This week in 1978, the High Energy Astronomy Observatory 2 was launched from NASA’s Kennedy Space Center aboard an Atlas-Centaur rocket. HEAO-2, the second of three HEAO satellites, was renamed Einstein after launch and was the first fully imaging X-ray telescope put into space. It was also the first NASA mission to have a guest observer program. Here, the HEAO-2 telescope is checked by engineers in NASA Marshall Space Flight Center’s X-ray Calibration Facility. Today, NASA’s satellite X-ray telescope, the Chandra X-ray Observatory, is managed by the Marshall Center. The NASA History Program is responsible for generating, disseminating, and preserving NASA’s remarkable history and providing a comprehensive understanding of the institutional, cultural, social, political, economic, technological, and scientific aspects of NASA’s activities in aeronautics and space. For more pictures like this one and to connect to NASA’s history, visit the Marshall History Program’s webpage.