Now here's a dandy celestial mechanics problem for you. Given the elliptical orbit position of Mars and Venus in one individual's natal chart, graph the solution set of all possible Mars-Venus positions that will result in Mars-Venus conjunction in the Davison chart.
Sound like absolute gibberish to you? It won't if you are somewhat familiar with astronomy of astrology. You know that the bodies of our solar system orbit the sun according to an eliptical pattern, ergo it is possible to determin their location at any given time. Conversely, it possible to determine the calandar date and time when they will reach precisely these positions. This is just about perfectly predictable, celestial mechanics being what they are.
The Davison Harmonic means chart simply takes the position of two natal chart bodies (his Mars and her Mars) and averages them together. If his Mars is at 180 degrees (00 Libra) and her Mars is 00 degress (00 Aries) together they wind up at 90 degrees (00 Cancer). That's it folks. There is no more magic to it than that. You just add th two positions and divide by two. It's so easy a caveman could do it.
You do the same thing with Venus. You do the same thing with the Sun. You do the same withing Mercury. You do the same thing with Jupiter, etc. This is how Davison chart is made. It's nothing more than the average position of two charts.
Now what about this Mars-Venus conjunction thing? As we have recently learned, according to the principle of synastry, a Mars-Venus conjunction in Davison chart is considered the strongest possible sign of sexual attraction. It doesn't necessarily mean the two of you will ultimately marry or be happy together, but it does signify ultra-massive sexual attraction. More points are awarded for this aspect than any other possible aspect.
Given a fixed location of Venus and Mars, it should be possible to graph a solution set of all possible variable Mars-Venus combinations that will produce a conjunction between Mars and Venus in the Davison chart. Given the various positions in the solution set, it should be possible to calculate a real calandar date when each of these positions actually occured.
Given a graphed solution set, we should be able to compute a set of dates. Given a set of dates, we can apply a date rang to eliminate impossible or undesirable prospects. I doubt you would want to date some one 50 years older or younger than yourself. I doubt you could date someone born in 1809. All crazy dates would need to be filtered out by simply selecting those within an acceptable date range. It's just one SQL statement folks
Select * from VenusConjMars where Birthdate between '' and ''
There you would have it.
Now the real trick is to graph the solution set of all positions that produce a conjunction, and then use celestial mechanics to compute the date. This is where the math turns brutal. I am sure there is one guy in NASA reading this blog right now who is chuckling and laughing "Oh that's so easy a caveman could do it." Yeah, like anything else, it's easy when you know how. I didn't do so well in the complex mathematical modeling class.
Further, a conjunction between Mars and Venus in the Davison chart tells us nothing about the Sun signs. It also tells us relatively little about the Mars and Venus relate to each other between two Natal charts. I can easily imagine a bunch of scenarios where you might line up Cancers and Sagitarrians who have poorly aspected Mars and Venus signs, just because a Davison conjunction occured. The point is simple: A bunch of other comparisons will also be necessary to ferret out a really great candidate.
Want an example? If you read my last blog entry, carefully, you noted that the highest possible score for me is an Aries female born on 4/13/1979. She has a score 532. By no means is Aries considered a good match with Virgo. Now this particular Aries may well be, but wouldn't you prefer to look for a more ideal candidate? Maybe you would and maybe you wouldn't. The question goes to temperment.