Birth data and time zones
Enter the birth date, the local clock time at birth, and the birthplace in AstroCarto. The destination you want to investigate belongs in a city tool, not in the birth form. If any birth detail is wrong, correct it and generate a new map before continuing; editing the form or a saved record does not update an older result by itself.
What belongs in each birth field?
Open the map generator and use the details of the person whose map you want. A reliable starting point is the recorded birth information, with uncertainty kept visible.
| Field | Enter this | Avoid this mix-up |
|---|---|---|
| Birth Date | The person's calendar date of birth | Swapping day and month when copying between date formats. |
| Birth Time | The local clock reading at the birthplace when the person was born | Converting it to your current timezone or entering 12:00 merely because the time is unknown. |
| Birth Location | The actual birth city and country, confirmed against the full suggestion | Entering a current home or prospective destination instead of the birthplace. |
Check AM/PM if your device uses a twelve-hour clock. In a twenty-four-hour field, 00:15 is shortly after midnight and 12:15 is shortly after noon. Keep the date belonging to that local birth time; do not move it to another day to match the clock where you live now.
If you genuinely do not know the time, select I don't know my birth time. The estimated map uses a noon placeholder and retains the uncertainty. See unknown birth-time guidance for the resulting workflow limits. Paying for access does not supply a missing birth time.
Our correction example uses synthetic teaching details: 15 January 1990, London, United Kingdom. We initially entered 12:00, then changed the intended example time to 12:15. This is an input-correction exercise, not an attempt to discover someone's true birth time from a map.
How do I choose the right birthplace and timezone?
Type a city name, wait for the suggestions, and read the region and country before selecting one. In our London search, the suggestions included:
| Suggestion | What it distinguishes |
|---|---|
| Greater London, England, United Kingdom | The UK location selected for this example. |
| City of London, Greater London, England, United Kingdom | A more specific location within London; choose it only when it matches the intended birthplace. |
| London, Southwestern Ontario, Ontario, Canada | A different country and location despite the same city name. |
Selecting a matched suggestion supplies coordinates for timezone resolution. The calculation uses the resolved birthplace zone with the birth date and local time. Keep entering the recorded local time; do not separately subtract an hour for daylight saving or convert it to UTC first.
A manually typed place that has not been selected from the suggestions can expose a Timezone field after you leave the location input. In that route, check the timezone for the birthplace rather than your present location. A fixed UTC option is not a substitute for the historical local zone on every birth date. Prefer a matched birthplace suggestion when available; if you cannot establish the correct place or zone, keep the original birth record and ask for help instead of guessing an offset.
Use coordinates expects latitude followed by longitude. In this example the selected UK suggestion supplied approximately 51.5074456, -0.1277653. The negative longitude matters. Coordinates must describe the birthplace, not the destination or a point you clicked on the map. Entering valid coordinates does not establish whether an uncertain birth time is accurate.
Some local clock times repeat or do not exist during daylight-saving changes. A failed calculation is not enough to identify the cause: the birth form may show a general failure rather than a detailed timezone explanation. Recheck the original date, time, and full birthplace; do not shift the time until the form accepts it. If the problem remains, include those details and the visible error when contacting support. The calculation-method page explains the broader basis of the map.
How do I correct a birth time or birthplace?
Correct the source input first, then create a result from that corrected input. Do not continue interpreting the old map just because its form now looks right.
- Return to the birth-details form. Check the date, time, unknown-time option, and full birthplace together.
- Replace the incorrect value. For a place correction, choose the matching suggestion again so the place and coordinates belong together.
- Select Generate Your Chart and wait for the calculation to finish.
- Check the date and birthplace beside Your Astrocartography Map. Open the birthplace marker's information to check the displayed time as well.
- Re-run the city research or other result you intend to use. An older report or downloaded PDF still belongs to its original input.
Here is what happened in our actual correction exercise:
| Stage | Birth form | Map still on screen | Judgment |
|---|---|---|---|
| Initial result | 1990-01-15, 12:00; London entered as the birth city | London and 12:00 | This is the initial calculation, not the corrected one. |
| Input edited | 12:15 and the full Greater London, England, United Kingdom suggestion | The previous result still showed London and 12:00 | Editing alone has not updated the displayed calculation. |
| Generate pressed again | 1990-01-15, 12:15; selected UK birthplace | The full UK label and marker time 12:15 | The result now corresponds to the corrected example input. |
The table verifies which input belongs to which result. It does not establish how far every line moved or whether a city became better. Those claims would require reading the corresponding recalculated output. If the time remains uncertain, return to the limits of an estimated map rather than treating a plausible-looking result as confirmation.
A useful note is: “Corrected time to 12:15; regenerated the UK-birthplace map; old reports still use the earlier input.” This makes it harder to mix old and new evidence when you resume the research.
How do I keep using the corrected details?
If you use Stored Astro Data, update the appropriate person's record explicitly. When reusing it, check the loaded fields before calculating; a stored label alone is not proof that the expected time or place was loaded. Follow save and reuse birth details for that workflow.
Updating a birth record and regenerating a result are separate actions. Use saved data and results to distinguish the record, a saved place, a completed report, and a downloaded file. Keep older outputs identifiable instead of treating them as automatically corrected.