not, for example, determining significance or meaning from a sidereal framework, but, rather, simply using the stars as a convenient tool to determine sidereal years, which, as per my previous arguments, really is nothing more than a convenience.

Precession correction then is something of a red herring at times, as it can imply to astrologers that we're applying precession to the zodiac, like we do with an ayanamsha, but in fact really we're just taking the sidereal year, which, really, has nothing to do with stars except being a useful measuring device.

Now personally I don't actually use precession corrected solar returns so I'm just really playing devil's advocate here. I have seen other astrologers, however, use them well though and I wanted to clarify their argument about what they're actually doing with precession correction.

Martin Gansten wrote:I'm afraid you're muddying the waters here.... Astrologers have reckoned days from sunrise to sunrise since long before the tropical zodiac became popular; the two issues are not related. Sidereal astrology is not about disregarding natural astronomical cycles.

Since when the return of a fixed star to the same position with respect to the horizon or the meridian it had the day before (i.e. the sidereal day) is not a natural cycle?

You are missing the point about the concept of a "reference frame". Either you measure time with respect to solar phenomena like the seasons, or the solar day --the tropical approach-- or with respect to fixed fiducials in the night sky --the Babylonian sidereal approach. If we choose to use the night sky instead of the Sun as a measuring stick, we should do it with respect to time as well as space.

Your response illustrates my point about tradition vs mathematical or astronomical consistency.

I do agree about the inconsistency involved in using precession-corrected charts drawn in a tropical zodiac, though.

The usual practice is the result of artificially separating time and space. The time of the chart is calculated correctly, but the precessional shift from the time of birth is ignored. When the sidereal fiducial is assumed to be the time of birth and the necessary and small precessional displacement is subtracted from the return positions, the result is a well-defined and consistent sidereal chart.

The main point about "sidereal vs tropical" --when seen astronomically-- is not about using any of the traditional sidereal zodiacs but about establishing an arbitrary "epoch" or "fixed" time/space fiducial from which to measure a precessional displacement. No constellations or individual fixed stars need to be involved.

Juan

Paul wrote:What isn't the sidereal claim is that in order to be a sidereal astrologer, one most posit all frames of reference of either divisions of time or of space from a fixed star.

That's fine when the "sidereal" label is defined in terms of traditional practice. It doesn't change the fact that in this practice there tends to be a mixture of reference frames. And viceversa: when the "sidereal" label is applied astronomically as a reference frame, the traditional practice is left behind and you begin to use new concepts such as sidereal right ascensions or disregard the zodiacal subdivisions entirely.

The stars are merely a convenient measuring stick. This is distinct then from the notion of a sidereal zodiac in which the stars are not merely a measuring device, but also that significance is derived from them.

For a zodiac to be "sidereal" (even in the traditional sense) all is needed is that its starting point be considered "fixed" in time an space, and --for calculation purposes-- precession be calculated from that point; it has nothing to do with zodiacal subdivisions or the prime importance of a fiducial star.

So precession correcting a chart is not therefore mixing tropical astrology with sidereal astrology, rather it's measuring what the meaning of a 'return' means - whether it means a return to the same position in the ecliptic, or a return to the same position in space. It is not, for example, determining significance or meaning from a sidereal framework, but, rather, simply using the stars as a convenient tool to determine sidereal years, which, as per my previous arguments, really is nothing more than a convenience.

I think we're on the same track here. To clarify from my first post (please see my previous one) the mixing of sidereal and tropical that I mentioned refers to the common practice in popular astrological software of calculating the time of the return sidereally but drawing the chart tropically, and mislabelling this "precession-corrected tropical". A simple precession-correction of 50" per year from birth that equates the return Sun to the natal Sun is all that is needed to make the chart truly sidereal, or truly "precession-corrected". A traditional sidereal zodiac is not needed.

In terms of the original practical question by Jo?o, "working sidereally" can be seen either as following sidereal astrological tradition or working in a sidereal reference frame. I think it is important to understand the differences between the two, and account for the fact that "sidereal" or "precession" is not just about the subdivisions of space, that there is also a difference in the timing of all astrological events that involve a comparison between two dates.

Juan

Juan wrote:For a zodiac to be "sidereal" (even in the traditional sense) all is needed is that its starting point be considered "fixed" in time an space, and --for calculation purposes-- precession be calculated from that point; it has nothing to do with zodiacal subdivisions or the prime importance of a fiducial star.

(emphasis mine)

Well I'm not sure about that. Certainly that's true in terms of calculation, we just need to know where a fixed point of the zodiac is, and where in the zodiac it is, and we can calculate the rest of the sidereal zodiac - this is pretty much how we calculate it anyway. But that emphasis on calculation removes the ethos of why we're calculating it in the first place. I'm a tropical astrologer so sidereal astrologers here I'm sure do not need me to defend their zodiac, but when we focus so much purely on mechanics of calculation, we lose perspective on the ethos of the sidereal zodiac itself, which is really more to do with defining significance from the constellations which roughly overlap the signs of the same name. So the sidereal zodiac is a measuring device, but not just a measuring device, it also can be said to have significance so that a planet or point found in a sector of the ecliptic, as defined from star patterns, actually has meaning. Deriving meaning from the stars is therefore the key trait of the sidereal zodiac and of sidereal astrologers. In contrast, being able to measure from a fiducial point is not the key defining feature.

I think that focus is lost in the part of your quote I've emboldened above. This is the main difference then between measuring a day or a year or several years using a sidereal frame of reference against being a sidereal astrologer, because one is merely a measuring device, and the other is not just a measuring device but the idea that meaning or significance is derived from divisions of that measurement.

To clarify from my first post (please see my previous one) the mixing of sidereal and tropical that I mentioned refers to the common practice in popular astrological software of calculating the time of the return sidereally but drawing the chart tropically, and mislabelling this "precession-corrected tropical". A simple precession-correction of 50" per year from birth that equates the return Sun to the natal Sun is all that is needed to make the chart truly sidereal, or truly "precession-corrected". A traditional sidereal zodiac is not needed.

Right, but I think we should focus more on what they're doing or what they're attempting to do rather than how exactly they're doing it. What they're really doing, in the case of a solar return, is position the sun at the same place it was at birth. But we can do this in more than one way. We can reference 'return' in terms of its relative position to our given zodiac, or we can reference return as being a return to its position in space (or, rather, earth's position in space, but let's imagine it's the same thing), and then project that position onto our zodiac.

One can still be a tropical astrologer, believe that the tropical zodiac is where we can derive meaning, but still choose to understand the word return as being a return to its position in space, and map that position in space onto our zodiac.

Now how software programs choose to this is less important - software developers may elect to choose all kinds of time saving approaches, or, more likely, choose an approach which requires either less development time or even better less development changes. Typically in software development, changes are an opportunity to introduce bugs. Whilst there are many patterns that developers employ (or should employ) to reduce this risk, not everything which could be in scope was conceived of when a project first started and if someone was to employ every way of reducing bugs from change, no software would ever in reality get developed. And so a software developer may realise that they can get the same result with fewer changes by utilising features or functionality pre-existing in the software, or extending them in certain ways.

So if it becomes relatively trivial to translate to a sidereal zodiac and then utilise this time and translate it back to a tropical perspective, then why not do this? Ultimately the program is only being used as a labour saving way to create the chart and the positions in the first place. The point will be that those tropical astrologers using a precession-corrected solar return (and the name lends itself to creating this confusion) will know that they're still, philosophically, deriving meaning from the tropical signs, but measuring time not necessarily from a solar year.

But we must accept that measuring time or using time based frames of reference is entirely distinct from defining meaning from ecliptic divisions.

In terms of the original practical question by Jo?o, "working sidereally" can be seen either as following sidereal astrological tradition or working in a sidereal reference frame.

I agree, but we should also accept that as astrologers with a technical vocabulary of distinct meanings, when we say sidereal we typically mean by that, by convention, astrologers who utilise a sidereal zodiac, by which we mean astrologers who posit that the constellations are pregnant with significance/meaning. By convention, what we don't mean, is someone who is limited to always measure time or space sidereally and in no other way.

If your post is just to highlight that tropical and sidereal astrologers utilise sidereal or tropical frames of measuring time for varying purposes, well I agree. But it seems to be more an attempt to suggest that it's inconsistent to do so, and it's here I would disagree.

Paul wrote:when we focus so much purely on mechanics of calculation, we lose perspective on the ethos of the sidereal zodiac itself, which is really more to do with defining significance from the constellations which roughly overlap the signs of the same name.

What you call "mechanics of calculation" is not independent or separate from a cultural world-view, specially in the ancient world, and particularly --in this case-- in Babylonian astronomy and astrology, which as you know were not separate things. The alleged primacy of the zodiacal subdivisions and meaning derived from them is the result of using the night sky as the fundamental reference frame. The night-sky and the location in it of a zero point is the sidereal paradigm, not the zodiacal subdivisions, which are a secondary layer and --as illustrated in modern practice by many Fagan siderealists-- can be completely ignored in practice.

Keep in mind that the Babylonians used sidereal time measurements or fiducials and consistently rejected the use of the tropical ones:

"Babylonian astronomy is based exclusively on the sidereal year and on the two zero points mentioned, which are determined sidereally. This, however, does not exclude the possibility that Babylonian astronomers knew the tropical year. They only never used it in their computations and ephemerides, and they never abolished their sidereal zero points in favour of the true vernal point [...]
"In sum, it cannot be doubted that the Babylonians of the late sixth century were perfectly familiar with the difference between the tropical and the sidereal year-lengths. This is not at variance with the fact that tropical year plays no part whatsoever in their ephemerides, goal-year texts, etc. There is no lack of plausible reasons for this apparent contradiction. Among them the most prominent may have been that they regarded the starred firmament as the only natural system of reference, on which planetary positions could be read directly."

Willy Hartner "The Young Avestan and Babylonian Calendars and the Antecedents of Precession", Journal for the History of Astronomy x (1979).

Juan wrote: What you call "mechanics of calculation" is not independent or separate from a cultural world-view, specially in the ancient world,

No, but then I'm not suggesting it's independent or separate, only that by focusing on it to the level of the post I highlighted we can lose sight of what the major claim of sidereal astrologers actually is, and that claim isn't "one must use a sidereal frame of reference to the exclusion of all others for the purposes of measuring something". It's that the constellations or the sidereal backdrop as a whole is pregnant with symbolism and meaning and that this meaning can be extrapolated from them.

I honestly think if we sum up the major focus of the sidereal perspective as being simply using a fidcuial point and safely ignore divisions of the ecliptic, that really we lose sight of what the majority of sidereal astrologers actually believe and we fool ourselves into thinking that using any sidereal frame of reference makes someone a "sidereal astrologer". By this reckoning anyone who utilises sidereal time anywhere in any astrological calculation is a sidereal astrologer - that doesn't capture what we typically mean by the distinction sidereal astrologer, as opposed, say, to tropical astrologer.

It is not enough to say that a sidereal astrologer is someone who measures from a fiducial point, fixed in time and space. The focus is not just on a fixed star, and then after that who cares, the major concern is that meaning can be extrapolated from the signs which are related to constellations.

If we focus purely on the mechanics of how to calculate the zodiac (a fiducial point) it doesn't tell us anything about the ethos or spirit of sidereal astrologers and their beliefs - I'd be interested in hearing from sidereal astrologers on this though. This is my understanding.

The night-sky and the location in it of a zero point is the sidereal paradigm, not the zodiacal subdivisions, which are a secondary layer and --as illustrated in modern practice by many Fagan siderealists-- can be completely ignored in practice.

Well I guess I disagree with this. I am not sure what practice many Fagan siderealists do - I am not a sidereal astrologer myself. I mean at least let's accept that it's not merely a location of a zero point. I think we lose the spirit of sidereal astrology here. For me, sidereal astrology is not just using some fiducial point, but rather, like with tropical astrology, an attempt to measure the ecliptic and recognise meaning that can be derived from it. With sidereal astrology that meaning is derived not from one fixed star in time and space, but rather the whole stellar backdrop.

Willy Hartner "The Young Avestan and Babylonian Calendars and the Antecedents of Precession", Journal for the History of Astronomy x (1979).

I'm not sure how this quote precludes or contradicts anything I'm saying though, as I note it's a commentary on how the Babylonians measured time.

If the Babylonians measured the year from a sidereal perspective, whilst interesting, doesn't inform us much about the subject under discussion here. After all, sidereal astrologers today use a tropical/solar year, but that doesn't make them tropical astrologers, as, to keep with my point, they're not deriving zodiacal meaning from the tropical year.

Otherwise everyone is a sidereal and a tropical astrologer because everyone when calculating various celestial phenomena may need to know sidereal time as well as tropical considerations. And if everybody is everything, then the distinctions become meaningless.

Juan wrote:Since when the return of a fixed star to the same position with respect to the horizon or the meridian it had the day before (i.e. the sidereal day) is not a natural cycle?

I never said it wasn't. It just isn't the only kind, and as Paul has already pointed out, there is no reason (logical or otherwise) to limit yourself to one kind, except when they contradict each other.

You are missing the point about the concept of a "reference frame".

Nope. I just reserve the right to use more than one, as astrologers have always done.