 During the great geomagnetic storm of March 1989, four of the Navy's navigational satellites had to be taken out of service for up to a week, the U.S. Space Command had to post new orbital elements for over 1000 objects affected and the Solar Maximum Mission satellite fell out of orbit in December the same year.The vulnerability of the satellites depends on their position as well.The South Atlantic Anomaly is a perilous place for a satellite to pass through.