What does a transit chart compare?
A transit chart compares the planets at a chosen moment with the positions in a natal chart. The natal layer stays fixed while the transit layer changes with the date and time. It is useful for studying which moving planets form aspects to natal positions, rather than recalculating the birth chart for today.
How to use this tool
- Create a birth profile or select a chart from History, Saved Charts or My theme. Check the original birth data before comparing it.
- Set the transit date and local time. Today returns to the current moment, and the day arrows let you compare nearby dates.
- Open the location control to choose the transit city. Check its time zone, then use the wheel, Table or Aspects to inspect the comparison.
How to read the two layers
Keep track of which planet belongs to which date. A transit Saturn to natal Moon aspect connects a moving Saturn position with the Moon’s birth position. Reversing the two layers changes the question. The comparison labels in the tables help you keep them separate.
Follow one planet across several dates to see how an aspect’s orb changes. Slow and fast planets move at different rates, so a daily change that is clear for the Moon may be subtle for an outer planet. The monthly ephemeris offers a broader view of this movement.
Before interpreting the result
A transit chart is a comparison of positions, not a list of guaranteed events. An uncertain birth time also makes natal houses and angles uncertain. Use the displayed date, time zone and coordinates to check the calculation before interpreting it.
Common questions
Can I choose a past or future transit date?
Yes. Change the date and time controls above the chart. The selected time is local to the transit city’s time zone, not automatically UTC.
Does changing the transit location change my birth data?
No. The transit location is a separate calculation setting. Your original birth profile remains the basis of the natal layer.
Why is the transit aspect list different from the natal list?
The transit list compares planets from two different dates. It also uses the transit tool’s aspect and orb settings, so it is not a copy of the aspects within your birth chart.