Professional-Precision Progressed Chart Calculation
Numji's secondary progression calculation infrastructure was compared against astronomical references and independent geometric controls across 250 test cases generated from various dates, times, geographical locations, and target years. A total of 33,757 results were examined for the natal baseline, progressed planets, and Progressed–Natal aspects.
Natal and progressed planet positions, motion directions, natal houses, natal house placements of progressed planets, Progressed–Natal aspects, and orb values passed the established acceptance criteria. Three results were separately reviewed as they were extremely close to the natural orb threshold; no failed results were found.
Validated Progressed Chart calculations
The primary result groups forming the temporal, astronomical, and geometric foundation of the secondary progression technique.
SECONDARY PROGRESSION TIME
The time conversion where one tropical year corresponds to one ephemeris day was independently checked at the level of target age and progressed UTC moment.
NATAL AND PROGRESSED PLANETS
Natal and progressed planetary longitudes alongside direct/retrograde motion directions were compared with reference values.
NATAL HOUSES AND PLACEMENTS
Natal ASC–MC, the twelve natal house cusps, and the placements of progressed planets in natal houses were checked.
PROGRESSED–NATAL ASPECTS
Aspect types, true angles, orb values, and applying–separating statuses were validated through independent geometric calculation.
Validation results
Numerical distribution of the tested calculation groups. Boundary cases were evaluated separately and are not classified as failures.
| Calculation Group | Comparison | Compatible | Boundary Review | Result |
|---|---|---|---|---|
| Time conversion | 750 | 750 | 0 | Passed |
| Natal axes: ASC and MC | 500 | 500 | 0 | Passed |
| Natal house cusps | 3,000 | 3,000 | 0 | Passed |
| Natal planet positions and motion directions | 6,500 | 6,500 | 0 | Passed |
| Progressed planet positions and motion directions | 6,500 | 6,500 | 0 | Passed |
| Natal house placements of progressed planets | 3,250 | 3,250 | 0 | Passed |
| Progressed–Natal aspect type, true angle, and orb | 9,753 | 9,753 | 0 | Passed |
| Applying–separating status | 3,251 | 3,251 | 0 | Passed |
| Orb boundary membership checks | 3 | 0 | 3 | Reviewed |
| Independent repeat check | 250 | 250 | 0 | Passed |
| Total | 33,757 | 33,754 | 3 | Passed |
Highlighted precision results
Summary of average and maximum differences observed in the test set.
| Measurement | Average Difference | Maximum Difference | Evaluation | Result |
|---|---|---|---|---|
| Progressed planet positions | 0.000599° | 0.013688° | Within acceptance criteria | Passed |
| Natal planet positions | 0.000590° | 0.014775° | Within acceptance criteria | Passed |
| Natal axes and house cusps | 0.002318° | 0.015568° | Within acceptance criteria | Passed |
| Progressed–Natal aspect orbs | 0.000846° | 0.014872° | Within acceptance criteria | Passed |
| Chiron positions | 0.00000345° | 0.00110303° | 500/500 compatible | Passed |
| Moon positions | — | 0.013688° | 500/500 compatible | Passed |
| Lunar nodes | — | 0.000321° | 1,000/1,000 compatible | Passed |
Why do boundary cases occur?
When an astronomical value is extremely close to a classification line, very small numerical differences can produce different membership tags.
ORB THRESHOLD
Three aspects were located right next to the orb boundary used. A very minor geometric difference affected whether the aspect was classified as inside or outside the boundary.
NUMERICAL FOUNDATION COMPATIBLE
In these three cases, planetary longitudes and true angle values were within acceptance criteria. The separate review pertains solely to the boundary aspect membership label.
Test methodology
The goal was to ensure the results rely on wide time, location, and calculation diversity rather than a single chart.
SCOPE
- 250 distinct test cases
- Target dates between 1900–2100
- A wide range of birth dates, times, and locations
- Total of 33,757 comparisons
INDEPENDENT CONTROLS
- Comparison with astronomical reference data
- Independent generation of secondary progression time
- Recalculation of aspect and orb geometry
- Applying–separating and repeat consistency check
SPECIAL POINTS
- Moon, Chiron, North Lunar Node, and South Lunar Node were additionally tracked. All position and motion direction results for these points remained within acceptance criteria.
INDEPENDENT CALCULATION
Reference sources were used strictly for comparison purposes. Numji's production calculations are executed within its own calculation infrastructure independently of the validation tool.
What does this result mean for the astrologer?
The time conversion, planetary degrees, natal house placements, and aspects formed with the natal chart upon which Progressed Chart interpretation relies are delivered with a calculation infrastructure backed by an extensive numerical validation set. This allows astrologers to focus on holistically evaluating the symbolic developmental themes of the progressed chart rather than technical computations.