Longitude, aspects and orbs
An aspect is a named target angle on a continuous separation, not a market event. · 8 min
Continuous angle first
The first-class quantity is the minimum angular separation of two longitudes, in [0°, 180°]. Named aspects (conjunction 0°, square 90°, opposition 180°, …) are labels on that number plus an orb (a tolerance).
Jupiter–Saturn at 2020-12-21 18:20 UTC. Geometry only.
Separation
0.00°
Nearest
☌ Conjunction
|orb|
0.00°
Phase
exact
Key points
- Orb is configurable per experiment. Defaults in the geometry engine are display conventions, not physical constants.
- Applying / separating is
d(separation)/dtfrom longitude velocities, not a tradition-specific rule. - The 2020-12-21 Jupiter–Saturn conjunction is a geometry fixture in the test suite (~18:20 UTC).
Method
When you later run an event study, “Mars square Jupiter with a 3° orb” is a boolean mask over this continuous geometry. The Lab still has to compare that mask to a market sample with controls.
References
- astronomy-engine pairwise geometry
- Explanatory Supplement to the Astronomical Almanac — Urban S.E. and Seidelmann P.K. (eds.), 3rd ed., 2013