GPS Accuracy With and Without Selective Availability

The images compare the accuracy of GPS with and without Selective Availability. Each image represents 24 hours of GPS data on the day before and after selective availability was discontinued on May 2, 2000.

Caption:
The image shows accuracy to within a radius of about 20 feet (6 meters).
Type: Illustration
Image Date: 2012
Credit: National Air and Space Museum, Smithsonian Institution
Origin: National Air and Space Museum, Smithsonian Institution, based off of data taken at the Erlanger National CORS station, National Geodetic Survey, NOAA.
Creator: Ashley Hornish
Innovations
Navigation Methods
 

540_chart_without_selective_availability.jpg

The image shows accuracy to within a radius of about 20 feet (6 meters).

540_chart_with_selective_availability.jpg

The image shows accuracy to within a radius of about 148 feet (45 meters).