 Complete the following phrase:  Blackstar is the reported codename of a secret United States orbital spaceplane system. The possible existence of the Blackstar program was reported in March 2006 by Aviation Week  Space Technology Aviation Week, AWST magazine; the magazine reported that the program had been underway since at least the early 1990s, and that the impetus for Blackstar was to allow the United States government to retain orbital reconnaissance capabilities jeopardized following the 