About the ephemeris
What the positions mean, and what they can and cannot tell you.
This site shows the daily positions of the seven points of the Diamond Astrology Ephemeris published by astrolab.nl. Every figure on this page was measured from the full source data, 1901–2050.
Reading a day
Each day gives one position for each of seven points. A position is an ecliptic longitude, an angle from 0° to 360° around the zodiac. It is shown the astrological way, as a sign plus degrees and arcminutes, which is the same angle cut into twelve 30° slices: 7°59′ Taurus means 7 degrees 59 minutes into the second slice, or 37.98°.
Here is 1 January 2021:
| Point | Position | Longitude |
|---|---|---|
| Black Moon Lilith (mean) | 7°59′ Taurus | 37.98° |
| Black Moon Lilith (true) | 18°04′ Taurus ℞ | 48.07° |
| Priapus | 7°59′ Scorpio | 217.98° |
| Black Sun | 13°16′ Cancer | 103.27° |
| Diamond | 13°16′ Capricorn | 283.27° |
| Unidentified point 6 | 2°59′ Pisces | 332.98° |
| Unidentified point 7 | 22°14′ Gemini | 82.23° |
There is no location and no house information, and none is needed: ecliptic longitude doesn't depend on where you are. The same positions apply everywhere on Earth.
Coverage is unbroken: every calendar day from 1 January 1901 to 31 December 2050, 54,787 days in all, with no gaps.
The points move at very different speeds
| Point | Motion per day | Direction | Distinct values in 150 years |
|---|---|---|---|
| Lilith (true) | −78′ to +92′ | reverses; retrograde 42% of days | 19,952 |
| Lilith (mean) | 6′–7′ | always forward | 21,075 |
| Priapus | 6′–7′ | always forward | 21,075 |
| Point 6 | 0′–1′ | always forward | 9,001 |
| Point 7 | 0′–1′ | always forward | 4,951 |
| Black Sun | 0′–1′ | always forward | 142 |
| Diamond | 0′–1′ | always forward | 142 |
- Black Sun and Diamond are effectively constant. They take only 142 distinct values in 150 years, roughly one change every 13 months. Black Sun stays between 11°14′ and 13°47′ Cancer across the whole range (Diamond mirrors it in Capricorn), moving about a degree in a lifetime.
- The two Liliths and Priapus genuinely depend on the date. Lilith (mean) moves a full degree every nine days.
- Lilith (true) is the volatile one. It can swing 1.5° in a single day and it reverses direction.
Long-term drift, measured over 2021–2025:
| Point | Degrees per year |
|---|---|
| Lilith (mean) | +40.658 |
| Lilith (true) | +41.008 |
| Priapus | +40.658 |
| Point 6 | +1.001 |
| Point 7 | +0.550 |
| Black Sun (the precession of the solar apogee) | +0.017 |
Motion markers
Each position in the source carries a motion marker, shown on the lookup page as ℞ for retrograde and St for a station. A position without a mark is direct.
Almost all of the variation is in Lilith (true): across 150 years it is direct on 31,588 days, retrograde on 23,098, and stationary on 101 days, which almost always fall on days with no motion at all. The only other marker in the whole dataset is a single station on Unidentified point 7, on 27 May 1913.
Two pairs of exact opposites
On every day in the data, to within floating-point precision:
- Priapus = Lilith (mean) + 180°. Priapus is the mean lunar perigee; Lilith is the mean apogee.
- Diamond = Black Sun + 180°. Diamond is the solar perigee; Black Sun is the apogee.
Priapus is opposite Lilith mean, not Lilith true. Against the true Lilith it is off by up to 12.3°, and not one day comes within 0.02° of opposition.
What the data does not tell you
The time of day is not recorded. The source gives one position per day but never says which moment it represents. Ephemerides are conventionally tabulated for 00:00 or 12:00 UT, but these tables don't say.
For the slow points this makes no difference. For Lilith (true) it matters: a half-day difference can shift it by up to about 46 arcminutes, far more than the printed precision of one arcminute. Treat a single day's Lilith (true) position as approximate.
Points 6 and 7 are unidentified. The source doesn't name them. They move smoothly and always forward, at about 1.0° and 0.55° a year, so they are computed quantities of some kind, but which ones is unknown.