Part of Fortune: the point nobody talks about
The oldest of the Arabic parts, and the one most calculators compute incorrectly.
2 min read · Published 29 August 2026
First, the answer
The Part of Fortune is a calculated point marking where the Moon would be if the Sun were rising. By day the formula is Ascendant plus Moon minus Sun; by night it reverses to Ascendant plus Sun minus Moon. Many free calculators apply the day formula regardless, which puts the point up to half the zodiac away from where it belongs. It requires an exact birth time.
The sect problem
The formula depends on your sect, whether the Sun was above or below the horizon. Day charts use ASC + Moon − Sun; night charts use ASC + Sun − Moon. Reversing the terms reflects the point across the Ascendant axis, up to 180 degrees away.
AsterNym determines sect from the Sun's actual altitude at your birth and shows it on the page.
What it means
Traditionally, where things come together for you: prosperity and ease, not mystical luck. The house shows the area of life; the sign shows the manner. It is the oldest of the Arabic parts, dozens of which exist in the medieval literature. Almost none are used today.
I compute it, I check the sect, and then I ignore it. The Part of Fortune is a lot of arithmetic for a point nobody can define.
Reading it by house
| House | Traditionally read as |
|---|---|
| 1st | Your own presence. Things go well when you are visibly yourself |
| 2nd | What you own and earn; security built by hand |
| 3rd | Conversation, siblings, the local world |
| 4th | Home, family, roots |
| 5th | Play, romance, creative work made for its own sake |
| 6th | Daily work, craft, health, reward through repetition |
| 7th | Partnership. The other person is the route rather than a detour |
| 8th | Shared or inherited resources; depth |
| 9th | Distance, study, belief: prospering away from where you started |
| 10th | Public work and reputation |
| 11th | Friends and networks; luck arriving through people |
| 12th | Solitude, and what you do without an audience |
Before you lean on the Part
Nothing is physically there. It moves as fast as the Ascendant, roughly a degree every four minutes, and there is no evidence that it indicates anything. Yours is on your natal chart when a birth time is recorded.
How is the Part of Fortune calculated?
By day, Ascendant plus Moon minus Sun. By night, Ascendant plus Sun minus Moon.
Why do calculators disagree about my Part of Fortune?
Many apply the day formula regardless of sect, which is wrong for every night birth.
Do I need a birth time for the Part of Fortune?
Yes. It is calculated from the Ascendant, which moves about a degree every four minutes.
Xavier Brooks