quotidian calculations

[Freya]

May 24, 2013
Does anyone know how to calculate a quotidian by hand? I would like to learn how to do this.
Any help would be very much appreciated. Thanks

[Freya]

NQ? SQ? PSSR? Other?
Oh, I know.
All of the above.

[Freya]

The mean quotidian. In how does it differ from secondary progressions?

[Freya]

Rummaging through my books to find a calculation method not based on Besselian Time, which is no longer used..

[Freya]

I think the difference is semantics. In other words, the mean quotidian is the same as the Q2. But I could be wrong, because... semantics.

ETA: That was helpful...not.

The Q1 is secondary progressions based on a year figured in sidereal time.
The Q2 is secondary progressions based on a year figured in mean civil time.
The Q2 is the mean quotidian.

[Freya]

Thank you very much....which one is more accurate?

[Freya]

I found an old book written by one James Arthur Eshelman in 1975, called The Sidereal Handbook An outline of Sidereal Methods.
It uses Besselian time, which I believe we no longer do.

But I think you can just substitute Julian time for it.
If you're computing for midnight (or noon if you use a noon ephemeris) you can use the Julian date from the ephemeris. Otherwise, interpolate for the time you want.
Subtract the Julian date of birth. Count the years as days. So 23 years would be 23 days.

EDIT: Ignore the above. Compute the Right Ascension of the Mean Sun (RAMS) for the date and time for which you want your chart. You should have RAMC for your birth chart.

Add 5 hours 20 minutes to both RAMCs, subtracting 24 if it comes out over 24 hours and convert to a fraction of 24h. Your BT is the year followed by the fraction. So May 24, 2013 at 6:16:13 PM CST would be RA 05:54:40 so 2013.2462963. More or less.

Subtract the BT of birth from the BT of the date and time for which you want the chart.

Add the Universal Time (UT) of birth.
EDIT Add the UT and DATE of birth.

That's the date and UT of your quotidian.

Somebody please check and make sure I got this right!

[Freya]

The Q2 is more accurate, I believe. Pretty sure here. That's what I gave the calculation method for.

[Freya]

Sorry. I spent an hour writing an anser, then hit a wrong keystroke and deleted most of it. I don't have another hour to recreate the number trail (I have 50 hours of lecture material to prepare in the next five hours). If you get my out-of-print book The Sidereal Handbook (usually available through Amazon), it explains how.

[Freya]

Can we just substitute Julian date for Besselian date?

And be reasonably accurate?

[Freya]

Freya, are we telepathically connected? Often, when you bring up a topic, I'm also thinking about making a post about it.

I mistrust how software packages compute progressions. I think that the progression module in those that I've seen (all two or three of them ) is fundamentally flawed or inadequate in their design.

I have built up my own custom spreadsheet program for calculating progressions.

So first, Freya (and everyone interested), do you have a spreadsheet? I recommend Open Office over any Microsoft version because 1) it handles dates before 1900 (and MS cannot), 2) it correctly identifies 1900 as a regular year (whereas MS incorrectly makes it a leap year), and 3) it's FREE! (whereas MS costs an arm and a leg). (A note: I do not know whether the functional criticisms apply to the current MS spreadsheet, since I have not used it.)

http://www.openoffice.org/

Mr. E., if you ever have the time to reconstruct your lost reply, even piecemeal, I'm sure it would be valuable.

-Derek

[Freya]

Sorry. I spent an hour writing an anser, then hit a wrong keystroke and deleted most of it.

Oh, No!!

Derek is right, I don't trust softwares either. I have two of them, and they have come up with different calculation for the Q2 Midheaven.
Yes, I have a spreadsheet from openoffice

[Freya]

Chances are, one is giving Q1 (based on the difference in sidereal time, often using the BIJA correction which is now depreciated) and others are giving the Q2, (based on the difference in mean solar time or the civil day which is the same thing.)

Which software packages are you using and what dates and times are the giving for a specific day. We should be able to work backwards to figure out who is using what, and choose a better software package based on that.

[Freya]

Can we just substitute Julian date for Besselian date?

And be reasonably accurate?

I am about to upload a short version of a spreadsheet I've developed over the years doing just that! Looking over the old material for calculating progressions, they are in serious need of updating!!!

That's not to say that the old methods need to be discarded. I recommend at least competency in using them to check your results and in case of computer failure.

-Derek

[Freya]

Thank you very much Derek.

Ok, here are the details, without disclosing the software names so far, let's just look at the maths

My birth details are July 6th 1984, Florence, Italy. I currently live in Andover, Hampshire, UK.
The quotidian calculated is for May 25th 2013, in Andover at 1:50:44 AM BST -1:00

Software A gives the MC at 10 TA 30

Software B gives the MC for 10 TA 55

are they both incorrect?

[Freya]

Here is a short version of a progression calculator I've developed. For the example, I've used Susan Walker from "Primer of Sidereal Astrology" for a fast comparison of the Q1 and Q2 results.

First, some notes on using it.

The Sheet named "VALUES" holds the units providing flexibility in calculations. If you want to use the Sidereal Day, the Civil Day, tropical or sidereal months or years, their values are located here. Since the "Sidereal Day" is misnamed and is really a "Tropical Day" I have included the values for the Inertial Day which is the true sidereal day. (Fagan was aware of this unit, but I don't have the exact reference at hand.) Unless you know what you're doing, don't change anything here.

The Sheet named "SELECT TIME UNITS" is where you do just that. Put the cursor in each cell on row 4 to get a drop-down box and select your values. The notes in rows 16-18 are there to remind you what's what (and they are sufficiently far down that they are not obscured by the drop-down box). Typically, you will want to keep it set to Sidereal Month, Sidereal Year, and switch between Civil Day for Q2 and Sidereal Day for Q1.

The Sheet named "PROGRESSIONS" is where you input the natal data and the target date/time, and get the output progression dates.

Cells I2:K4 remind you what units are active.

Cells A3:D4 are the basic data input. Please note that it is not sophisticated enough to convert different time zones, so be aware and put both natal and event time zones on the same basis.

The ultimate results are under "PROGRESSED DATE." These dates and times are what you should use for new input in your preferred astrology program (again, be mindful of any time zone issues).

[Before changing any birth data, switch between Sidereal and Civil days and look at cell H12; compare with page 33 of the Primer. You will see that when using Civil Day, the Progressed Interval agrees with the Primer's "Uncorrected age of native in days, etc." When using Sidereal Day, the Progressed Interval agrees with the Primer's "Native's corrected age."]

The COMMENTS on the far right should be helpful in keeping track of what you're getting.

There's other information, should you choose to use it. "SF RATIO" is the value to put into Solar Fire (or other program) for a custom progression rate.

"PROGRESSED INTERVAL" explicitly shows the progressed age. This is what's added to the natal date/time to get the progressed date/time.

The "REAL TIME" column may seem mysterious but makes sense in the more elaborate version, which I am not prepared to discuss now. You may ignore it for now.

In the Tertiary Progressions row (row 13) the Sidereal Time result will differ from what would be gotten from Bradley's article on Tertiaries because ... well, I'll put it plainly, that Sidereal Time calculation actually belongs to yet another progression rate. It's as intimately related to Tertiaries (as calculated here) as Primaries are to Secondaries. But for the time being, I don't want to get into that; it makes even my head spin (still).

-Derek

[Freya]

Thank you DereK

You're quite welcome. If you have any questions, please ask.

-Derek

[Freya]

I have just looke at the file....all I can say is WOW!! Kudos, Derek, it's really well done. You must have spent a lot of time creating this document... thank you for sharing it.

[Freya]

I edited my post above with instructions on how to use Besselian Time instead of Julian Date because I think it's easier to get the RA of the MS and compute from there. Not necessarily more accurate, but easier.

Since our zodiacal measurements may be off by a few seconds, I think we can get close enough figuring BT by hand even if Julian Dates might be more accurate. And there's the fact I understand BT but not Julian Dates. I used to understand both, but that was 40 years ago.

[Freya]

Very Nice, Derek.

Off to play with it.

Thanks.

[Freya]

Can we just substitute Julian date for Besselian date?

And be reasonably accurate?

You are presuming she understands those terms at all. I spent most of an hour explaining how to use an ephemeris to extract the RAMS. Jumping to BT is probably an unnecessary complication, provided you remember that the RAMS year begins at the northern hemisphere vernal equinox.

[Freya]

My first message started out "First you need an Ephemeris." but I decided that was a bit too basic and if someone has an ephemeris it was likely they'd know some basics about casting a chart from it.

[Freya]

I have just looke at the file....all I can say is WOW!! Kudos, Derek, it's really well done. You must have spent a lot of time creating this document... thank you for sharing it.

I blush. Yeah, I spent time on and off over the years, with various levels of concentration. I figure it's good enough, but there's a lot to be desired.

Eventually, I expect to introduce the more elaborate version when I've got it together to discuss the concepts (Mr. E willing).

-Derek

[Freya]

Yes, I think I understand the difference between the Besselian and Julian epoch.
Cyril Fagan explains how to calculate quotidians in Primer of Sidereal Astrology, is his method still valid?

[Freya]

Yes, I think I understand the difference between the Besselian and Julian epoch.

Before computers such as we have now, even in the 1970s period when calculators ruled the scene, the main problem was dealing with the fact that the integer count of days in the calendar year don't fit neatly into the fractional length of astronomical years. The fact that leap days, when they occur, are placed oddly within the year (putting it at the end would be neater) created the potential for wrong calculations. Hence such makeshifts as starting the year on March 1, which creates potential mistakes if the year weren't correctly accounted for.

Besselian time is another makeshift. Since the Mean Sun is at 18:40 around January 1, just start from that point, call it 00:00 and proceed from there - that is, add 5:20 and subtract 24:00 as necessary. This way, it's hard to mess up on counting elapsed years and whether or not there's a leap day is irrelevant. Besselian time is notated in Right Ascension of the Mean Sun in time. I've never seen it presented in degrees.

There are several schemes going under the rubric of "Julian Day." The first and authentic version has a definite beginning date and is purely and simply a count of days, no years, no months. In modern times, that number is unwieldy, so often it is truncated to relevant digits, with a note about the large number to be added to it. Another version is simply the day of the year from January 1.

Cyril Fagan explains how to calculate quotidians in Primer of Sidereal Astrology, is his method still valid?

Yes, the method gives the Q1 and is still valid, but is geared to the fact that astrologers of that time had to use pencil and paper, which made tables such as in the Primer necessary shortcuts.

For example, trigonometric values can be gotten from a calculator with a few keystrokes, or in a computer program with the proper function. The machine is calculating every value from scratch every time. Time was, whole books were published with trigonometric values, because looking them up in a table was quite simply the easiest way to get them.

-Derek

[Freya]

Thank you Derek for your very clear explanation

[Freya]

Add 5 hours 20 minutes to both RAMCs

can you please explain how you arrived at 5 hours and 20 minutes? Thanks

[Freya]

Add 5 hours 20 minutes to both RAMCs

can you please explain how you arrived at 5 hours and 20 minutes? Thanks

I'm sure Jupiter Sets at Dawn meant to add 5:20 to the RAMS, Right Ascension of the Mean Sun. JS@D is describing how to compute Besselian Time natally and for the time in question. Once that typo is understood, the rest falls in place.

-Derek

[Freya]

thank you Derek, now it makes sense
Is this the exact calculation written in The Sidereal Handbook? I am asking because the copy available on amazon is too expnesive for me to buy at this time.

[Freya]

FINDING THE MEAN SUN WITH SOLAR FIRE

Go to Dynamic > Ephemeris generator.

Under the section Period of Ephemeris, select a reasonably short period of time, such as 5 days, that includes the date for which you're calculating and the day after. For "Start Time", be sure to enter 12:00. That's important.

Frequency of Entries: Every 1 Day.

Ephemeris Time Zone: You can use your own time zone for convenience, but to double-check your results, I recommend GMT so you can cross-compare your results with a noon ephemeris. When you feel comfortable, you can switch to your own time zone. That's one of the flexibilities that gives computer programs such as SF an advantage over print media.

Zodiac: Fagan-Allen
Coordinates: Geocentric
Lunar Node: Your choice. It's not relevant here.
Items to list: It's important to tick "Sidereal Time." SF seems to require at least one real planet so tick "Right Ascension" as well. Let's keep it simple for now and untick the other options.
Points to list: "Transiting Chart Points:" Use whatever you want, but for this exercise stay simple and create a point chart that consists of only the Sun. By this time, you've set up the ephemeris generator to show the RA of both the Mean Sun and the transiting Sun.
Precision: Your choice, but in this instance I prefer "Seconds of Arc." It won't affect the Sidereal Time, but it will affect the Sun and any other planets you're choosing to list.
Notation: Zodiacal. (or "Decimal Degs" if you're comfortable with it.)

Start the ephemeris generator. The Sidereal Time is identical with the Right Ascension of the Mean Sun. Since you've included the Sun as a point, you also have the RA of the transiting Sun for work requiring that.

Interpolate by usual means for the desired time, keeping in mind that you are figuring from noon, not midnight.

FOR MORE ADVANCED USERS

Set the Frequency of Entries to 1 Hour.

For every hour after 12:00, subtract an hour from the Sidereal Time. For example, 13:00 is one hour after 12:00, so subtract one hour from Sidereal Time. For 03:00 (that's AM), it's 15:00 after 12:00, so subtract fifteen hours from Sidereal Time. Your results should show a smooth advance of 0:00:10 (sometimes 00:00:09) per hour from the noon position.

-Derek

[Freya]

So May 24, 2013 at 6:16:13 PM CST would be RA 05:54:40 so 2013.2462963.

Let's check this!

Go to Solar Fire's Ephemeris Generator.

Start date: May 24, 2013. Start Time: 12:00:00.
End date: May 25, 2013. End Time 12:00.
Frequency of Entries: 1 Hour.

Start the Ephemeris.

Add 6 hours to 18:00 CST to find that it is equivalent to 00:00 the next day. In the ephemeris, go to May 25 2013 00:00. The RA of the Mean Sun is 16:10:57 - 12:00:00 = 04:10:57. Since you can see that that the RAMS is advancing 10 seconds per hour, and that this is 1 second per 6 minutes, and you can round 0:16:13 to 18 minutes, so you add 3 more seconds to get 04:11:00. [You can use a table for this part, if you don't want to engage your brain just a little.] Add 5:20:00 to that and the result is a Besselian Time of 2013 09:31:00.

Compare that to The American Sidereal Ephemeris. At midnight on May 25, 2013 the RAMC is 16:10:58. By happy coincidence, this is already close to our target time. Subtract 12 hours (you can visualize this as the Mean Sun being on the IC instead of on the MC) add the requisite 3 seconds and you get RAMS of 04:11:01, in essential agreement with the prior results.

-Derek

[Freya]

Thanks Derek, that was very helpful.
Have you (or anyone on this forum) got any experience with the regressed solar quotidian? Is it worth looking into?

[pjef]

Here is a short version of a progression calculator I've developed. For the example, I've used Susan Walker from "Primer of Sidereal Astrology" for a fast comparison of the Q1 and Q2 results.

This was from a few years ago. Was this spreadsheet ever uploaded onto this site? I would love to have a copy of it.

Thank you in advance for any information.
Patti

[Jim Eshelman]

It is very Wonder for quotidian calculations. I would like to calculate

Youldiz, do you have a specific question?