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MIKE'S BUILD YOUR OWN SUNDIAL

You can build a perfectly functional analemmatic sundial ranging in size from a handheld to one covering a garden. Enter the information in the form below and you will be given 3 designs based on your needs.

DATE:
Your time zone (EST=5, CST=6, PST=7, etc):
Overall length of clock (units don't matter):
Latitude: '
Longitude: '

Decide how long you want the long axis of the ellipse to be and enter that number as length. For example, if you want the clock to be 10 feet wide, enter 10. The units don't matter (meters, miles, furlongs, whatever.)


The following are descriptions for the 3 designs that will be available for your sundial:


CLASSIC DESIGN - this gives local time, uncorrected for where you are in your particular time zone. It is NOT the same thing as the time on your watch. The sundial will read 12:00 when the sun reaches its highest point at your location. In this design, the 12 is at the top and 0600 and 1800 (6PM) are on the left and right sides, respectively


CORRECTED DESIGN - at the moment your clock shows 12:00, someone with the same clock who is 200 miles to your east will show a time of 12:12 since the sun reached its highest point there around 12 minutes earlier. (The sun makes it's trip around the earth at about 1000mph.). So, a little correction is built in to take into account your longitude. Read about equation of time to see why, even with the correction, your clock will still usually not read 12:00 when your watch says 12:00.


DAYLIGHT SAVINGS TIME - this corrects for Daylight Savings time. Note that 1:00 will be approximately at the top instead of 12:00.