Sun Alignment Date Finder
Find dates and time windows when the Sun matches your chosen true azimuth and elevation within an explicit angular tolerance.
Starts with an editable example. Replace the dates and rules with your own.
Your calculation
Ready when you are
Choose your dates.
Select your counting rules and calculate.
Calculation details
| Step | Value |
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How to use this calculator
Enter location, time zone, date range, azimuth clockwise from true north, Sun-center elevation and tolerance on both angles.
Uses geometric Sun-center altitude without refraction. Terrain, structures and magnetic declination are not modeled. Search up to 366 local dates; near-zenith positions above 89.9 degrees are excluded.
A worked example
In New York, searching late May for a west-northwest direction near 299 degrees and a low Sun gives short evening alignment windows.
Can I enter a compass bearing directly?
Use a true-north bearing. A magnetic compass reading needs its local declination correction before it can be compared with astronomical azimuth.
Further reading: Astronomy Engine methods. Your entered rules determine this result.
Which calendar and years are supported?
Gregorian input coverage is 1900-2100 unless the method states a narrower range. Results explain calendar conventions and local date boundaries. Astronomy uses a level horizon at sea level. CSV, print and copy retain the result rules; calendar files contain only calculated events. Nothing is scheduled automatically.
What happens to my dates?
Calculations run on your device. Saving a calculation is optional and keeps it in this browser. A setup link contains the dates and settings you entered; anyone with the link can read them. Use one tab per saved calculator. Clear saved data from Privacy & settings.