Question: What functions can a GPS receiver alone perform? What additional technologies make a GPS receiver useful? What other functions must be added to enable remote tracking via GPS? Why was GPS data deliberately corrupted for many years? What are some challenges in performing S&R from spacecraft? Why was the CORONA program significant at the time? How were CORONA images retrieved from the spacecraft? Why was the CORONA image shown in the lecture significant? Why are CORONA images still useful today? Need Assignment Help?