Transit Timing
Transit Timing
- Pay attention to Retrograde periods.
- Use exact aspect dates to predict peak influence.
Backlink: Transit Overview.
⏱️ Timing Arithmetic
- Exactness: a transit is exact when
|d − A| = 0; peak influence is usually within ±1° for slow planets. - Triple passes: an outer planet that stations near a natal point makes up to three exact hits (direct, retrograde, direct) over ≈ 6–12 months — see Retrograde Motion.
- Stations: a station within 1° of a natal point is the strongest form of a transit.
- Eclipses: occur when a new/full Moon is near the lunar nodes; there are 4–7 eclipses per year in two eclipse seasons ≈ 173.3 days apart (the eclipse year is 346.62 days).
- Mean daily motion (for date estimation): Sun 0°59′; Moon ≈ 13°11′; Mars ≈ 0°31′; Jupiter ≈ 0°05′; Saturn ≈ 0°02′; Uranus ≈ 0°00′42″; Neptune ≈ 0°00′22″; Pluto ≈ 0°00′15″ (long-run means).
Return and half-return table
| Cycle | Period | Milestones |
|---|---|---|
| Jupiter return | 11.86 y | ≈ 12, 24, 36, 48, 59, 71 |
| Saturn return | 29.46 y | ≈ 29.5, 59, 88 (squares ≈ 7, 14, 22) |
| Nodal return | 18.6 y | ≈ 18.6, 37.2, 55.8, 74.4 (half ≈ 9.3) |
| Chiron return | ≈ 50.6 y | ≈ 50–51 |
| Uranus opposition / return | 84.0 y | ≈ 40–42 / 84 |
| Neptune square | 164.8 y | ≈ 39–43 |
Sources (method)
- NASA NSSDCA Planetary Fact Sheet (D. R. Williams): https://nssdc.gsfc.nasa.gov/planetary/factsheet/
- NASA/JPL Small-Body Database (SBDB) API, osculating heliocentric elements and discovery circumstances, queried 2026-11-06: https://ssd-api.jpl.nasa.gov/sbdb.api
- Jean Meeus, Astronomical Algorithms, 2nd ed. (Willmann-Bell, 1998) — ch. 13 (coordinate transforms), ch. 47 (Moon, nodes, perigee/apogee)