Assumptions for these calculations:

- Latitude between 41° to 42° N, appropriate for Cook County, IL.
- 1/1000° latitude is about 111 meters, or 1 meter is about .000009°.
- 1/1000° longitude is about 83.5 meters, or 1 meter is about .000012°.
- For the north point, 50 m is about .00045° latitude, simply add the latitude from the center.
- For the 120° point: 50 m is the hypotenuse of a right triangle with 30° and 60° angles.
- The short side (south) is 25 m, or subtract .000225° latitude.
- The long side (east) is 43.3 m, or subtract .000520° longitude.

- For the 240° point: subtract .000225° latitude, add .000520° longitude.

Designed by Peter Chen for Habitat Project.

Mirrors: http://www.nicerweb.com/doc/class/pix/LandAudit/GPS_calculator.html http://www.cod.edu/people/faculty/chenpe/LandAudit/GPS_calculator.html