So I’ve come across more than one puzzle cache that goes something like this: you are given a coordinate. The description then tells you to go X feet from the coordinate heading y degrees. How do you calculate the new coordinates?
Well, you perform some trigonometry to identify the longitudinal and latitudinal distances then perform some algebra to convert those distances into coordinates. Something new that I learned is that the distance between each longitudinal degree is different than the distance between each latitudinal degree. Hence you have to use different divisors for each to determine the coordinates.
The calculator still needs to handle situations where the distance hops over a longitudinal or latitudinal degree, but for most puzzles of this type the calculator will work fine. The calculator even handles jumps over degrees, so adding thousands of feet shouldn’t trip it from providing the correct coordinates.
Here’s what to enter:
- Distance (Feet) = the distance from the center point in feet. If you’re interested in metric entry and results, post a comment.
- Heading (Compass Degrees) = the heading in compass degrees. 0 degrees is due North, 90 degrees is due East, 180 degrees is due South, and 270 degrees is due West.
- Latitude of Origin “N” = coordinates in the format “N XX° YYY.ZZZZ'” where XX is the degrees and YYY.ZZZZ is the decimal minutes. This is the common form that Geocaching.com provides for coordinates.
- Longitude of Origin “W” = the same as the Latitude, only for Longitude. Because it’s frozen as “W”, this calculator will only work for the western hemisphere. Let me know if you’re in the Eastern (or Southern) hemisphere and would like me to update the calculator to accommodate you.
The Calculations are for nerds. The Results are for you. The coordinate results should display a link to Google maps when you’ve entered in all the criteria.
Update: 2017-06-15, I corrected the algorithm. Instead of using the angular distance, it uses a formula based on Haversine distance equation.
Have fun and post a comment to let me know if it’s useful.