Method by which the Koch Houses are calculated.

Hello there!

I am looking for the exact method by which the Koch house cusps are being calculated.

My goal is to create a function so I can easily see when my own houses are conjunct those of the current transiting houses.

The thing that's keeping me from doing that is that I can't seem to find a mathematical explanation about the Koch method, only people discussing it.

Can anyone of you here show me the right direction? Maybe you even have some experience with what I am trying to do.
If you know of some software which is capable of doing just that (checking house cusp aspects) that would be good too!

Hello,
Most software calculate them, but you can actually calculate them with a Placidus table of houses by doing the following. If you don't have access to one, at least this explanation will help you see how they're formulated. I'm not aware of any software that calculates aspects to cusps in any system.

Start with the chart you want to calculate Koch houses for. Note the degree of the Midheaven. You're going to move this point through equal periods of its diurnal arc and note the resultant Ascendants. For the latitude of the chart, find the time when that Midheaven degree was the Ascendant - this is when the Midheaven degree rose. Now, using the Placidus table of houses, find the time when that Midheaven degree rises up to the twelfth cusp - the Ascendant at that time is the Koch 11th house cusp. Next, find the time with that Midheaven degree is on the eleventh Placidus cusp - the Ascendant at that time is the 12th house cusp for your chart. Of course, when you find the time for that Midheaven degree is on the 10th cusp, you'll realize that you have your first house cusp which you already knew about. You can continue this process until that Midheaven degree sets.

So, basically, with the Koch cusps you are noting what the Ascendant is as you move the Midheaven through equal periods of the earth's rotation at a specific latitude. Since Placidus cusps reflect equal periods of rotation by definition, noting when the Midheaven is on those cusps you can see what the Ascendants are, and those Ascendants are Koch cusps. However, if your chart is a polar chart you will not be able to calculate Koch cusps if the Midheaven degree was circumpolar, that is, if it never is an Ascendant at that latitude. There is also an issue with planets being in the 9th and 10th houses simultaneously (or the 3rd and 4th) sometimes. If you go to astro.com and run charts in the "Fixed Stars" chart you'll see that happening. Personally, because of these issues, I'm uncomfortable using Koch.

I hope this explanation made sense!

Drsendero

Hi Vahntaar

You might find The Elements of House Division, by Ralph Holden, useful. You can get it cheap second hand on Amazon, etc.

Best wishes

Miquar

You can purchase a Koch table of houses from amazon. Once you complete the mathematics for the B.T. given your end result is the R.A.M.C. or right ascension of the mid heaven. This figure is then sought out in the Koch tables. You then calculate the (birth ST minus lesser ST) divided by (Greater ST minus lesser ST) equals your longitude constant.
You now take (greater MC minus lesser MC) times longitude constant equals, then plus lesser MC equals corrected MC
After this you start on your double interpolation of the remaining cusp lines according to lesser and greater latitudes