The University of Arizona

Steward Observatory Mirror Lab Ready To Cast LSST M1/M3 Monolith

LSST.org March 2008 | Casting of LSST’s unique M1/M3 mirror is underway! In January 2005 LSST Corporation awarded the contract to the University of Arizona Steward Observatory Mirror Lab (SOML) to purchase Ohara E6 low expansion glass and begin engineering work for the M1M3 monolith for the Large Synoptic Survey Telescope (LSST). The primary (M1) and tertiary (M3) mirrors are designed as one block of glass: vertically continuous but with different radii of curvature so that their surfaces form a cusp at their intersection. This design allows them to be fabricated from a single casting.  more>