The math for this isn't really hard, it's just tedious. This works only for Ascendant/Descendant. For Primary Directions to the MC, it's different math (but easier) since you're working mostly with Right Ascension. Planet to Planet aspects is not too much more complicated, but different still.
There are only 5 terms you need to know (and the abbreviations I use so I don't have to type/write so much):
1] Ascensional Difference (AD): difference between the Right Ascension (RA) and Oblique Ascension (OA).
2] Semi-Arc (SA): the Ascensional Difference (AD) +/- 90° it is added if Declination is North, but subtracted if Declination is South (and I hope people living in the Southern Hemisphere understand that is reversed and why).
3] Meridian Distance (MD): is the difference between the Right Ascension of the Midheaven (RAMC) and the Right Ascension of the Nadir (RAIC) and the Planet's Right Ascension.
4] Arc of Direction: the difference between the Semi-Arc (SA and the Meridian Distance (MD).
5] Equatorial Time: Proportion of Distance traveled. Simply divide by 12
Going back to this Chart, we'll use Ptolemy's method to calculate the base Life-Span:
The Lot of Fortune is Hyleg, and we want to move it to the Descendant.
First, find the Ascensional Difference (AD):
AD(Fortuna) = RA(Fortuna) - OA (Fortuna)
The Birth Latitude is 42°N57' and I should really interpolate that, but I'm too lazy right now, so I'm just going to use tables for 43*°N. My tables are to the nearest 10' of arc and I should interpolate that as well, but I just want to show the gist of the math.
The Lot of Fortune is at 12*°Can35' which is 102°35' in Celestial Longitude and at this point I'll simply say that all Longitudes are converted to Celestial Longitude. For example, the Descendant is 9° Gem38' and Gemini is the 3rd Sign (Aries is 1st, Taurus 2nd etc) so:
Gemini 3rd Sign - 1 = 2 * 30° = 60° + 9°38' = 69°38'
Virgo 6th Sign - 1 = 5 * 30° = 150° = 28°36' = 178°38'
So there is the Midheaven converted to Celestial Longitude and that is how you convert to Celestial Longitude for an Planet or Chart Point.
From the tables then:
AD(Fortuna) = 103°35' - 80°27' = 23.13°
The Lot of Fortune always has the same Ecliptic Latitude as the Moon, which +0(N) in this chart, so we add 90**°:
Semi-Arc (SAFortuna) = AD + 90*° = 23.13° + 90° = 113.13°
Meridian Distance (Fortuna) = RAMC - RAFortuna
MD = 178°44' - 103°35' = 75.15°
Arc of Direction = SA (Fortuna) - MD (Fortuna) = 113.13° - 75.15° = 37.98°
So, the base Life-Span is 37.98° or 37 years and 12 months or so.
Now we will add or subtract the Rays of the Malefics and Benefics to get the actual Life-Span. This is exactly as I told you in the previous posts, but now we're going to do the math.
We want the Benefic Venus to cast her life saving Rays and Light on the Descendant from her trine. Venus will trine the Descendant at 9° Aquarius and that's where we want to move her.
So we start the process all over again. Don't be intimated. It's just like home-work, you do it repeatedly until you gain confidence in your calculations (but always go slowly and check for mistakes).
AD(Venus) = RA(Venus) - OA(Venus) = 347°44' - 352°40' = -4.93°
The Ecliptic Latitude of Venus is -1°(S) and when you subtract a negative number the negative signs cancel out and you actually add, so:
SA(Venus) = 90° - (-4.93°) = 94.93°
MD(Venus) = RAIC - RA(Venus) = 358°56' - 352°40' = 6.18°
Arc of Direction (Venus) = SA(Venus) - MD(Venus) = 94.93° - 6.18°
Now, before we actually do this, we need to understand the Celestial Mechanics. We are not moving Venus to the Ascendant, rather we are moving Venus to a point along the arc.
We need to find the proportion of the arc that Venus will travel. The total number of degrees between the Ascendant and the Nadir (Imum Coeli) is 97° and we are moving Venus 37° to 9° Aquarius.
37° / 97° = 0.38 so first we must multiply SA(Venus) by 0.38
0.38 * 94.93° = 36.07° and now we can complete the equation:
Arc of Direction = 36.07° - 6.18° = 29.89°
And now we convert to Equatorial Time:
29.89° / 12 = 2.49°
And this we add to the base Life-Span:
37.98° + 2.49° = 40.47° or about 40 years and 3 months
Now we bring Saturn to the opposition of the Descendant.
AD(Saturn) = RA(Saturn) - OA (Saturn) = 332°05' - 343°00' = -11.91°
Saturn's Ecliptic Latitude is -1°(S) so again subtracting a negative we add:
SA(Saturn) = 90° - (-11.91°) = 101.91°
MD(Saturn) = RAIC - RA(Saturn) = 358°56' - 332°05' = 26.85°
Arc of Direction = SA(Saturn) - MD(Saturn) = 101.91° - 26.85° = 75.07°
Equatorial Time = 75.07° / 12 = 6.26°
Saturn has just taken a little over 6 years off of his life span:
40.47° - 6.26° = 34.21° or about 34 years and 2 months.
Now we bring Mars to the square of the Descendant.
AD(Mars) = RA(Mars) - OA(Mars) = 201°54' - 210°36' = -8.7°
The Ecliptic Latitude of Mars is +2°(N) so we add 90°
SA(Mars) = 90° + (-8.7°) = 81.3°
Mars is in Quadrant I:
MD(Mars) = RA(Mars) - RAMC = 201°54' - 178°44' = 23.17°
Once again, Mars is not moving the entire arc, just a portion of it. Mars has already traveled 37° or a little over 1/3 of the way to the Midheaven, so he has to travel 63° or about 2/3 of the way to get there.
90° - 37° = 53° / 90° = 0.59
Arc of Direction = (81.3 * .59) - 23.17° = 24.79°
Equatorial Time: 24.79° / 12 = 2.06°
34.21° - 2.06° = 32.15 or about 32 years and 1 month.
Now Jupiter.
AD(Jupiter) = RA(Jupiter) - OA(Jupiter) = 230°06' - 248°10' = -18.07°
Jupiter's Ecliptic Latitude is +1°(N) so:
SA(Jupiter) = 90° + (-18.07°) = 71.93°
MD(Jupiter) = RA(Jupiter) - RAMC = 230°06' - 178°44' = 51.37°
Again, Jupiter isn't going the distance, he's just moving to 9° Libra to cast a life saving trine to the Descendant.
That is 30° Jupiter doesn't have to travel, and he's already traveled 17° for a total of 47° the whole distance is 90° so
90° - 47° = 43° / 90° = 0.47
Arc of Direction = (71.93 * 0.47) - 51.37° = 33.8° - 51.37° = -17.57
Equatorial Time: -17.57 / 12 = -1.46
Ooopps!
Yeah, that.
But we already knew that. Look where Jupiter is. Jupiter is in the 12th House. I call it the Anti-House.
Here's what Ptolemy says, lest anyone be confused:
Ptolemy Book III Chapter 12 said:
...hence the sign which precedes the ascendant, and constitutes the twelfth house (called that of the Evil Demon), is incompetent; and not only for the above reason, but also because it is cadent, and because the beams cast by the stars posited therein, towards the earth, are impaired by the thick and dark exhalations arising from the earth's vapours, which produce an unnatural colour and magnitude in the appearance of stars so posited, confusing, and in some measure annihilating, their beams.
Jupiter is trapped in the 12th House, Cadent, inconjunct the Ascendant and Descendant, Slow in Motion, totally Out of Sect being a Day Planet that is Nocturnal, in a Feminine Sign and House, Peregrine in the Sign of Scorpio and in the Term of an afflicted Mercury.
In spite of Jupiter's most heroic efforts, Jupiter cannot cast his life saving rays on the Descendant to save the Native.
Jupiter is the Great Preserver, he will not kill, but he cannot save in this instance.
32.15 is where we are.
Lieutenant Commander Roger Chaffee died on board an Apollo space module on the launch pad on January 27, 1967, just 19 days before his 32nd Birthday.
That's the process for a Hyleg that is in Quadrant II, the Occidental Quadrant, a Feminine Quadrant. When the Hyleg is in Quadrant I (Oriental and Masculine) you direct the Hyleg counter-clockwise. That's a little more difficult because it requires more judgments, and you have to pay careful attention to everything that is happening in the chart.
For example, suppose the Moon were Hyleg in the 10th House, we would direct it counter-clockwise and naturally we would be interested in the time when Moon comes to Mars. Mars is in the Term of Mars, and no Planet casts its benefic rays there, so we might conclude that would be death as well. However, Sun trines Mars, so we would have to weigh the condition of the Sun to see if it would mean death, and being that Sun is conjunct Mercury, that would probably be the case. But if Mars were in the Term of Venus or Jupiter, or if Venus or Jupiter aspect Mars or the Term, then we might conclude an unfortunate incident, maybe even a life threatening accident or illness, but not death. And you also look at Primary Directions to see if Jupiter or Venus were in aspect with that point, because they can save then, too. As you can see, it's a little more difficult here than when the Hyleg is in Quadrant II.
Also note that had I been more precise in the calculations, I would have gotten a much closer date of death.