Satellite-servicing technology is being used to upgrade the Hubble Space Telescope to perform beyond its initial design requirements. Twice astronauts have replaced the telescope's solar panels with higher-performance ones. The most impressive improvement, however, has come with the installation of a new camera to record the images seen by the Hubble . Its increased sensitivity makes it ten _______ as powerful as its predecessor, and it has produced dramatically sharper images, some of them of stars and galaxies that were invisible to the old Hubble.