HiRISE Imager
HiRISE Imager The HiRISE Imager is the black cylinder in the center of the box-like test structure. At this point in the assembly, only the large primary mirror and smaller secondary mirror are present (not visible), and their axes are lined up vertically to minimize the effects of gravity sag on the telescope structure.

The HiRISE Imager is the black cylinder in the center of the box-like test structure. At this point in the assembly, only the large primary mirror and smaller secondary mirror are present (not visible), and their axes are lined up vertically to minimize the effects of gravity sag on the telescope structure. Test equipment below the cylinder injects light through the two mirrors; a large flat mirror above the entire test structure returns the light back to the test equipment verifying that the two mirrors are aligned.