NSF–DOE Rubin Observatory’s Secondary Mirror Installed

Rubin Observatory, funded by the U.S. National Science Foundation and the U.S. Department of Energy's Office of Science, is poised to kick off a new era in astronomy and astrophysics with the 10-year Legacy Survey of Space and Time (LSST), beginning in 2025.

The glass mirror, which was made by Corning Advanced Optics and polished by L3Harris, is the first permanent component of the telescope's state-of-the-art, wide-field optical system to be installed and will soon contribute to a better understanding of our Universe.

The L3Harris team used novel measurement techniques in the polishing process to manage such a large precision convex surface. The company also designed and built the secondary mirror cell assembly, which consists of a stiff steel mounting plate, 72 axial and six tangent actuators (that support and control the shape of the thin mirror under gravity), the mirror cell electronics and sensors, a thermal control system, and the mirror control system.

"Our 55-year legacy of designing and constructing high-end optical systems for space and ground continues with the world's largest active secondary mirror system built for the Rubin Observatory," said Charles Clarkson, Vice President and General Manager, Imaging Systems, Space and Airborne Systems, L3Harris. "With this milestone, we are closer to pushing scientific frontiers and charting the universe like never before, and we look forward to the science that will be discovered."