![GPS satellite](/sites/default/files/styles/crop_freeform/public/2023-11/gps-timeline-lockheed_martin-promo.jpg?itok=3aIs-z3v)
Credit: Lockheed Martin
Now in its seventh iteration of spacecraft design, GPS remains the most used and relied upon among the several systems now providing space-based position, navigation and timing. Click in the upper right corner of the timeline below to view it in full-screen mode.