Correct for Daylight Savings Time (DST)
Determining the appropriate timezone, DST value and UTC offset are all challenging aspects of calculating astrology charts. Yet these are extremely important values to determine correctly in order to calculate an accurate chart.
While this isn't the place to go into the topic in depth, one simple way of explaining the problem facing every astrologer is this:
How do we know whether Daylight Savings Time was in effect or not at the birth (or event) moment?
The only way to ever know for sure is to research local records such as newspapers or governmental policy documents to see if Daylight Savings Time was in effect or not in that location and at that time.
Many astrology programs use the ACS Atlas to determine such issues which is an older atlas that doesn't always receive the most recent updates, especially for newer time periods (post 1970).
LUNA uses the modern standard system that's utilized in all internet software which is called the IANA TimeZone Database.
Why is the chart different in LUNA than in other astrology programs?
While the IANA database is accurate and updated regularly, it is less concerned with dates prior to 1970.
As such, you should review the offset that the IANA database automatically calculates, and determine if an adjustment needs to be made.
How to I adjust my chart for DST?
LUNA makes it easy to adjust your chart regardless of what the automatic timezone and DST detection is:
- When viewing the chart in question, select the "Edit" link to open the chart edit screen.
- At the bottom of that screen is information related to the UTC offset, timezone and DST value.
- Select the pencil icon that's listed next to the UTC offset and you will see a popup window that lets you change this value.
- Enter the UTC offset you want to use instead of the automatic one and your chart will calculate according to the new value.
When you select the pencil icon next to the UTC offset, this popup will appear which will let you manually adjust the UTC offset.